Avon NC - Environmental Assessment

ENVIRONMENTAL ASSESSMENT
Avon Village Beach Nourishment
Dare County, North Carolina
US Army Corps of Engineers®
Wilmington District — Washington Regulatory Field Office
2407 W Fifth Street, Washington NC 27889
JULY 2021
For more information and comments, contact Mr. Josh Pelletier, US Army Corps of Engineers,
Washington Regulatory Field Office, 2407 W Fifth Street, Washington, North Carolina , 27889
(phone [phone], facsimile 252–975–1399).

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JULY 2021 Environmental Assessment
USACE–Wilmington District (NC) i Avon Village, Dare County (NC)
TABLE OF CONTENTS
TABLE OF CONTENTS ................................................................................................................................................. i
ACRONYMS .............................................................................................................................................................. v
1.0 INTRODUCTION AND PURPOSE .......................................................................................................................... 1
1.1 Applicant ........................................................................................................................................................................... 1
1.2 Activity Location ............................................................................................................................................................... 1
1.3 Description of Activity Requiring Permit ........................................................................................................................... 1
1.3.1 Proposed Avoidance and Minimization Measures ................................................................................................. 11
1.3.2 Proposed Compensatory Mitigation ...................................................................................................................... 13
1.4 Project Background and History ..................................................................................................................................... 13
1.4.1 Project Background ............................................................................................................................................... 13
1.4.2 Project Planning History ........................................................................................................................................ 17
1.5 Permit Authority .............................................................................................................................................................. 21
2.0 SCOPE OF REVIEW FOR NATIONAL ENVIRONMENTAL POLI CY ACT (NEPA) .............................................................. 27
2.1 Determination of Scope of Analysis for National Environmental Policy Act (NEPA) ....................................................... 27
2.2 Determination of the “Project Area” for Section 7 of the Endangered Species Act (ESA) ............................................... 29
2.3 Determination of Permit Area for Section 106 of the National Historic Preservation Act (NHPA) .................................. 31
3.0 PURPOSE AND NEED ....................................................................................................................................... 33
3.1 Purpose and Need for the Project ................................................................................................................................... 33
3.2 Historical Erosion Rates and Present Beach Conditions ................................................................................................. 33
3.2.1 Methodology .......................................................................................................................................................... 34
3.2.2 Official Shoreline Change Rates ............................................................................................................................. 37
3.2.3 Recent Variations in Shoreline Change Rates ........................................................................................................ 42
3.2.4 Rhythmic Shoreline Changes ................................................................................................................................. 48
3.2.5 Beach Profile Surveys ............................................................................................................................................ 51
3.2.6 Profile Volume Analyses of July 2020 Beach Conditions ........................................................................................ 55
3.3 Basic Project Purpose ..................................................................................................................................................... 58
3.4 Water Dependency Determination ................................................................................................................................. 58
3.5 Overall Project Purpose .................................................................................................................................................. 58
4.0 CONSULTATION AND COORDINATION ............................................................................................................... 61
4.1 Results of Coordinating on Public Notice ....................................................................................................................... 61
4.2 Additional Issues Raised by t he USACE ........................................................................................................................... 64
4.3 Comments Raised That Do Not Require Further Discussion ........................................................................................... 64
5.0 ALTERNATIVES ANALYSIS ................................................................................................................................ 65
5.1 Site Selection and Screening Criteria ............................................................................................................................. 65
5.1.1 Geologic Processes ................................................................................................................................................ 66
5.1.2 Shoreli ne and Barrier Island Geomorphology ....................................................................................................... 66
5.1.3 Beach Nourishment Implementation Options ....................................................................................................... 68
5.2 Description of Alternatives ............................................................................................................................................. 71
5.2.1 ALTERNATIVE 1–NO-ACTION ................................................................................................................................. 71
5.2.2 ALTERNATIVE 2–BEACH NOURISHMENT WITH WINTER CONSTRUCTION ............................................................. 72
5.2.3 PREFERRED ALTERNATIVE 3 – SUMMER CONSTRUCTION ..................................................................................... 75
5.3 ALTERNATIVES ELIMINATED FROM FURTHER STUDY ..................................................................................................... 78
5.3.1 Rationale for Dismissing Nourishment Using Non -Offshore Sand Sources .......................................................... 78
5.3.2 Rationale for Dismissing Sand -Retaining Structures and Techniques .................................................................. 82
5.3.3 Rationale for Dismissing Other Potential Alternatives .......................................................................................... 84
5.3.4 Nourishment Construction Alternatives Eliminated from Consideration ............................................................. 85
5.4 Least Environmentally Damaging Practicable Alternative ............................................................................................. 89
6.0 EVALUATION FOR COMPLIANCE WITH SECTION 404(b) ........................................................................................ 91
6.1 Practicable Alternative ................................................................................................................................................... 91
6.2 Candidate Disposal Site .................................................................................................................................................. 91
6.3 Potential Impacts on Physical and Chemical Characteristics of Non -Living Environment ............................................. 91

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6.4 Potential Impacts on Living Communities or Human Uses ............................................................................................. 93
6.4.1 Potential Impacts on Biological Characteristics of Aquatic Ecosystem (Subpart D) ............................................. 93
6.4.2 Threatened and Endangered Species .................................................................................................................. 128
6.4.3 General Methodology of Effects Determinations .................................................................................................. 130
6.4.4 EFH Species or Complexes Considered ................................................................................................................ 156
6.4.5 Potential E FH or HAPC and Fish Species with Potential Effects .......................................................................... 165
6.5 Potential Impacts on Special Aquatic Sites (Subpart E) ...................................................................................................... 180
6.6 Potential Impacts on Human-Use Characteristics (Subpart F) ...................................................................................... 181
6.7 Pre-Testing Evaluation (Subpart G) ............................................................................................................................... 182
6.8 Evaluation and Testing (Subpart G) ............................................................................................................................... 182
6.9 Actions to Minimize Adverse Impacts ............................................................................................................................ 182
6.10 Factual Determinations (Subpart B) .............................................................................................................................. 183
6.11 Findings of Compliance/Non -Compliance .................................................................................................................... 184
7.0 GENERAL PUBLIC INTEREST REVIEW (33 CFR 320.4 and RGL 84 -09) ..................................................................... 185
7.1 Public Interest Factors .................................................................................................................................................. 185
7.2. Other Public Interest Factors ........................................................................................................................................ 189
7.2.1 Geologic and Mineral Resourc es ........................................................................................................................... 189
7.2.2 Soils and Upland Topography .............................................................................................................................. 189
7.2.3 Wetlands ............................................................................................................................................................... 189
7.2.4 Energy Resources ................................................................................................................................................. 191
7.2.5 Visual Resources ................................................................................................................................................... 191
7.2.6 Climate Change .................................................................................................................................................... 191
7.2.7 Soundscapes ........................................................................................................................................................ 192
7.2.8 Noise ..................................................................................................................................................................... 193
7.2.9 Lightscapes ........................................................................................................................................................... 193
7.2.10 Infrastructure ...................................................................................................................................................... 194
7.3 Public and Private Need ............................................................................................................................................... 194
7.4 Unresolved Conflicts as to Resource Use ...................................................................................................................... 194
7.5 Extent/Permanence of Beneficial and/or Detrimental Effects ...................................................................................... 194
8.0 CONSIDERATION OF CUMULATIVE IMPACTS ...................................................................................................... 195
8.1 Geographic Scope for Cumulative Effects Assessment ................................................................................................. 195
8.2 Identify/Describe the Direct and Indirect Effects .......................................................................................................... 195
8.2.1 Potential Effects on Species of Concern (MBTA, MMPA, State -Protected) ............................................................ 196
8.2.2 Potential Effects on Threatened and Endangered Species (see Section 6.4.3)..................................................... 197
8.2.3 Potential Effects on EFH, HAPC, or Life Stages of Associated Managed Fish ........................................................ 198
8.3 Temporal Scope of Assessment .................................................................................................................................... 208
8.4 Describe the Affected Environment .............................................................................................................................. 209
8.5 Determine Environmental Consequences .................................................................................................................... 210
8.6 Mitigation to Avoid, Minimize or Compensate for Cumulative Effects .......................................................................... 210
8.7 Conclusions Regarding Cumulative Impacts ................................................................................................................ 211
8.7.1 Potential Cumulative Effects of the Proposed Project on Species of Concern ..................................................... 211
8.7.2 Endangered and Threatened Species (ESA -Protected) ........................................................................................ 213
8.7.3 Potential Cumulative Effects of Proposed Project on EFH and HAPC ................................................................... 214
9.0 CONSERVATION AND MITIGATION MEASURES ................................................................................................... 217
9.1 Avoidance and Minimization ......................................................................................................................................... 217
9.2 Compensatory Mitigation ............................................................................................................................................. 217
10.0 COMPLIANCE WITH OTHER LAWS, POLICIES, AND REQUIREMENTS .................................................................... 219
10.1 Section 7(a)(2) of the Endangered Species Act (ESA).................................................................................................... 219
10.1.1 Other Agency Documented Compliance ............................................................................................................ 219
10.1.2 Consultation with NMFS and/or USFWS ............................................................................................................. 219
10.1.3 Effects Determination for ESA -Protected Species.............................................................................................. 225
10.2 Magnuson-Stevens Fishery Conservation and Management Act, Essential Fish Habitat ............................................. 227
10.2.1 Other Agency Document Compliance ................................................................................................................ 227
10.2.2 Review Required Under Magnuson -Stevens Act ................................................................................................ 227
10.2.3 Effect Determination .......................................................................................................................................... 227

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10.2.4 Consultation with NMFS ..................................................................................................................................... 228
10.3 Section 106 of the National Historic Preservation Act (NHPA) ..................................................................................... 228
10.3.1 Known Cultural Sites Present ............................................................................................................................ 228
10.3.2 Effect Determination on Cultural Resources ...................................................................................................... 229
10.4 Tribal Trust Responsibilities ....................................................................................................................................... 229
10.5 Section 401 of the Clean Water Act – Water Quality Certification (WQC) .................................................................... 230
10.6 Coastal Zone Management Act (CZMA) ....................................................................................................................... 230
10.7 Wild and Scenic Rivers Act —National Wild & Scenic River System ............................................................................. 230
10.8 Effects on Federal Projects —Section 14 of Rivers & Harbors Act (33 USC 408) ........................................................... 231
10.9 Corps Wetlands Policy (33 CFR 320.4(b)—Wetlands Impacts ...................................................................................... 231
11.0 SPECIAL CONDITIONS ................................................................................................................................... 233
11.1 Conditions Required ................................................................................................................................................... 233
11.2 Required Special Condition(s) .................................................................................................................................... 233
12.0 FINDINGS AND DETERMINATIONS .................................................................................................................. 235
12.1 Section 176 (c) of the Clean Air Act General Co nformity Rule Review .......................................................................... 235
12.2 Presidential Executive Orders (EO) ............................................................................................................................... 235
12.2.1 Consultation with Indian Tribes, Alaska Natives, and Native Hawaiians (EO 13175) ......................................... 235
12.2.2 Floodplain Management (EO 11988) .................................................................................................................. 235
12.2.3 Environmental Justice (EO 12898) ..................................................................................................................... 237
12.2.4 Invasive Species (EO 13112) ............................................................................................................................... 237
12.2.5 Energy Supply (EO 13212) and Availability (EO 13302) ...................................................................................... 237
12.3 Findings of No Significant Impact ............................................................................................................................... 238
12.4 Compliance with the Section 404(b)(1) Guidelines ..................................................................................................... 238
12.5 Public Interest Determination .................................................................................................................................... 238
SIGNATURES......................................................................................................................................................... 239
REFERENCES CITED ............................................................................................................................................... 240

APPENDICES A) Geotechnical Data Analyses (CSE 2021)
B) Monitoring and Mitigation Plan (CSE 2021)
C) Large Sediment Sampling Report (CSE 2021)
D) Littoral Processes (CSE 2021)
E) Biological Assessment (CZR –CSE 2021)
F) Essential Fish Habitat Assessment (CZR–CSE 2021)
G) Cultural Resources Survey (TAR 2021)

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ACRONYMS
AEC Area of Environmental Concern
ASCE American Society of Civil Engineers
BA Biological Assessment
BAV Beach Action Value
BC Berm crest
BEACH Beaches Environmental Assessment and Coastal Health (BEACH) Act of 2000
BO Biological Opinion
CAMA Coastal Area Management Act
CBIA Coastal Barrier Improvement Act
CBRA Coastal Barrier Resources Act
CEQ Council on Environmental Quality
CERC Coastal Engineerin g Research Center
CFR Code of Federal Regulations
CHWA Cape Hatteras Water Association
CSE Coastal Science & Engineering Inc
CWA Clean Water Act
CZM Coastal Zone Management
CZMA Coastal Zone Management Act
CZR CZR Incorporated
DPS Designated Population Seg ment
EA Environmental Assessment
EFH Essential Fish Habitat
EIS Environmental Impact Statement
EO Executive Order
EPA Environmental Protection Agency
ESA Endangered Species Act
FEIS Final Environmental Impact Statement
FEMA Federal Emergency Management Age ncy
GENESIS Generalized model for simulating shoreline change
GIBA Globally Important Bird Area
HAPC Habitat Areas of Particular Concern
IPCC Intergovernmental Panel on Climate Change
IUCN International Union for Conservation of Nature
LEDPA Least Environmentally Damaging Practicable Alternative
MAFMC Mid-Atlantic Fisheries Management Council
MBTA Migratory Bird Treaty Act
MMMA Marine Mammal Protection Act
MLW Mean low water
MTL Mean tide level
NAS National Academy of Sciences
NAVD North American Vertical Datum
NC 12 North Carolina State Highway 12
NCCRC North Carolina Coastal Resources Commission
NCDCCPS North Carolina Department of Crime Control and Public Safety
NCDCM North Carolina Division of Coastal Management
NCDENR North Carolina Department of Enviro nment and Natural Resources (now named NCDEQ)

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NCDEQ North Carolina Department of Environmental Quality , effective 09/21/2015 (formerly NCDENR)
NCDMF North Carolina Division of Marine Fisheries
NCDOT North Carolina Department of Transportation
NCDNCR North Carolina Department of Natural and Cultural Resources
NCSG North Carolina Sea Grant
NCDWR North Carolina Division of Water Resources
NCNHP North Carolina Natural Heritage Program
NCWRC North Carolina Wildlife Resources Commission
NDBC National Data Wave Buoy
NEPA National Environmental Policy Act
NFIP National Flood Insurance Program
NHPA National Historic Preservation Act
NMFS National Marine Fisheries Service
NMNH National Museum of Natural History
NOAA National Oceanic & Atmospheric Administration
NOI Notice of Intent
NOS National Ocean Service
NPS National Park Service
NRC National Research Council
NRCS Natural Resources Conservation Service
OCRM Office of Ocean & Coastal Resource Management
OPA Otherwise Protected Area
OSHA Occupational Safety and Heal th Administration
PEPC Planning, Environmental and Public Comment
PRD Protected Resource Division [National Marine Fisheries Service (NOAA)]
SAFMC South Atlantic Fisheries Management Council
SARBO South Atlantic Regional Biological Opinion
Seashore Cape Hatteras National Seashore
SERO Southeast Regional Office (NOAA)
SHPO North Carolina State Historic Preservation Office
SOSUS Sound Surveillance System
STWAVE Steady-state spectral wave model
USACE US Army Corps of Engineers
USDA US Department of Agriculture
USFWS US Fish & Wildlife Service
USGS US Geological Survey
WIS Wave Information Study

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USACE–Wilmington District (NC) 1 Avon Village, Dare County (NC)
1.0 INTRODUCTION AND PURPOSE
1.1 Applicant
The applicant of the proposed beach restoration project is Dare County. It is a municipal corporation
located in North Carolina. The applicant’s contact information is as follows.
County Manager: Mr. Robert Outten
Address: 954 Marshall Collins Drive, Manteo, NC 27954
Telephone: [phone] Fax: [phone] Website: www.darenc.gov
1.2 Activity Location
The Avon project area is located on Hatteras Island along the Cape Hatteras National Seashore (Seas hore),
in front of the Village of Avon, approximately 4 miles north of Buxton , in the Outer Banks of North Carolina.
Hatteras Island is part of a nearly continuous chain of barrier islands which extend from New York to
Florida. As shown in Figure 1.1, the Seashore includes portions of the islands of, Hatteras, Bodie, and
Ocracoke, which together offer about 70 mile s of ocean shoreline. A similar length chain of barrier islands
immediately to the south comprise the Cape Lookout National Seashore.
The project area faces east, and encompasses ~2.5 miles (out of ~3.4 miles) of Avon Village oceanfront.
The project begins ~4,000 feet (ft) north of the Avon Pier and extends south to the village border with the
Cape Hatteras National Seashore as shown in Figure 1.2. The northern project boundary is located at
35°21'27.20'' N 75°29'54.52'' W (35.3575 N 75.4985 W), and the southern boundary at 35°19'19.22'' N
75°30 '26.27'' W (35.3220 N 75.5073 W).
Pamlico Sound borders the project area on the west, and the Atlantic Ocean bounds the project area on
the east. Oregon Inlet, the closest inlet to the project area , is located ~30 miles north of the project area.
The offshore borrow areas where the sand will be excavated are located within the 3-nautical-mile limit
and therefore do not fall within federal waters as shown in Figure 1.2.
1.3 Description of Activity Requiring Perm it
Dare County (NC) is proposing a beach restoration project, which calls for up to 1.0 million cubic yards
(cy) of beach quality sand to be pumped onto the 2.5-mile (13,200 linear feet) beach via offshore
dredging scheduled to start the summer of 20 22 . The anticipated average fill density (volume of
nourishment per linear foot of beach) is ~76 cubic yards per linear foot (cy/lf) of shoreline. This is
equivalent to an average beach width increase after a natural profile adjustment of ~60 feet (ft). The fill
density will be varied by reach according to the site’s specific deficit volume and erosion rate with an
average range of ~43 –90 cubic yards per foot (cy/ft). The purpose of the project is to restore sand losses
caused by long-term erosion as well as accelerated recent erosion (CSE 2020). Some of the volume will
provide advance nourishment along the most critically eroded area south of Avon Pier.

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USACE–Wilmington District (NC) 2 Avon Village, Dare County (NC)
The proposed beach nourishment project would be implemented using the same construction method (ie
– offshore dredging) and would be completed within the same construction window (ie – during summer
months) as other recent projects at Rodanthe (USACE 2013) and Buxt on (CSE 2018). The 2.5 miles of beach
that would be filled by the proposed project is calculated to create ~3.5 acres of new dune habitat and ~15
acres of new dry beach habitat . Figure 1.3 shows typical fill sections for the two project reaches illustrat ed
in Figure 1.2. A dune would be incorporated along areas south of the Avon Pier lacking a healthy foredune
or where the existing dune requires enhancement to increase storm protection and resiliency.
The proposed offshore borrow area (Figu res 1.2 and 1.4) is 250 acres, located 2–3 miles east northeast of
Avon Pier within state waters. It consists of two adjacent areas within which 12 cores were obtained to
confirm sediment quality. A rea 1, representing about 55 percent of the borro w area, is proposed for
excavation to 10 ft below the substrate. The remainder, Area 2, is proposed for 6 ft excavations. Combined,
the two areas, if dredged to the maximum depth, would provide up to 3.4 million cubic yards of beach-
quality sand.
Mean grain size in the Avon littoral profile (foredune to –24 ft NAVD) in 2020 was 0.289 millimeters (mm)
with 4 percent shell content, 1.7 percent granules (2 –4 mm), and 0.1 percent gravel (4 –76 mm). The
subaerial mean grain size (more representative of the recreational beach) was 0.323 mm in 2020. The
borrow area (Figure 1.4) has a composite mean grain size of 0.308 mm with 16.4 percent shell material, 2.6
percent granules, and 0.2 percent gravel to a depth of 10 ft in Area 1 (Figure 1.5). Area 2 has a composite
mean grain size of 0.331 mm with 16.8 percent shell material , 5.1 percent granules, and 0.7 percent gravel
by weight. The sediment quality and core density (~1 per 20 acres) meet NC state stan dards for beach
nourishment sediment quality.
The proposed borrow area is part of an isolated underwater ridge that will be excavated mainly over the
crest and inshore flank leaving undisturbed areas and topography while avoiding the creation of deep
holes during the dredging operation. Figures 1.6 and 1.7 show an example core photo log and stratigraphy
log. See Appendix A for detailed geotechnical data and analysis for the beach and borrow area sediments.
A submerged cultural resource remote -sensing survey of the proposed borrow area was conducted by
Tidewater Atlantic Research (TAR) of Washington, North Carolina. Field work was completed by 24 July
2021, and the results and findings are included in Appendix G - Cultural Resources Survey of this
Environmental Assessment. Work performed by TAR consisted of a background literature survey,
historical research, and cartographical investigation. Field investigations identified three magnetic
anomalies inside the proposed borrow area, and three within the 200 -ft perimeter of the borrow area.
All six anomalies represent very small ferrous objects. None appear to represent a potentially
significant submerged cultural resource and therefore, no avoidance was recommended . Analysis of
the acoustic data identifie d no evidence of sonar targets in the borrow area or its immediate vicinity.
Consequently, no potentially significant submerged cultural resources will be impacted by dredging in
the proposed borrow area or its adjacent 200 -ft buffer.

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FIGURE 1.1. Location of Avon and Cape Hatteras National Seashore, Dare County, North Carolina.

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USACE–Wilmington District (NC) 4 Avon Village, Dare County (NC)
FIGURE 1.2. The project area for the proposed beach nourishment project at Avon Village, Dare County (NC), showing
maximum limit of beach nourishment and proposed offshore borrow area within state waters near Avon. Reaches 1 and 2
(not shown) are No Work areas north of the project. Reach 5 (not shown) is a No Work area south of the proposed project
for purposes of downcoast monitoring along the undeveloped Cape Hatteras National Seashore. Reaches and stationing
after CSE (2020).

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USACE–Wilmington District (NC) 5 Avon Village, Dare County (NC)
FIGURE 1.3. Representative fill templates at station 1560+00 for Reach 3 (north of Avon Pier) and 1610+00 for Reach 4.
Beach profiles represent the beach condition in July 2020. An initial dune is proposed to be constructed along portions of
Reach 4. The dune crest is set to be at +13 ft NAVD and the seaward slope is 1 on 3. The typical dune crest widt h is 20 ft,
and the constructed dry -sand berm in front of the dune is approximately 164 ft at station 1610+00 (~2,000 ft south of Avon
Pier).

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USACE–Wilmington District (NC) 6 Avon Village, Dare County (NC)
FIGURE 1.4. Mean grain size, percent shell, and percent gravel for core composite samples to 10 ft in the pr oposed offshore Borrow
Area 1 and 6 ft in the proposed Borrow Area 2 based on borings obtained in April 2021. Each boring has a uniform length of 1 0 ft.
Composite results of the twelve vibracores are listed in the inset table on the upper left.

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FIGURE 1.5. Sediment grain size distributions (GSDs) for Avon native beach samples (n=70) compared with offshore
samples in the proposed borrow area (composite). [UPPER] Borrow Area 1 where 10 ft excavation depth is proposed.
[LOWER] Borrow Area 2 where 6 ft excavation depth is proposed. In both borrow areas, sediments are expected to be
slightly coarser than the native beach initially. Over time, the grain size of the post -nourishment beach is expected to
move closer to the historical grain size distribution around Avon.

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FIGURE 1.6. Example core photo log for one of the 10 -ft borings (AV-27) obtained by subconsultant American Vibracore
Services (AVS) in April 2021.

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USACE–Wilmington District (NC) 9 Avon Village, Dare County (NC)
FIGURE 1.7. Core log for AV-27 showing the lithology, sample intervals, and mean grain si zes.

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USACE–Wilmington District (NC) 10 Avon Village, Dare County (NC)
The proposed project goals are to:
 Replace sand losses due to chronic long-term erosion and accelerated erosion during
the past decade.
 Provide a wider beach and buffer storm waves along a critically eroding section of
Hatteras Island.
 Protect North Carolina Highway 12 (NC 12) and reduce the frequency of flooding,
road closures , and storm damages.
 Provide a wider recreational beach and create more habitat for wildlife.
 Provide enhanced dune protection where there is little or no protective dune.
Completion of the proposed project will serve as an important step toward the County’s implementation
of a long-term plan for beach management and storm damage reduction along vulnerable areas of
Hatteras Island. Further, the proposed project addresses erosion along one of the likely sediment
management activities areas identified in the recent Programmatic EIS of the Sediment Management
Framework by the National Park Service for Hatteras Island (NPS 2021a).
This Environmental Assessment (EA) includes the following:
1) Description of activity requiring a permit (Section 1)
2) Scope of review for the National Environmental Policy Act (NEPA) (Section 2)
3) Purpose and need for the project (Section 3)
4) Consultation and coordination with federal, state, local entities (Section 4)
5) Alternatives analysis (Section 5)
6) Evaluation and compliance with Section 404(b) (Section 6)
7) General Public Interest Review 33CFR 320.4 and RGL 84 -09 (Section 7)
8) Consideration of cumulative impacts (Section 8)
9) Conservation and mitigation measures (Section 9)
10) Compliance with other laws, policies, and requirements (Section 10)
11) Special conditions (Section 11)
12) Findings and determinations (Section 12)
13) References cited
Supplementary data and analyses pertinent to the proposed project are contained in Appendices A−G.
Appendix A) Geotechnical Data Analyses — Contains geotechnical d ata on the proposed borrow area
and the native Avon and National Seashore beach, and presents detailed results of beach sampling and
borrow-area coring.

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Appendix B) Monitoring and Mitiga tion Plan — Based on similar special conditions prescribed for beach
nourishment during summer months in North Carolina at Nags Head, Rodanthe, Kill Devil Hills, Duck, Kitty
Hawk, and Buxton. Describes the anticipated monitoring and protect ion measures for the proposed
nourishment at Avon.
Appendix C) Large Sediment Sampling Report — Provides results of field data collection along the
project beach Spring 2021 per state requirements under CRC Rules 15A NCAC 07H.0312 (new rule).
Appendix D) Littoral Processes — Provides detailed discussion and additional data analyses of erosion,
wave climate, and littoral processes in the Avon project area and the predicte d performance of the
proposed nourishment project.
Appendix E) Biological Assessment (BA) — Analyzes the potential effects of the proposed nourishment
on federally listed threatened, endangered, candidate animal species (wildlife, invertebrates, and fish) or
plant species, and designated or proposed critical habitats pursuant to Section 7 of the Endangered
Species Act of 1973 (as amended). It is similar to a report for the nearby Buxton renourishment project
and builds on the original BA for the Buxton 2017–2018 nourishment project (CSE 2015 a).
Appendix F) Essential Fish Habitat Assessment (EFH) — Evaluates the impact of the proposed
nourishment to essential fish habitat or habitat areas of particular concern for those species managed by
the South Atlantic Fisheries Management Council (SAFMC) and Mid -Atlantic Fisheries Management Council
(MAFMC). It is similar to a report for the nearby Buxton renourishment project (CZR -CSE 2021).
Appendix G) Cultural Resources Survey — Provides the methodology and results of a submerged cultural
resource, remote-sensing survey of the proposed borrow areas , and identifies any magnetic anomalies in
those areas.
1.3.1 Proposed Avoidance and Minimization Measures
To prevent and minimize potential adverse impacts associated with the proposed project, certain
management and avoidance/minimization measures would be implemented d uring construction. Upon
project completion, the project area would be left to adjust naturally and no further maintenance or
manipulation of the beach would be involved. Additional monitoring activities before, during, and after
construction are anticip ated in conformance with the Biological Opinion (BO) for the project (to be issued
at a later date). The applicant anticipate s that state and federal permits required before this proposed
project proceeds with construction would include a variety of condi tions specifically related to the
protection of water quality and natural resources from construction -related impacts. If the USACE and
NPS decide to permit the proposed project, then the following avoidance and minimization measures
would be incorporated into the terms and conditions of the USACE federal permit and the NPS Special Use
Permit.

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1.3.1.1 Coastal Resources and Soils/Wetland Resources/Wildlife and Wildlife Habitats
 A pre-construction environmental meeting would be convened with the state and federal resource
and regulatory agencies, the USACE, the NPS, the NCDEQ, the contractor, and the engineer to
review protocols and environmental protection measures mandated under the permits.
 Equipment mobilization and use would be via designated beach ac cesses and along the con-
structed berm so as to avoid impacts to vegetated areas.
 Pipe and material along the beach would be moved under escort by qualified biologists so as to
avoid any nesting activity or sensitive habitat designated by the state and federal resource
agencies.
 Appropriate measures would be employed to prevent or control spills of fuels, lubricants , or other
contaminants from entering waterways or sensitive areas. Actions would be consistent with state
water quality standards and the Cle an Water Act Section 401 certificate requirements. A
hazardous spill plan would be approved by the USACE and NPS and appropriate resource agencies
prior to construc tion. This plan would state what actions would be taken in the case of a spill,
notification measures and prevention measures to be implemented, such as the placement of
refueling facilities, storage, and handling of hazardous materials.
 Equipment on the beach would be moved to a safe location within the vicinity of the project area
upon a weather forecast of high wave and water conditions.
 The contractor would not leave vehicles idling for excessive periods when parked or not in use.
 Sea turtle nests la id immediately prior to or during construction within the project area would be
relocated by trained observe rs under the guidance of the NPS, US Fish and Wildlife Service
(USFWS), and NC Wildlife Resources Commission (NCWRC) officials.
 Wildlife collisions would be reported to federal and state resource personnel.
 Injury or death of wildlife would be reported to USACE and NPS personnel and other applicable
agencies, such as the USFWS and NCWRC.
1.3.1.2 Vegetation
 No construction activities or equipment storage would occur in vegetated areas.
 Post-project dune planting or sand fencing are in cluded in the project plans. Such activities would
only occur along the most critically eroded oceanfront of the Village of Avon, be performed soon
after completion of dredging operations , and would be accomplished under the supervision of
qualified individuals to insure compliance with the project design, terms, and special conditions
of the state and federal permits.

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USACE–Wilmington District (NC) 13 Avon Village, Dare County (NC)
1.3.1.3 Threatened and Endangered/Special Status Species
 The applicant would coordinate with the resource agencies (NPS, USFWS, NCWRC) regarding the
need to restrict construction in the vicinity of active nest building by sea turtles, shorebirds, or
nesting water birds if any. (For a more detailed discussion regarding mitigation procedures to
protect these species, see Sections 6, 8, and 10.)
 The applicant would coordinate during dredging operations with the NPS and National Marine
Fisheries Service (NMFS) regarding specific restrictions, operations procedures, and protection of
turtles, Atlantic sturgeon, whales, and other marine mammals.
 The applicant would comply with no-work buffers established by the resource agencies around
active nests or other designated habitat requiring protection if any.
1.3.1.4 Cultural Resources
 Construction would be stopped if cultural resources are encounte red, and the contractor would
coordinate protective measures to minimize disturbance with North Carolina’s State Historic
Preservation Office (SHPO).
 Potential cultural resources detected i n the offshore borrow area (Appendix G–Cultural Resources)
would be avoided during dredging operations by establishing no -work buffers around the objects.
1.3.2 Proposed Compensatory Mitigation
Because the proposed project is water-dependent (can only occur in proximity to an aquatic environment)
and there is likely to be no change or only an incremental increase in wetland habitat, the proposed project
does not need to prepare plans for compensatory mitigation that restores wetlands.
The following best-management practices would be observed:
 Nourished shoreline would have similar slopes and elevations as the existing shoreline.
 Use of heavy equipment to shape the pumped sand would leave no trace of disturbance when
restoration efforts are complete.
1.4 Project Background and History
1.4.1 Project Background
The Village of Avon is one of seven historic villages on Hatteras Island situated adjacent to (and within) the
Cape Hatteras National Seashore (CAHA) between Salvo and Buxton around mile marker 36. It is an
unincorporated community under the jurisdiction of Dar e County with a 2010 population of 776
permanent residents. South of the Tri -Villages of Rodanthe, Waves , and Salvo, past a ~11.5-mile stretch of
the undeveloped Cape Hatteras National Seashore, Avon is considered the largest and busiest of the
Hatteras I sland towns. There are another ~20,000 feet (~3.8 miles) of the Cape Hatteras National Seashore
between the south boundary of Avon and Buxton, the next village along the barrier island (see Figure 1.1).

JULY 2021 Environmental Assessment
USACE–Wilmington District (NC) 14 Avon Village, Dare County (NC)
Avon is bordered to the east by the Atlantic Ocean a nd to the west by Pamlico Sound , with a total land
area of ~2.4 square miles, as shown in the location map . Avon’s primary industry is tourism, with hundreds
of homes and dozens of motels and campgrounds available for short -term rentals. There are also f acilities
on the ocean and sound side to accommodate the recreational fishing community, surfers, and boaters.
NC Highway 12 is the main artery for public and emergency vehicle access to the Avon and Hatteras Island
communities and National Seashore facil ities.
Avon Ocean Pier is located close to the center of the village and provides a useful landmark on maps. The
section of shoreline north of the pier has generally been relatively stable over the past 50 years (NCDENR
2012). In contrast, the southern ~1 .5 miles of Avon (south of the Avon Pier) has experienced accelerated
erosion in recent years (Figure 1.8). The dunes along this highly eroding section of the beach have been
washed away, and ocean waves have frequently washed over and flooded NC Highway 12 during inclement
weather events (Figure 1.9). This occurs not only in named storms but also in common nor’easters and
during fairweather extreme tides (Figure 1.10). The County reported that “the overwash [on NC Hwy 12] has
impeded, and at times prevented, first responders from responding to emergencies; our sanitation workers from picking
up trash; the citizens of Avon from performing normal daily tasks, such as attending doctor appointments, buying
groceries, attending community events, and the list goes on. In addition to the safety issues, there has been flood
damage to homes and businesses, and it has negatively affected our tourism economy.” (Source: Dare County’s More
Beach to Love at https://www.darenc.com/government/avon -beach-nourishment/avon-faq).
In response to the emergent need for beach restoration in Avon Village, Dare County completed a
feasibility study to assess erosion and formulate solutions along the Village of Avon in November 2020 (CSE
2020). T his feasibility report evaluates the beach in detail upcoast and downcoast of the critically eroded
area to place the area in context and establish linkages with the sand sharing system alongshore . It also
provided several levels of beach restoration plans for different project longevities.
The selected plan was determined by Dare County officials based on the funds available with a goal of
providing up to five years of erosion relief upon restoration of the sand deficit identified in the feasibility
report. Details of the erosion analysis and beach conditions are given in Section 3.0 and Appendix D
(Littoral Processes). The proposed plan was informed by the past and recent nourishment projects along
Buxton Village (Dolan 1972; USACE -DOI-NPS 2015) and the National Seashore south of the Ha ulover Day
Use Facility, as well as numerous academic studies and agency technical reports as detailed in the next
section.

JULY 2021 Environmental Assessment
USACE–Wilmington District (NC) 15 Avon Village, Dare County (NC)
FIGURE 1.8. Aerial photo taken on 15 July 2020 showing the highly eroded section of Avon (Reach 4). The ground
photo was taken by Daniel Pullen on 20 September during Hurricane Teddy. NC Highway 12 was closed for 5
consecutive days due to overwas h caused by ocean swell generated by Teddy, despite the fact that the
hurricane’s track kept it hundreds of miles east of Bermuda as well as offshore of the Outer Banks.
FIGURE 1.9. Ground photo taken by Daniel Pullen in front of Supermarket Food Lion on 20 September 2020. It
shows the extensive flooding and un-accessible road condition of NC Highway 12 at Avon.

JULY 2021 Environmental Assessment
USACE–Wilmington District (NC) 16 Avon Village, Dare County (NC)
FIGURE 1.10. [UPPER] Fairweather flooding and washovers at high tide along the Avon oceanfront south of
the pier on 11–12 October 2019. [LOWER] High tide flooding along Highway NC 12 on 11 –12 October 2019 in
Avon Village. (Photos courtesy of Epic Shutter Photography)

JULY 2021 Environmental Assessment
USACE–Wilmington District (NC) 17 Avon Village, Dare County (NC)
1.4.2 Project Planning History
In preparing this EA, the applicant referen ced extensive literature r elated to Avon, Buxton, National
Seashore, and environs. The applicant also used the literature review conducted for the Environmental
Assessment: Beach Restoration to Protect NC Highway 12, at Buxton, Dare County, North Carolina (USACE–
DOI –NPS 2015), Final Environmental Impact Statement: Beach Nourishment Project, Town of Nags Head,
North Carolina (USACE 2010), and Environmental Assessment: Nags Head Beach Renourishment, Town of
Nags Head, North Carolin a (USACE 2017). After completion of an EA for the initial Buxton nourishment
project (USACE-DOI-NPS 2015), the NC Department of Transportation completed a Feasibility Study of
potential transportation improvements to NC 12 from Avon to Buxton (NCDOT 201 5). That report
projected that erosion was likely to compromise the highway in the short -term (5 years) as well as the
long-term (50 years).
Recently, NPS completed a Programmatic EIS for beach nourishment and sand management along the
Cape Hatteras National Seashore (NPS 2021 a) which lists Avon as one of the erosion hot spots along
Hatteras Island likely to require beach restoration over the next 20 years. The present review included
articles, reports, environmental impact statements, and environmental assessments on similar pr ojects
along the Outer Banks pub lished between 1943 and 2017. Table 1.1 lists some of the key plans and studies
which informed the development of alternatives for the proposed project. Additional background
information and references are contained in Ap pendices A –G of this EA.
The proposed beach restoration project was initiated by the Dare County Board of Commissioners
following strong local support from the community, particularly in light of recent erosion of the foredune.
No previous nourishment has been performed along Avon. However, several nourishment project s along
Buxton between the 1960 s and 2018 provide relevant data because of the proximity to Avon. Table 1.1
lists selected plans and studies which were utilized in the preparation of the pla n for this area.

TABLE 1.1. Annotated list of plans and studies which informed and contributed to the development of alternatives according
to the Applicant. USACE – US Army Corps of Engineers. CRA – Coastal Research Associates (Charlottesville, V A). ECU – East
Carolina University (Greenville, NC.) CSE – Coastal Science & Engineering (Columbia, SC). CZR – CZR Incorporated
(Wilmington, NC). NCDOT – North Carolina Department of Transportation.
Date Title Source Description

1963 Report on Operation Five
High. App 6–19. Closure of
Buxton Inlet
USACE Documents impacts of March 1962 Ash Wednesday storm,
which breached Hatteras ~2 miles south of Avon Village
near the Proposed Action Area.
1974
Buxton Beach 1973
Nourishment Project: An
Annotated Photographic Atlas
CRA
Prepared for NPS, report documents the 1973 beach
nourishment project; ~1,300,000 cy pumped from Cape
Point to Buxton Action Area ~4 miles south of Avon;
constructed between April and September.

JULY 2021 Environmental Assessment
USACE–Wilmington District (NC) 18 Avon Village, Dare County (NC)
1983
Report on Shoreline
Movement: Ca pe Henry
(Virginia) to Cape Hatteras
(North Carolina), 1849–1980
USACE
Comprehensive shoreline change data spanning 130 years
includes ocean and sound shorelines. Documents erosion
of ocean shorelines averaging ~0.8 meter per year and
sound shoreline at 0.1 meter per year. Documents 30 inlets
opened and closed during the past ~400 years (ie – approx.
7.5 inlets per century) with all but three of them (Oregon,
Hatteras,) being short -lived.
2000
FEIS on Hurricane Protection
and Beach Erosion Control:
Dare County Beaches (NC)
USACE
Recommends nourishment along ~14 miles of Bodie Island
beaches including 10 miles along Nags Head. Addresses
many of the environmental impacts that need to be
considered for other nourishment projects in Dare County.
2006
Management Policies – The
Guide to Managing the
National Park System
NPS
Report outlines mandate for preserving and protecting
America’s national parks. For national seashores, the
management policies discourage interference of natural
barrier-island processes, in response to past modification of
parks by development, construction/maintenance of roads,
and rebuilding dunes.
2007
The Creation and
Establishment of Cape
Hatteras National Seashore:
The Great Depression through
Mission 66
NPS
Describes Seashore history , including early beach erosion
control and dune restoration measures in the 1930s, the
disposition of the Cape Hatteras Light Station, and efforts
to improve park access by ferry and road construction.
2008 North Carolina’s Coasts in
Crisis: A Vision for the Future ECU Presents a theory that Hatteras Island is evolving toward a
string of isolated islands separated by numerous tidal
inlets, due principally to sea level rise.
2010
FEIS: Beach Nourishment
Project, Town of Nags Head
(North Carolina)
USACE
FEIS for the 4.6 million cy beach nourishment project
completed between May and October 2011 along the Town
of Nags Head. The 10-mile-long project used an offshore
borrow source and was constructed by dredge with
environmental protection measures prescribed under the
permits. Project was locally funded and first in the northern
Outer Banks to utilize offshore borrow areas and summer
construction.
2012
NPS Beach Nourishment
Guide: Natural Resource
Technical Report
NPS/NRSS/GRD/NRTR-
2012/581
NPS
Provides guidance to better plan and manage beach
nourishment projects when beach nourishment is
determined to be consistent with NPS management
policies. Under NPS policies allowing intervention in
natural geologic processes (pg 3), the Avon Proposed
Action must satisfy requirements for sediment quality,
endangered species protection, and preservation of
natural barrier-island processes.
2013
Inventory of Coastal
Engineering Projects in the
Cape Hatteras National
Seashore
NPS
Provides information on prior coastal engin eering projects
identified in or immediately adjacent to the Seashore: 48
coastal structures, 17 beach nourishments, 5 dredging
projects, and 2 dune construction projects.

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USACE–Wilmington District (NC) 19 Avon Village, Dare County (NC)
2013
Shoreline Erosion Assessment
& Plan for Beach Restoration:
Rodanthe & Buxton Areas,
Dare County, North Carolina
CSE
Evaluates the feasibility and probable costs of beach
restoration and maintenance for up to ten years in the
Rodanthe and Buxton areas on Hatteras Island. It
established a baseline and stationing for Hatteras Island
beginning at Oregon Inlet and was the first report to
quantify sand deficits in the littoral zone to the
approximate depth of closure (DOC) for any communities
on Hatteras Island.
2014
Nags Head 2011 Beach
Nourishment Project: Post-
Year 2 and Final Report
CZR
CSE
In accordance with the benthic monitoring plan of
NCDENR/NCDCM Permit 45-10, presents results of (1) pre-
and post-nourishment biological sampling, (2) method -
logy and results from 4 seasonal pre -nourishment benthic
sampling events and 8 seasonal po st-nourishment benthic
sampling events. Compares results of species abundance
and diversity in the Action Area and adjacent unnourished
areas providing relevant guidance for biological impacts of
the proposed Avon project.
2014
Monitoring and Analysis of the
2011 Nags Head Beach
Nourishment Project
CSE
Presents beach-condition survey results covering three
years of physical monitoring following construction of the
2011 beach nourishment project. Provides break -downs of
nourishment volumes remaining within four segments of
the beach and six cross-shore zones. Data document the
longshore and cross-shore adjustment of the nourishment
and its response to storm events, including Hurricane Irene
(27 August 2011) during construction and Hurricane Sandy
(27 October 2012). The results confirmed high sand
retention within the project area during the first five years
after placement
2015 Environmental Assessment
USACE
USDOI
NPS
Environmental Assessment with detailed appendices
prepared in connection with the 2018 Buxton Beach
Restoration Project in accordance with the National
Environmental Policy Act (NEPA) of 1969. The NPS-required
format followed in close coordination with USACE
requirements. Detailed alternatives considered and the
Preferred Alternative — Nourishment with Summer
Construction for a 2.6 million cy restoration of ~15,500 lf of
NPS Seashore and Buxton Village shoreline to protect NC 12.
2015 Feasibility Study NCDOT
Feasibility of “5-year” and “50-year” transportation
improvements to NC 12 between Avon and Buxton. The
alternatives considered included beach nourishment, dune
enhancement, road realignment with, and without bridges,
and combinations of road realignment and nourishment.
2017 Environmental Assessment USACE
Environmental Assessment prepared in connection with
the 2019 Nags Head Renourishment Project – 10.0 miles at
4.0 million cy. The plan references post -Hurricane Matthew
sand replacement (under FEMA community assistance
grant) and planned renourishment by the Town of Nags
Head with Dare County (no state funding).

JULY 2021 Environmental Assessment
USACE–Wilmington District (NC) 20 Avon Village, Dare County (NC)
2019 Final Report
Nags Head Renourishment
Project
CSE
Presents a summary of the planning, permitting, and
construction of the 2019 Nags Head renourishment project
which placed 4.0 million cy along 10.0 miles of oceanfront
via hopper dredges between 1 May and 18 August 2019 with
one turtle incident onboard the hopper dredge despite all
established operational protocols and tr awling ahead of
the dredge followed. Eight (8) successful turtle nests were
laid within the project limit s during construction which
exceeds the pre-nourishment through 2010 average of ~1.8
nests per year along Nags Head. Approximately 1.4 Mcy
represented sand losses due to hurricanes and restoration
funded by FEMA under community assistance grants to
restore the beach profile.
2019 Beach Monitoring Report
Buxton-Post Dorian CSE
Summarizes volume changes and beach condition
following the 2017–2018 Buxton nourishment project and
aftermath of Hurricane Dorian. Provides insight regarding
likely storm impacts along Avon.
2019 Shorebird Monitoring and
Management at Cape Hatteras NPS
Annual report summarizing bird monitoring and protection
on Hatteras Island with particular focus on the
undeveloped section immediately downcoast of the
proposed Avon beach restoration project.
2020 FEMA Documentation
Buxton Nourishment Project CSE
Provides analysis of sand losses along the Buxton project
area due to Hurricane Florence (September 2018) and
(September 2019). Basis for FEMA beach restoration
authorization. Provides funds to help lower mobilization
costs of the proposed Avon project if Buxton can be
renourished around the same time.
2021 Programmatic EIS for Beach
Nourishment at Cape Hatteras
National Seashore
NPS
Review of past and potential future beach nourishment
activities within the National Seashore and detailed
requirements for implementation and environmental
protection. Record of Decision (ROD) issued as a
companion document in May. The Village of Avon is listed
as an erosion hot spot that will likely requir e future beach
restoration to protect Highway NC 12 and maintain public
access to the National Seashore.

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USACE–Wilmington District (NC) 21 Avon Village, Dare County (NC)
1.5 Permit Authority
Federal regulations require the USACE and NPS to involve the interested and affected public in a review
and comment process under the National Environmental Policy Act of 1969 (NEPA).
During preparation of this EA and supporting appendices, many agencies were contacted for information
as documented in each report. These included NCDEQ –Division of Coastal Mana gement (NCDCM), Division
of Marine Fisheries (NCDMF), Wildlife Resources Commission (NCWRC), and the Natural Heritage Prog ram
(NCNHP), State Historic Preservation Office (SHPO), National Oceanic and Atmospheric Administration –
National Marine Fisheries Serv ice (NOAA-NMFS), and USACE-Wilmington (Planning Section).
There are no ethnographic or Indian Trust resources in the project area, so no tribal consultations were
required.
The proposed borrow areas are located within the 3 -nautical-mile state waters limit; therefore, no consul-
tations with the Bureau of Ocean Energy Management (BOEM) were required. Table 1.2 provides federal
and state laws, regulations , and policies relevant to this EA.

JULY 2021 Environmental Assessment
USACE–Wilmington District (NC) 22 Avon Village, Dare County (NC)
Table 1.2. US laws and regulations covering the coas tal zone (presented in order of year passed)
Name Administered by Purpose
1968 National
Flood Insurance
Program (NFIP)
(Created under
the National
Flood Insurance
Act)
Federal Emergency
Management Agency
(FEMA)
 To reduce the loss of life and damage caus ed by flooding
 To help victims recover from floods
 To promote an equitable distribution of costs among those
who are protected by flood insurance and the general public
(NFIP Coastal Regulations–1968 to Present. (2011). NC Cooperating
Tech. State.
www.ncfloodmaps.com/pubdocs/fact_sheets/coastal_regs.pdf.
Accessed 22 February 2021).
1969 National
Environmental
Policy Act
(NEPA)
Council on
Environmental
Quality (CEQ)
Prescribes requirements of federal agencies for reviews of proposed
actions involving work in federal lands or where there is a federal
interest.
1972 Clean
Water Act (CWA)
Environmental
Protection Agency
(EPA)
Establishes the basic structure for regulating discharges of pollutants
into the waters of the United States and regulating quality standards
for surface waters. Enacted in 1948 as the Federal Water Pollution
Control Act, the CWA was reorganized and expanded in 1972.
1972
Coastal Zone
Management Act
(CZMA)
Office of Ocean &
Coastal Resource
Management (OCRM)
/ National Oceanic
and Atmospheric
Administration NOAA
 To manage the nation's coastal resources, including the
Great Lakes
 To balance economic development with envi ronmental
conservation
 To preserve, protect, develop, and where possible, to restore/
enhance the resources of the nation's coastal zone
The CZMA also established:
 National Coastal Zone Management Program to balance
competing land and water issues in the coastal zone, and
 National Estuarine Research Reserve System to identify field
laboratories for research to arrive at a greater understanding
of estuaries and how humans impact them
(NFIP Coastal Regulations–1968 to Present (2011). NC Cooperating
Tech. State.
www.ncfloodmaps.com/pubdocs/fact_sheets/coastal_regs.pdf .
Accessed 22 February 2021)

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USACE–Wilmington District (NC) 23 Avon Village, Dare County (NC)
1972 Marine
Mammal
Protection Act
(MMPA)
National Marine
Fisheries Service
(NMFS)/
National Oceanic and
Atmospheric
Administration
(NOAA)/ US
Commerce
Department
 To protect whales, dolphins, porpoises, seals, and sea lions by
establishing a national policy:
 To prevent marine mammal species and population stocks from
declining to the degree they are no longer a significant part of
their ecosystem.
 To manage populations to maintain the health and stability of the
marine ecosystem.
 To set requirements for animal population management that
places the benefit of the animal before commercial exploitation.
 To prohibit the taking (harassment, injury, killing) of marine
mammals unless exempted or specifically permitted or
authorized as desc ribed in Section 101(a) (5) (A) and (D).
 To require ESA Sect. 7 consultation for the issuance of incidental
take authorizations under the MMPA.
(www.nmfs.noaa.gov/pr/.; https://www.fisheries.noaa.gov/topic/laws-
policies#marine-mammal-protection-act. Accessed 22 February 2021)
1973 Endangered
Species Act (ESA)
US Fish and Wildlife
Service (USFWS) / US
Department of the
Interior / National
Marine Fisheries
Service (NMFS) / US
Commerce
Department
 To designate/ conserve species that are endangered or threatened
throughout all or a significant part of their range
 To conserve the ecosystems on which they depend
 To replace the Endangered Species Conservation Act of 1969

Endangered Species Act (ESA). No pub date. NOAA Fisheries.
https://www.fisheries.noaa.gov/topic/laws-policies#endangered -
species-act. Accessed 22 February 2021)
1982 Coastal
Barrier
Resources Act
(CBRA)
USFWS / US
Department of the
Interior
 To designate relatively undeveloped coastal barrier areas along
the Atlantic and Gulf Coast as part of the John H. Chafee CBRS
 To outline how to identif y, map, and maintain CBRS areas
 To minimize the loss of human life, wasteful expenditure of
Federal revenues, and damage to fish, wildli fe, and other natural
resources
 To restrict future federal expenditure s and financial assistance
which have the effect of encouraging development in these
sensitive areas.
(NFIP Coastal Regulations–1968 to Present. [2010] NC Cooperating
Tech. State.
www.ncfloodmaps.com/pubdocs/fact_sheets/coastal_regs.pdf.
Accessed 22 February 2021)

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USACE–Wilmington District (NC) 24 Avon Village, Dare County (NC)
NC Laws and Regulations for Activities in the Coastal Zone (Table 1.3 continued)
Name Administering Agency Purpose
1990
Coastal Barrier
Improvement Act
(CBIA)
(Reauthorized the
CBRA)
USFWS / US
Department of the
Interior
 To add new areas to the CBRS in Puerto Rico, the U.S. Virgin
Islands, and the Great Lakes
 To expand the existing CBRS alo ng the Atlantic and Gulf coasts
 To designate a new category called otherwise protected areas
(OPAs), areas established under federal, state, or local law, or
held by a qualified organization, primarily for wildlife refuge,
sanctuary, recreational, or natural resource conservation
purposes
(NFIP Coastal Regulations –1968 to Present. (2010). NC Cooperating
Tech. State.
www.ncfloodmaps.com/pubdocs/fact_sheets/coastal_regs.pdf .
Accessed 22 February 2021).
Coastal Area
Management Act
(CAMA) (1974)

NC Division of Coastal
Management
(NCDCM)

NC Department of
Environment &
Natural Resources
(NCDENR)
 To establish a cooperative program of coastal area
management between the state of North Carolina and local
governments
o The state establishes Areas of Environmental Concern
(AEC’s), such as wetlands, estuarine waters, renewable
resource areas, fragile or historic areas, waterways to
which the public may have rights of access, natural
hazard areas, and Primary Nursery Areas
o Local government takes initiative for planning. State
government shall act primarily in a supportive standard -
setting and review capacity, except where local
governments do not exercise their initiative
 To apply to all 20 coastal counties and all mun icipalities located
within them
 To develop a program of permit review and coordination within
areas of environmental concern
(NFIP Coastal Regulations -1968 to Present. (2010). NC Cooperating
Technical State.
www.ncfloodmaps.com/pubdocs/fact_sheets/coastal_regs.pdf .
Accessed 22 February 2021).
Specific coastal management provisions under CAMA are:
Dredge and Fill
Regulations
NCDCM / NCDEQ
NC Admin. Code tit. 15A, r. 7H.1500. A general permit allowing
excavation within existing canals, channels, basins , and ditches in
estuarine/ public trust waters to maintain previous water depths.
NC Admin. Code tit. 15A, r. 7K.0401. Exempting the USACE from
permit requirements regarding maintenance of federal navigation

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USACE–Wilmington District (NC) 25 Avon Village, Dare County (NC)
channels, including dredging and disposal of dredged materials in
Areas of Environmental Co ncern (AECs).
NC Admin. Code tit. 15A, r. 7M.1100. Under General Policy Guide -
lines (Coastal Area): Providing that excavation/ maintenance
material from navigation channels be used in a beneficial way.
Dune Creation/
Restoration
Regulations
NCDCM / NCDEQ
NC Admin. Code tit. 15A, r. 7M.0202. Under General Policy Guide -
lines (Coastal Area): Allowing dune creation as a temporary
measure to counteract erosion, but only to the extent necessary to
protect property for a short period of time until threatened
structures may be relocated or until the effects of short -term
erosion event are reversed.
Near Shore Sand
Mining
Regulations
NC Division of Marine
Fisheries (NCDMF)
NCDEQ
NC Admin. Code tit. 15A, r. 7H.0106, 7H.0208. Submerged lands
mining rules for estu arine and public trust waters.
NC Admin. Code tit. 15A, r. 7M.1201 -1202. General Policy Guidelines
(Coastal Area): Ocean Mining Policies for federal and state waters
(applicable for federal consistency).
Public Access
Regulations NCDCM / NCDEQ
NC Admin. Code tit. 15A, r. 7M.0201 -0202. Shoreline Erosion
Policies. The following are required with state involvement
(funding or sponsorship) in beach restoration or sand nourishment
projects: (a) the entire restored portion of the beach shall be in
permanent p ublic ownership, and (b) it shall be a local government
responsibility to provide adequate parking, public access , and
services for public recreational use of the restored b each.*
*Exception: The National Park Service manages parking and public
access within the Cape Hatteras National Seashore.
Sand Scraping/
Dune Reshaping
Regulations
NCDCM / NCDEQ NC Admin. Code tit. 15A, r. 7H.1800. N.C. A General permit allowing
beach bulldozing needed to reconstruct or repair frontal and/or
primary dune systems.

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2.0 SCOPE OF REVIEW FOR NATIONAL ENVIRONMENTAL POLICY ACT (NEPA)
2.1 Determination of Scope of Analysis for National Environmental Policy Act (NEPA)
Scoping is an early and open process to d etermine the breadth of environmental issues and alter natives
to be addressed in a National Environmental Policy Act (NEPA) document. Scoping is used to identify
which issues need to be analyzed in detail and which can be eliminated from in -depth analysis. For this
project, the Dare County Board of Commissioners, the County’s engineering consultant (CSE), and state
and federal natural resource agencies used scoping to:
1) Address the purpose, goals , and impacts of the proposed activity
2) Affirm assignments between the County, engineering consultant, USACE and NPS officials,
and other participating agenc ies
3) Identify related projects and associated documents
4) Identify permits, surveys, consultation, and other requirements , and
5) Create a schedule that allows ade quate time to prepare and distribute the EA for public review
and comment before a final decision is made.
In considering the proposed nourishment project, the applicant and its consultants used their extensive
knowledge of the project area b ased on experience with similar projects in the Outer Banks since 2004 and
successful completion of the nearby 2017–2018 Buxton nourishment project. The proposed Avon project
draws on field surveys and an erosion assessment along Avon (CSE 2020), the Environmental Assessment
(USACE-DOI-NPS 2015), and monitoring efforts following the 2017–2018 Buxton project (CSE 2018, CSE
2019a, CSE 2020) and planning of other recent Outer Banks nourishment projects . This review was
conducted to assess prior work , evaluate beach he alth indicators, and monitor the sta bility of the beach,
including after tropical storms and hurricanes .
The proposed Avon project is the first nourishment to be implemented at the instigation of village
representatives and the Dare County Board of Commis sioners. It intends to widen the oceanfront beach
and restore an erosion buffer to reduce closures and chronic damage to Highway 12 as well as federal,
state, and county infrastructure.
The proposed project will fall under the guidelines included in NPS’s issuance of a programmatic EIS
(NPS 2021 ab) for sediment management activities along CHNS . Avon is specifically referenced by NPS
(2021a) as an erosion hot spot along Hatteras Island that is likely to require nourishment for purposes of
maintaining access to National Seashore facilities.
The proposed project will be implemented using the same construction method (ie – offshore dredging)
during the same construction w indow (ie – summer months) as the planned Buxton renourishment
project (under a separate permit application —SAW-2021-01266). It will involve the excavation of beach
quality sand from an offshore borrow area near Avon Village via hydraul ic or hopper dredge see Fig 1.2).
Borrow sediment will be pumped to the beach and spread by land -based equipment (eg – bulldozers)
in the beach zone between the dune crest or upper dry sand beach, and the low water mark. The

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USACE–Wilmington District (NC) 28 Avon Village, Dare County (NC)
elevation of the nourishment berm will be set at or below the normal dry beach level so that it is
naturally overtopped by waves during minor storms. The nourishment profile will adjust rapidly to
prevailing wave conditions, resulting in a gradual shift of sand into deeper water as the profile
equilibrates. Backshore areas are expected to be enhanced gradually after construction by natural
sand delivery from the widened beach. A section of the project beach will include reconstruction of a
protective dune where previous dunes have been lost to erosion.
The project will encompass 13,200 linear feet (~2.5 miles) from near Mile Post (MP) #57 to ~4,000 feet
south of MP #59 (see Fig 1.2). The northern ~4,000 linear feet (~0.76 miles) of the project are
immediately north (upcoast) of Avo n Pier, and the rest of the project area (~9,200 linear feet) will be
south of the pier to the village boundary with the undeveloped section of the National Seashore.
Maximum nourishment volume will be 1.0 million cubic yards, and the maximum average fill density
(volume of nourishment per linear foot of beach) will be ~75 cy/ft, which is equivalent to an average
beach width increase of ~60 ft after natural profile adjustment. The anticipated maximum impact area
through the entire construction process for a 2.5-mile-long project is ~100 acres, among which ~15 acres
represents new dry-beach habitat and ~3.5 acres represents new foredune habitat . However,
construction will move along the beach so that different smaller portions (eg ~300 linear feet of beach,
or <~4 acres) of the ~100 acre impacted area will be affected at different times. The environmental
impact zone of the project encompasses ~700 acres, considering the extra area in the outer littoral zone
that may ultimately experience onshore -offshore sand exchange after completion of construction. The
maximum scale is expected to provide approximate ly five years of erosion relief, dune growth, and NC
Highway 12 protection under normal conditions. The final project volume will be determined accord ing
to state and federal permit conditions, the County’s available construction funds, and the bids
submitted by contractors.
The proposed borrow area for the nourishment project is east-northeast of Avon Pier 2–3 miles offshore
within state waters as delineated in Figure 1.2. Sediment quality is similar to the existing beach in terms
of grain size distribution and color (see Figures 1.5 –1.7 and Appendix A). The applicant has obtained 12
borings to 10 ft below the substrate and additional shallower bor ings to confirm that sediment quality
exceeds North Carolina Department of Environmental Quality (NCDEQ) standards. Additional cultural
resource and geophysical surveys were conducted in July 2021 to ensure no impacts on culturally
significant sites, hard bottom, or other protected resources. The anticipated borrow area will be
approximately ~250 acres in two contiguous sections with excavation depths ~10 ft and 6 ft (by section)
below the existing substrate. The proposed borrow area is within an unnamed shoal complex having
considerable natural relief. Excavations are not expected to leave deep holes relative to the
surrounding topography.
The proposed Avon project will require summer dredging because of safety issues, including the lack of a
nearby safe harbor for ocean dredges and offshore crew members. Construction duration is expected to be a
maximum of ~3 months if work is permitted between 1 May and 30 September. Construction will be bid to allow
work in either the summer of 2022 or the summer of 2023. The preferred start date for construction is May 2022,

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USACE–Wilmington District (NC) 29 Avon Village, Dare County (NC)
but the final schedule is dependent upon dredging companies’ workloads which normally have substantial lead
times and tend to reflect on the bid prices. For example, the initial 2017–2018 Buxton nourishment project was
bid for work in either the summer of 2016 or the summer of 2017. The lowest bid for the 2016 schedule was
~$12 million higher than the lowest bid for the 2017 schedule, therefore, the County elected to enter into an
agreement with the contractor for construction starting in the summer of 2017. The Avon construction
schedule is intended to piggy-back with a planned renourishment at Buxton (SAW-2021-01266) so as to
combine dredge mobilization and effect certain economies of scale.
2.2 Determination of the “Project Area” for Section 7 of the E ndangered Species Act (ESA)
The Endangered Species Act (ESA) (16 USC 1531 et. Seq.) mandates that all federal agencies consider the
potential impacts of an action on federal lands on the species listed as threatened or endangered. The
Proposed Action would impact the beach and inshore zone where certain threatened and endangered
species may be present during part of their life cycles. Because of the potential advers e impacts if
construction occurs when certain species are present, the Applicant has identified and evaluated
biological resources at risk under a Biological Assessment (BA) (Appendix E of this EA). Formal consultation
with USFWS under Section 7 of the End angered Species Act is required for projects of this type. The
Biological Assessment (Appendix E) is required to assist federal resource agencies in evaluating the impacts
of the project and to enable a biological opinion (BO) regarding whether the project would or would not
jeopardize the continued existence of a threatened or endangered species. The BO is a prerequisite for a
decision by the US Army Corps of Engineers to issue a permit for construction. Biological resources
addressed in the BA and present Environmental Assessment include terrestrial, intertidal and subtidal
species, along with identification and special attention to threatened and endangered species, particularly
nesting shorebirds and sea turtles. The BA addresses the habitats on which bi ological resources of the
Action Area depend.
This EA is presenting the No-Action alternative and two action alternatives for consideration for the
proposed project. The two action alternatives are for beach restoration along the Village of Avon and
its ocean shoreline which is under the control of the Cape Hatteras National Seashore. The action
alternatives were designed to augment the natural supply of sand along the ocean beach and reduce
the frequency of dune breaches and storm damages to NC 12 and com munity infrastructure. The
Environmental Assessment examines three alternatives:
 Alternative 1 –No-Action
 Alternative 2 –Winter Construction
 Alternative 3 (Preferred Alternative)–Summer Construction
Additional alternatives were considered during the earl y stages of planning, but were dismissed from
further analysis based on extensive reviews and planning for the nearby 2017–2018 Buxton project
(USACE-DOI-NPS 2015).

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Portions of th e 2017–2018 Buxton project were built efficiently by direct pumping from the borrow area
using a traditional suction -cutterhead dredge and submerged pipeline. Such dredges are less likely to
entrain endangered species (USACE 2010). However, given the inclement sea conditions during
construction , the 2017–2018 nourishment also re quired hopper dredges for extended periods to complete
work in the fall and winter. Non-capture sea-turtle trawling was required for hopper dredge operations,
and the 2017–2018 project was completed without any sea-turtle takes with up to two hopper dredges
used by the contractor (Weeks Marine ). The Avon project is similarly planned with a borrow area close
enough to shore that either cutterhead or hopper dredges could potentially perform construction.
Hopper dredges have taken sea turtles while operating , including numerous takes at the mouth of the
Chesapeake Bay (NMFS 2003 , USFWS 2007 a, USACE 2008). The nature of channel dredging at confined
entrances and the unavoidable concentration of sea turtles at the mouth of estuaries increase the chance
of dredge and turtle encou nters. Turtle concentrations tend to be lower in open-ocean and offshore
borrow areas, such as the proposed sand source for Avon. The 2011 Nags Head nourishment project
involved hopper dredge operations between May and October , but was conducted without any turtle
mortalities by the dredges. The 2019 Nags Head renourishment project used two hopper dredges between
May and August 2019, and one turtle was taken 10 August (CSE 2019b). Therefore, the threat to sea turtles
of projects like the proposed activity is recognized by the applicant.
T he applicant prepared a Biological Assessment (BA) (Appendix E) in connection with the proposed
project and anticipates a request by the USACE to USFWS and NMFS for formal Section 7 consultation
when th e USACE permit application is placed on public notice. Officials at USFWS and NMFS have been
involved in pre -application meetings and have had opportunities to provide input prior to completion
of the BA and EA.
As applies to Section 7 of the ESA, t he scope of the proposed project area is demarcated by the alongshore
project boundaries and the designated offshore borrow area as shown in Figure 1.2. This 2.5-mile beach
includes most of the 3.4-mile shoreline fronting the Village of Avon. The Cape Hatteras National Seashore
has jurisdiction over all beachfront area along Hatteras Island, including the Village of Avon.
The design beach width throughout the planned nourishment area would range between ~40 ft and 90 ft
after normal profile adjustment. The no rth and south ends of the project would taper gradually back to
the existing shoreline over a minimum distance of 500 ft. Sand would be placed in a normal configuration ,
which closely matches the grad es and slopes of the native, dry -sand beach between the toe of the
foredune and mean high -water line.
Designated, endangered , threatened , and species of concern with the potential to occur within the
proposed project area are the roseate tern (E-endangered), red knot (T –threatened), piping plover (T),
American peregrine falcon (E), gull-billed tern (T), Caspian tern (T), common tern (E), eastern black rail (T),
and bald eagle (T). Fish species of concern include Atlantic sturgeon (E), shortnose sturgeon (E), and giant
manta ray (T). Several species of sea tu rtles are afforded extra protection , including the green (T),
hawksbill (E), Kemp’s ridley (E), leathe rback (E), and loggerhead (T ). Also, various species of whales and

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USACE–Wilmington District (NC) 31 Avon Village, Dare County (NC)
mammals may migrate through or close to the area , including blue whale (E), finback (E ), humpback (E),
North Atlantic right (E), sei (E), and sperm whale (E), and the West Indian manatee (T). Habitat exists for
the seabeach amaranth (T) an d seabeach knotweed (E), although there have been no instances of their
occurrence docu mented (USACE-DOI-NPS 2015). A state-protected species, diamondback terrapin (SC–
state listed species of concern), has also been found in the project vicinity. The applicant recognizes that
dredge location or operations may pose an obstacle to the nesting, feeding, o r migratory movements of
these species, but it is far less like ly to affect the sturgeon and the whales than the loggerhead sea turtle.
Protections for the loggerhead and various other species are discussed elsewhere in this EA and in
Appendix E (Biological Assessment).
Section 7 of the ESA would also apply to the proposed project’s water acreage and ocean bottom within
the boundaries of the borrow areas and to the dredges’ nautical locations offshore of Avon beach. The
dredge would relocate accord ing to the project construction plan and if dredging operations were to affect
an endangered species. The borrow area is located off Avon (2‒3 miles offshore) within the 3-nautical-
mile limit, and therefore do es not fall within federal waters .
2.3 Determination of Permit Area for Section 106 of the National Historic Preservation Act (NHPA)
The scope of the permit area for Section 106 of th e NHPA is demarcated by the project boundaries and the
designated offshore borrow areas illustrated in Figure 1.2. As a condition of any federal and state permits
for the proposed project, the applicant, through the US Army Corps of Engineers (USACE), must consult
with North Carolina’s State Historic Preservation Office (S HPO) regarding potential cultural resources that
may be present or impacted in the general vicinity of the project under Section 106 of the NHPA.
Cultural resources encompass archaeologic al and historic objects which m ay exist within the project area,
including the offshore borrow areas where dredging operations occur. The applicant consulted with SHPO
regarding the proposed project in the onshore construction area and the offshore borrow area for the
2017–2018 Buxton nourishment project . The applicant contracted for a cultural resources survey of the
proposed borrow areas and an inventory of historical buildings and shipwrecks that may be present in the
proposed project area (Appendix G‒Cultural Resources Survey). Per state requirements for borrow area
confirmation (15A NCAC 07H.0312 Technical Sta ndards for Beach Fill Projects), the survey included
magnetometer, shallow seismic and side scan-sonar geophysical data collection , and identification of any
targets which may represent debris, fishing gear, undersea cables , or shipwreck remains.
Field investigation identified three magnetic anomalies inside the proposed borrow area, and three
within the 200-ft perimeter of the borrow area. All six anomalies represent very small ferrous objects.
None appear to represent a potentially significant s ubmerged cultural resource and therefore,
no avoidance was recommended . Analysis of the acoustic data identified no evidence of sonar targets
in the borrow area or its immediate vicinity. Consequently, no potentially significant submerged
cultural resources will be impacted by dredging in the proposed borrow area or its adjacent 200 -ft
buffer.

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3.0 PURPOSE AND NEED
3.1 Purpose and Need for the Project
The purpose of the proposed project is to restore sand losses due to chronic erosion and accelerated
erosion during the past decade south of Avon Pier . The proposed project goals are to:
 Provide a wider beach and buffer storm waves along a critically ero ding section of
Hatteras Island.
 Reduce the frequency of storm damages to North Carolina Highway 12 (NC 12) and
existing community infrastructure .
 Replace chronic erosion losses and augment the regional supply of beach sand by using
a non-littoral borrow source of compatible sediments from an off shore borrow area.
 Provide a higher level of storm protection.
 Provide a wider recreational beach and create more habitat for wildlife .
 Integrate a dune management plan into the nourishment design .
Completion of the proposed project will serve as an important step toward the County’s implementation of
a long-term strategy for beach maintenance and protection of Highway NC 12 along Hatteras Island.
Under federal and state requirements, Dare County has submitted a permit application to the USACE and
NPS for the proposed project to nourish the Avon project area. The proposed project will fall under the
guidelines included in NPS’s issuance of a programmatic EIS (NPS 2021ab) for sediment management
activities along the Seashore, which was finalized by ROD in May 2021. Before the USACE can issue a permit
allowing beach nourishment, it must consider and assess the potential impacts of the action on the natural
and human environments pursuant to the National Environmental Protection Act (NEPA). The USACE
permit would be issued in coordination with USFWS and NMFS to determine whether the proposed project
meets the standards a nd requirements for issuance of a major permit for construction activities in critical
areas and in the coastal zone (eg – Section 404 of the Clean Water Act). State action and a permit for
construction in state waters are required under the NC Coastal Ar ea Management Act (CAMA), which is a
prerequisite for the federal permits.
3.2 Historical Erosion Rates and Present Beach Conditions
The applicant evaluated beach erosion in two fundamental ways. First, erosion was estimated for various
dates using historical charts and aerial photographs to delineate shoreline positions. These positions are then
compared against a fixed reference point or line to yield changes over various time periods. It is common
practice to “annualize” the data and determine rate s of change per year so that the results from random time
intervals are comparable. Secondly, profiles across the active beach zone were used to measure the
volumetric condition of the beach. For each surveyed profile it is possible to determine the rela tive condition
of the beach from section to section using the concept of “unit volumes” (ie – the quantity of sand contained
in a one-unit length of beach between referenced contours). Differences between profiles provide a

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USACE–Wilmington District (NC) 34 Avon Village, Dare County (NC)
quantitative measure of the sand deficit between healthy sections of the beach and highly eroded sections
relative to some target or ideal volume (Verhagen 1992, Kana 1993).
3.2.1 Methodology
Five reaches along Avon were delineated based on the geographic locations and the volume a nalyses as
shown in Figure 3.1. Reach 1 is Seashore undeveloped land managed by the National Park Service (NPS)
immediately upcoast of Avon Village. Reaches 2 and 3 cover 9,500 ft of the village north of Avon Pier and Reach
4 is the highly eroding section extending ~8,000 ft south of Avon Pier to Askins Creek North Drive. Reach 5
encompasses the 3,000 ft of shoreline from Askins Creek North Drive into the undeveloped Cape Hatteras
National Seashore.
CSE (2020) used the project baseline to reference shore line positions depicted on various historical aerial
photographs. Following standard practice, shoreline position from photographs generally references a
morphologic feature. Two commonly identified points are the seaward vegetation line, which usually
corresponds to a point near the foredune crest along Hatteras Island, and the “dry -sand wet-sand” contact
line on the active beach which approximates mean high water. CSE also reviewed shoreline change rates
determined by others using similar map/photo sources and methodology.
Erosion analyses based on controlled aerial photography may not represent consistent positions . Figure 3.2
shows a sequence of idealized profiles as they evolve over a storm period. The initial profile includes a
vegetated dune, dry-sand beach, and sloping beach face. Mean high water (MHW) falls along the sloping
beach some distance seaward of the dry beach level. This reflects the fact that breaking waves produce runup
above the high tide level pushing sand to a higher elevation. If a storm impacts the profile, the sloping beach
cuts back leaving a low scarp (2nd panel). Given sufficient time during a storm, the scarp may cut back to the
base of the dune. Further erosion then undermines the foredune leaving a narrow remnant (4th panel). Mean
high water shifts landward in proportion to the intensity of the storm as illustrated in Figure 3.2. If a large dune
is present, it will take a major storm to erode it away. After the dune crest is lost, storm waves can overtop the
remnant feature and drive sand inland producing a “washover” and depositing sand inland. Delineation of
MHW shoreline, therefore, depends on the stage of the beach cycle and whether the imagery was obtained
before or soon after a storm. Note that in these examp les, the seaward vegetation line along the dune does
not move as much as MHW until the dune is washed away (bottom panel).
Because shoreline position interpretation from aerial photos or historical charts can be problematic, short
time intervals between aerial photos will tend to yield more variable rates of change than long time intervals.
The official erosion rates for Avon utilize a ~60–65-year period to eliminate some of the errors
associated with the stage of the beach at the time of the availabl e photography (NCDENR 2012;
https://deq.nc.gov/about/divisions/coastal-management/coastal-management-oceanfront-shorelines/oceanfront-
construction-setback-erosion-rate, accessed July 2021).

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FIGURE 3.1. Map of the Avon project vicinity showing the “Hatteras Island baseline” (CSE 2013) and stationing in
engineering form. Bathymetric survey lines of the present study are shown in the figure. Five reaches were delineated
based on the beach survey analyses. The preliminary offshore sand search area is marked by the blue box, and the blue
dots represent the reconnaissance core locations. Red dots along the beach show the locations of sand sampling. Offshore
coring and sand sampling on the beach are discussed in Appendix A – Geotechnical Report.

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FIGURE 3.2. A sequence of beach conditions associated with erosion eve nts illustrating the greater
variation in “shoreline” position using mean high water (red arrows) versus the seaward vegetation
line (green arrows). [Source: CSE©].

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TABLE 3.1. Historical accretion (+) and erosion (–) rates for Avon at ~1 nautical mile (ie – one minute of latitude) transects using
high tide lines as determined by US Coast and Geodetic and present -day NOAA surveys. Results in meters per year; 1 meter =
~3.28 ft. [Source Everts et al 1983].
3.2.2 Official Shoreline Change Rates
NC Department of Environmental Quality (NCDEQ – formerly NC Department of Environment and
Natural Resources – NCDENR) periodically publishes official, long-term, average annual oceanfront
erosion rates (“setback factors”) for Nort h Carolina. An early analysis was prepared by Tafun et al
(1979) who applied the “end -point method,” which was retained by NCDENR in subsequent updates.
The end-point method computes average annual rates at each shoreline transect using the earliest and
most-current shoreline position. The earliest shorelines considered in prior analyses are typically
based on NOAA’s National Ocean Service (NOS) “T-sheets” from the 1920s to 1930s. More recent
shorelines are interpreted from controlled aerial photography using the “wet/dry” line at the edge of
the surf zone. This line approximates local MHW at the time of the photography (Overton and Fisher
2003). NCDENR (2012) details the various blocking and smoothing algorithms applied in developing
official rates along Dare County. That study utilized imagery from 1946/49 and July 2009 (endpoints),
which predated a series of significant storm events over the past decade (eg – Hurricane Sandy 2012;
Matthew 2016). Figure 3.3 shows the results of the NCDENR (2012) ana lysis and is included here to
illustrate the variability along Hatteras Island near Avon.
A striking aspect of the NCDENR (2012) shoreline change rates along Hatteras Island is their large
variation alongshore. Long barrier islands with few active inlets often exhibit more uniform shoreline
change rates (Hayes 1994). This is certainly the case north of Oregon Inlet along most of Bodie Island
or along Bogue Banks (NCDENR 2012). By comparison, some short segments of Hatteras Island have
zones of moderate accretion (>5 ft/yr) in close proximity to zones of high erosion (>10 ft/yr). The Avon
area illustrates both conditions. Avon extends from NCDENR stations ~7315 to ~7425 (See Figure 3.3).
The south half of the Avon project area experienced erosion at 2 –5 ft per year between 1949 and 2009
(NCDENR 2012, Fig 3.4–3.6). By comparison, the north half of Avon accreted at 1 –4 ft/yr during the same
period. This result is consistent with findings of Everts et al (1983), who determined rates for 1949 –1980
at five transects along Avon (by 1.0 -minute latitude intervals, or every ~6,000 ft) (Table 3.1).

Latitude Location 1849–1915 1849–1980 1915–1949 1915–1980 1949–1980
35° 22΄ North Avon 4.0 0.2 –8.5 –3.9 1.2
35° 21΄ ~ Pier 0.8 –0.5 NO –1.9 NO
35° 20΄ –0.1 –0.3 –1.3 –0.6 0.1
35° 19΄ 0.3 –1.0 –3.2 –2.0 –1.1
35° 18΄ South Avon –0.4 –2.0 –5.6 –3.7 –1.4
Mean Ocean Shoreline Changes from Oregon Inlet to Cape Hatter as
1852–1917 1917–1949 1949–1980 1852–1980
0.4 –2.9 –1.3 –1.1

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FIGURE 3.3. Long-term shoreline change rates for Hatteras Island around Avon derived from historical aerial photography (1946/49 and
2009) showing smoothed and blocked data by transect as prepared by NCDENR and their consulta nts. Shoreline segments in red exhibit
long-term erosion, whereas, green indicates accreting areas. Avon, situated between transect IDs ~7320 and 7420, shows trends of erosion
along the southern half of the community and accretion north of Avon Pier. [So urce: NCDENR 2012]

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The Everts et al (1983) “30 -yr” shoreline change rate for Avon (1949 –1980) ranged from (+)1.2 to (–)
1.4 meters per year (~+3.9 to –4.6 ft/yr). NCDENR (2012 ) “60-year” rates, using 1949 –2009 imagery,
ranged from (+)5.5 to (–)4.5 ft/yr. NCDENR (2012) published “setback” factors for Avon based on these
data (Fig 3.4). Stable and accreting areas are assigned a 2 ft/yr setback factor irrespective of the
specific accretion rate. Figure 3.4 shows the highest erosion along South Avon at 4.5 ft/yr (Note Avon
Pier is situated near Dune Way where the rates go from 2 to 3 ft/yr at the left -center of the graphic).
The graphic also indicates prior maximum erosion at 3 ft/yr for the 2003 rates. Thus, the official
erosion rates as determined by NCDNR increased between 2003 and 2011, particularly in the area
south of Avon Pier.
NCDEQ-Division of Coastal Management (NCDCM) now maintains a web -link to linear erosion rate d ata
for Dare County (NCDENR 2012; https://deq.nc.gov/about/divisions/coastal -management/coastal-
management -oceanfront -shorelines/oceanfront -construction -setback -erosion-rate , accessed July
2021). There have been slight increases in official erosion rates since the 2012 maps were published
(Fig 3.5). For example, the maximum setback factor has increased from 4.5 ft/yr to 6.0 ft/yr along south -
central Avon as of 2020. Accretion remains the predominant trend north of the pier and along the
Seashore at the south end of the village. Data on the NCD EQ website show continued accretion along
north Avon at rates up to 4.6 ft/yr near Wahoo Circle. The highest official erosion rate (2020) is 6.6 ft/yr
in the Ocean View Drive neighborhood near Pampas Drive around 4 ,000 ft south of Avon pier.
The present prorated average official erosion rate (or “setback factor”) along south Avon is ~4.7
ft/yr. It can be shown that these linear change rates can be converted to equivalent volumetric
rates in the Avon setting. Usi ng an adopted ratio of dry beach loss to volumetric loss (1.15) yields
an average annual loss rate of roughly 5.4 cy/ft/yr along south Avon (applicable to ~10,750 lf). For
preliminary planning purposes, the applicant applied approximately this value for the initial project
formulation (ie – “Advance” nourishment requirement, USACE 2008).

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FIGURE 3.5. NCDEQ official erosion rates (“setback factors”) in feet per year for Avon. Note ~35 percent increase since the
2012 condition and ~100 percent increase since the 2003 condition on Figure 3.4. [Source: NCDCM 2020]

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3.2.3 Recent Variations in Shoreline Change Rates
As the previous section describes, official erosion rates (setback factors) have increased along Avon
between 2003 (NCDENR 2012) and 2020. North Avon remains healthy and accretional, but south Avon
exhibits roughly 100 percent higher official erosion rates than 20 years ago. Official state rates
appropriately consider a relatively long period of time (40 –70 years) in the analysis to avoid short-term
bias associated with storm events and seasonal variations in the high water line.
The applicant completed an independent analysis of shoreline change, using a combination of published
lines and aerial photo interpretations. A total of 12 dates of surveys and imagery were utilized spanning
the years 1980 to February 2020. Everts et al (1983) performed a rigorous analysis of earlier shorelines
and presented average rates for several periods between ~1850 and 1980 (See Table 3.1).
NCDCM shapefiles were downloaded and digitized to generate a set of historical shoreline maps for
the project area (Figure 3.6 – 2 pages). Each panel includes the “1852” and “1946” shoreli nes for
general comparison. The Avon project baseline was used to measure offset distances to each
shoreline at 500 ft intervals.
Results for individual stations were averaged by reach, using five segments of shoreline exhibiting
similar trends of accre tion or erosion (see Fig 3.1). A cursory view of the shoreline maps (Figure 3.6)
shows that the 1852 and 1946 shorelines fall well seaward of recent shorelines along south Avon, but
track close to recent shorelines along the north end of the village. To help distinguish recent trends,
the applicant plotted the average shoreline position over time along each reach (CSE 2020). The first
graphs (Fig 3.7 upper and lower) plot the data from the earliest two surveys to the present (from 1852
and 1946, respecti vely). These graphs confirm the “century” trends of shoreline advance north of
Avon and “75 -yr” advance since the 1940s along north Avon. All other reaches exhibit shoreline
retreat since the 1850s or 1940s. The other distinct trend is accelerated reces sion along south Avon,
starting around 2000.
Figure 3.8 plots the data for “Forty -Year” and “Twenty-Year,” periods along with trend lines to isolate
change rates by reach for each period. The graphs also include an overall average for Reaches 3 –5
which represent the principal project area extending from Station 1555+00 (~3,500 ft) north of Avon Pier
to the approximate southern village limit. Reaches 1 and 2 at the north end of the study area generally
show accretion for all periods. Earlier data have bee n omitted in each graph to isolate the trends for
the period.
The “Forty-Year” and “Twenty -Year” trends show an increase in average erosion rates from ~7.5 ft/yr
to 10 ft/yr (Fig 3.8) along Reaches 3 –5. Reach 4, encompassing ~8,000 lf between stations 15 90+00
and 1670+00 south of Avon Pier increased from ~10.7 to 14.4 ft/yr. These rates are higher than official
erosion rates (described in Section 3.2.2) because they encompass shorter time periods. As the
graphs depict, shoreline retreat was at a slower rate in the 1980s and 1990s compared with the 2000s
and 2010s.

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FIGURE 3.6a. Historical shorelines for the Avon area used in the present analysis (various sources) as given in the text.
The worst erosion along Avon in recent years has impacted a ~4,000 lf section from ~1,000 to 5,000 ft
south of Avon pier. Figure 3.9 shows the change in shoreline position for representative stations in this
area since 1997. Stations closest to the pier (Fig 3.9 upper) show recession rates averaging over 17 ft/yr
(1997–2020). At 3,000–4,000 ft south of the pier this “Twenty -Year” trend is ~16 ft/yr recession. These
results are in distinct contrast to changes between 1946 and 1998 (Fig 3.9 lower). The limited data
available show a recession in this same area at under 3 ft/yr for the earlier period.

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FIGURE 3.6b. Historical shorelines for the Avon area used in the present analysis (various sources).

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USACE–Wilmington District (NC) 45 Avon Village, Dare County (NC)
FIGURE 3.7. Changes in average shoreline position by reach along Avon for 1852 to 2020 (upper) and 1946 to
2020 (lower). Note the general acceleration of erosion for most reaches since 2000.

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FIGURE 3.8. “Forty-Year” and “Twenty -Year” erosion trends for Avon averaged by reach. The value before the “x” in each
equation is the erosion (or accretion) f actor in feet per year. Rates in the black boxes are averages for Reaches 3, 4, and 5, the
main reaches of interest.

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FIGURE 3.9. Trend in erosion for two periods at stations within the most critically eroded section of beach. Note much
higher rate of retreat for 1997–2020 compared with 1946 to 1998 (lower).

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3.2.4 Rhythmic Shoreline Changes
The previous section evaluated shoreline positions by Reach using averages of numerous points along
the shoreline. A characteristic of Hatteras Island beach is systematic variation i n visible beach width in
the longshore direction. This variation was apparent in February 2020 orthorectified aerial photos (CSE
2020). Figure 3.10 shows conditions on February 18th along the critically eroded section of Avon south
of the pier. Three or four sections of the beach were considerably wider than adjacent areas that day,
particularly around stations 1620+00, 1650+00, and 1675+00.
Rhythmic beach features alongshore occur at various scales and are generally associated with inshore
bathymetric variations and the particular stage of the beach cycle* (Wright and Short 1983). Where an
offshore bar is higher or closer to shore, the dry -sand beach in its lee will tend to be wider. Conversely,
where the bar is lower or missing, more wave energy can reach the shore and scallop out the visible
beach. Similar features were described by Fenster and Dolan (1993) for the Avon area in a University of
Virginia study. Inman and Dolan (1989) referred to large -scale variations in beach width as “erosion -
accretion waves” and noted there is a tendency for these features to migrate alongshore in the direction
of predominant (or “net”) sediment transport. CSE has documented the scale and magnitude of such
features at Pine Island (Currituck County) and Nags Head (CSE 2015b, 2018).
At Avon, some historical shorelines evaluated by the applicant show an amplitude (beach width)
fluctuation of over 150 ft and wave length (spacing between wide or crest sections) of ~2,500 –3,000 ft
(Fig 3.11). The February 2020 aerial image (Fig 3.10) showed rhythmic shoreline topography at these
scales. Figure 3.10 also shows data for an aerial photo obtained in September 2018. In that case, the
typical amplitude of the features is around 50 ft and the spacing between crests is of the order of 1,000
ft. These differences reflect the seasonality of the beach cycle. The summer is usually a time of beach
buildup under lower wave conditions. This tends to smooth out or fill in erosional arcs and thereby
reduce differences in beach w idth. An aerial photo in September is likely to exhibit less variation in
beach width (unless a hurricane has imp acted before the survey). Fall and winter storms shift sand
offshore and produce more irregular topography in the surf zone. This can lead t o large-scale variations
in visible beach width as illustrated by the 2020 image (Fig 3.10).
[*Beach cycle – Systematic changes in the width and slopes of the visible beach and development of underwater
bars based on changes in wave energy. Generally, thi s refers to the process of onshore -offshore sand transport
between fair weather and storm conditions. If the beach cycle is in balance, there are no net losses of sand in
the littoral zone.]

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FIGURE 3.10. Rectified aerial photo of
south Avon (note pier at the top of the
image) showing large-scale variations
in beach width. These longshore sand
waves or rhythmic topography are
common during certain beach cycles,
particularly in winter after the visible
beach has eroded. They tend to
propagate to the south along Avon in
the direction of predominant sand
transport. [Source: CSE©]

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FIGURE 3.11. Variation in high water shoreline positio n by station for September 2018 and February 2020
illustrating rhythmic longshore variations in beach width (see text for discussion).

Beach width variations described above become important if the seasonal magnitude exceeds the
average beach width. For example, if the “trough” of a longshore sand wave is too deep, it will cut into
the toe of the foredune and potentially impact developed property. Ye t, some short time later, the
same section of beach may widen by 100s of feet as the crest of the sand wave propagates into the area.
The implications of this for the present project is that beach restoration along Avon will likely be subject
to the cyclic and localized beach width variations. Localized accelerated erosion is less likely to
continue without some modulation if adjacent sections of beach are relatively healthy, as is the case at
the upcoast and downcoast ends of Avon beach. The official setback factors published by the state (see
Fig 3.4) are long-term averages and generally well below 10 ft/yr for any point along Avon, and may
alternate between erosion and accretion for particular localities during the same period. The applicant
considered long-term as well as short-term shoreline change rates in developing the proposed beach
nourishment plan.

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3.2.5 Beach Profile Surveys
The applicant measured profiles at 500 -foot (ft) spacing in July 2020 from the foredune to deep
water* from stations 1470+00 to 1700+00, encompassing a total of 23,000 linear feet (~4.35 miles) of
shoreline. The survey area included the ~1.54 miles between the Avon Pier (Station 1588+00) and
Askins Creek North Drive (1670+00) where accelerated erosion has occurred in r ecent years. The 2020
profiles are believed to be the first comprehensive data set for this area and will serve as the baseline
condition for the project .
[*The seawardmost dune and the littoral zone. The littoral zone is subject to active processes of w ave breaking
and observable change in bottom elevation over a given timeframe. The zone is often further divided into the
beachface (or foreshore) which extends from the low water line to the limit of maximum wave uprush; and the
shoreface which extends f rom the low water line out to the depth of closure, or limit of observable change in
bottom elevation. Nearly all cross -shore sand transport occurs within the littoral zone.]
Representative profiles from the July 2020 survey are shown in Figure 3.12. [Se e Figure 3.1 and the
aerial photo insert at the right-hand corner of Figure 3.12 for general locations.] Appendix D – Littoral
Processes contains the entire set of 47 long profiles obtained by the applicant for the present project.
Profiles north of Avon Pier in July 2020 exhibited a well -defined longshore bar with a crest at −10 to −14
ft NAVD positioned ~1,000 to 1,200 ft offshore along the shoreface. This longshore bar broadens and
flattens to the south from Avon Pier with a deeper crest (than the nor thern section) at about −20 ft. The
offshore bar dwindles at the south end of Avon. Instead, a small inshore bar at −6 ft to −10 ft emerges
south of Station 1660+00 in July (see Fig 3.12b). The smaller offshore bar south of Avon Pier likely
contributes to the higher observed erosion in that section of Avon.
Figure 3.13 illustrates the DTMs of the study area by color -coded, smooth-contour maps using the
indicated elevation/depth intervals for each color (Fig 3.13). Light colors indicate the dune -beach zone
and longshore bar; deep blue represents water depths >30 ft. The bathymetry DTMs show relatively
smooth, continuous morphology of a longshore bar (yellow -green color band) (inside the 20 -ft depth
contour) along the northern half of Avon. The longshore bar diminishes to the south and an inshore bar
develops in shallower water.

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FIGURE 3.12a. Representative profiles for the Avon project area. [UPPER] at Station 1530+00 in Reach 2 (north
Avon) showing a foredune extending to +24 ft NAVD and broad dry -sand beach situated ~500−800 ft from the
baseline. A small inshore bar with crest at −10 ft NAVD is positioned ~1,000 ft from the baseline and a well-
developed longshore bar is centered ~2,300 ft se award of the baseline. [LOWER] at Station 1615+00 in Reach 4
(half mile south of Avon Pier) showing lack of dune, escarpment at the dune face, narrow dry -sand beach, and
steeper beach face. The longshore bar becomes flatter with a deeper crest , providing less wave dissipation
than Station 1530+00 and likely contributing to higher erosion rates in recent years south of Avon Pier .

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FIGURE 3.12b. Representative profiles for the Avon project area. [UPPER] at Station 1660+00 in Reach 4 (~1,000
ft north of A skins Creek North Drive) showing a foredune at +24 ft NAVD and approximately 30−50 ft of dry -sand
beach from the toe of the dune. An inshore bar with a broad crest around −12 ft NAVD occurred at this locality
in July 2020. [LOWER] at Station 1685+00 in Reach 5 (near the last house at the south boundary of Avon) showing
a foredune at +24 ft NAVD and approximately 200 ft of dry -sand beach from the toe of the dune. An inshore bar
occurred near the low-tide terrace around −6 ft NAVD . (from CSE 2020)

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FIGURE 3.13. Color-coded topography and bathymetry DTM interpolated from the July 2020 beach condition survey for
the Avon study area. (from CSE 2020)

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FIGURE 3.14. Illustration of the three lenses used in the profile volume analysis for the Avon project.
3.2.6 Profile Volume Analyses of July 2020 Beach Conditions
The Avon 2020 survey prov ided a measure of the volume of sand contained within the project littoral
zone. Volume variations along the Avon project area were estimated using standard methods
(average -end -area method) and common cross -shore boundaries and contour datums. The
applicant adopted the normal limit of significant change in bottom elevation (ie – Depth of Closure –
DOC) for the project areas at −24 ft NAVD.* Therefore, volume analyses are referenced to −24 ft NAVD
encompassing the portion in the longshore bar. Within th is depth limit, three primary lenses (ie –
volumes between particular reference contours) were used for purposes of evaluating the condition
of various portions of the profile as illustrated in Figure 3.14.
Lens 1 – Dune – From the dune crest to dry sand beach at +6 ft NAVD
Lens 2 – Beach – Between +6 ft and low tide wading depth at −6 ft NAVD
Lens 3 – Underwater – Between –6 ft and –24 ft NAVD
(ie – to the closure depth or FEMA reference depth limit)
[*The seawardmost dune and the littoral zone. The littoral zone is subject to active proce sses of wave breaking
and observable change in bottom elevation over a given timeframe. The zone is often further divided into the
beachface (or foreshore) which extends from the low water line to the limit of maximum wave uprush; and the
shoreface which extends from the low water line out to the depth of closure, or limit of observable change in
bottom elevation. Nearly all cross -shore sand transport occurs within the littoral zone.]

Unit volumes along Avon beach were calculated to determine the quantity of sand in one linear foot
of beach at each lens and each survey station. These unit volumes were then used to calculate the
average unit volume along each reach. The unit volumes of the three lenses at each survey station
are listed together w ith the profile plots in Appendix D – Littoral Processes of this document . Unit
volumes were used to compare each reach and determine the sand deficit and formulate the beach
restoration plan .
Figure 3.15 shows unit volumes station by station and reach, c alculated by lens based on the July
2020 survey. The five reaches delineated for the study area are marked in the figures, and the
horizontal lines (in red) show the average unit volume of each reach. The average unit volumes of
each reach are summarized in Table 3.3 .

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FIGURE 3.15. Unit volumes by station along the Avon project area based on the July 2020
survey. [UPPER] Volumes in the foredune. [MIDDLE] Volumes between the dune crest and low tide
wading depth. [LOWER] Volumes between the dune crest and DOC. Averages are given by reach
on the red line. These data illustrate the sand deficit in Reach 4 relative to adjacent reaches.

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TABLE 3.3. Summary of average unit volumes by reach in the three reference lenses along the Avon study area using the
July 2020 survey.

The applicant’s analysis of erosion and calculation of profile volumes provided a quantitative measure
of beach conditions along Avon and helps explain why certain sections of beach are narrower or missi ng
dune protection (see Figures 1.8 –1.10). This analysis served as a basis for project formulation and
consideration of alternatives within the fiscal constraints of Dare County. Key findings included:
1) Erosion has encroached on developed property and inf rastructure along
limited portions of Avon beach and has resulted in loss of storm protection
and increased flooding and road closures.
2) Reach 4 south of Avon Pier has a significant sand deficit in the littoral profile
with respect to adjacent reaches.
3) Erosion has accelerated along Reach 4 during the past 20 years.
4) Beach conditions improve and erosion rates are much lower at the north and
south end of Avon Beach.
5) Volumetric erosion rates are uncertain until more comparative surveys
become available.
The applicant determined that beach nourishment is feasible at a range of levels (design life) and
selected a middle range (“5 -year”) formulation for the initial nourishment project along the Village of
Avon.

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3.3 Basic Project Purpose
The proposed activity is a nourishment project in which an ocean -certified dredge will be extracting
sediment from borrow sites offshore of Avon beach within the three -nautical-mile limit in the Atlantic
Ocean. The sediment to nourish the beach would be pumped onshore and pla ced along a ~2.5-mile stretch
of beach. It would then be shaped by land -based equipment to the grades and slopes that are typical for
a beach in that setting.
3.4 Water Dependency Determination
This determination is to be made in all instances where the proposed activity includes a discharge into a
special aquatic site. Special aquatic sites (as defined in 40 CFR 230.40 - 230.45) are (1) sanctuaries and
refuges; (2) wetlands; (3) mud flats; (4) vegetated shallows; (5) coral reefs; and (6) riffle and pool complexes
(USEPA 1972). The proposed project is not located near special aquatic sites as defined above, nor is it
pumping directly into a special aquatic site. Although the proposed project will involve activities in
oceanic waters, it does not requir e access or proximity to or sitting within a special aquatic site to fulfill its
basic purpose. Therefore, it is not considered as water -dependent based on the above definition.
3.5 Overall Project Purpose
The County of Dare recognizes that the 2.5-mile project area is a major environmen tal and economic asset
for the Outer Banks and Dare County as well as NPS . The proposed project is consistent with the long-
range goals of the County to protect NC Highway 12 and protect the natural environment of the b each.
The nourishment plan will place a maximum of 1.0 million cubic yards on the beach (Figure 1.2). Land-
based equipment will move the sand to shape a “stable” beach * (Figure 1.3) contour that would widen
and expand the acreage of the beach (Figure 3.16 and 3.17). As part of the nourishment design, sand would
be moved to build up the dunes along a limited section of the Village of Avon, making improvements to
the dune system that would enable the beach to better withstand storms and protect property (see Figure
1.3).
*[A stable beach is herein defined as a beach with sufficient width and sand volume to withstand normal yearly fluctuations in its profile
without damage to the foredune. Beaches with insufficient sand volume in their profile have a deficit , which can be approximated by
comparing nearby stable beaches with eroded beaches as discussed in Section 3.2 and Appendix D (Littoral Processes).]
The applicant sees the goal of nourishment as essential in the context of a long-term beach management
plan for Dare County, because the Avon beach provides habitat to a variety of coastal species and benefits
the property owners and visitors who vacation there. The village is part of the lively commercial district
of Hatteras Island , which supports seasonal a nd year-round tourism, and is an important tax base for the
region . In addition, it is desirable for the County to support the restoration of Avon beach to protect
Highway NC 12 and maintain the stability of the beach and improve storm protection for prop erty and
infrastructure. By implementing the plan, the County is seeking to provide long-term protection of real
estate values and the C ounty’s tax base. The overall purpose of the nourishment project is to maintain the
beach at Avon at the same or bette r levels of stability as adjacent healthy sections of beach and to protect
its benefits as an important recreational, environmental, and economic asset in the state and region .

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FIGURE 3.16. Habitat area map of the project area showing acreage of various dune, beach, and inshore habitats out t o the −24
ft NAVD depth contour.

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FIGURE 3.17. Representative habitat profile in the Avon project area showing elevation limits for various habitat types and
corresponding areas along ~13,200 linear feet based on conditions in July 2020.

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4.0 CONSULTATION AND COORDINATION
Federal re gulations require the USACE to involve the interested and affected public in a review and
comment process under the National Environmental Policy Act of 1969 (NEPA). This is being accomplished
as outlined below. A number of federal and state agencies were consulted and solicited for input into the
scoping and alternatives development process. This section documents the prior and present scoping
process for the proposed project and identifies future compliance needs and permits .
4.1 Results of Coordinating on Public Notice
The Avon beach nourishment project was initiated by Dare County in February 2020 after the Buxton
renourishment project (SAW-2021-01266) was initiated. A primary motivation for the Avon project is to
capture certain economies of scale if it can be combined with the Buxton renourishment project which
has a target construction date of Summer 2022 and a contingency time table of Summer 2023 should
bids for construction effect substantially larger savings. The applicant reta ined CSE to prepare a
feasibility study and evaluate alternative nourishment scales and longevities. Preliminary and final
results of the study were presented to Dare County and made public in August and November 2020 (CSE
2020). The study outlined three levels of beach/dune restoration for Avon.
 Emergency Project – 240,000 cy along 8,000 lf using an inland borrow area with the majority
of placement on the subaerial beach and present /former dune areas.
 Mid-term “5-year” Project – 1,000,000 cy along 11,500 lf via offshore dredging.
 Long-term “10-year” Project – 2,200,000 cy along 18,000 lf via offshore dredging.
Following the feasibility study, Dare County officials (applicant) determined that a revised mid -term
project was the most practicable alternative considering the funding availability. The majority of beach
nourishment projects in Dare County have been funded locally by county and municipal funds. The
Avon feasibility study determined that combining construction of Buxton and Avon under the same
timetable would potentially reduce costs by $2 –3 million (CSE 2020). Accordingly, the present EA and
permit application for Avon proposes an implementation and post -project monitoring schedule that
mirrors the nearby Buxton renourishment project. Like the planned Buxton renourishment project, the
Avon project draws on prior public outreach associated with the 2017 –2018 Buxton nourishment
project.
As the first of its kind in decades at Cape Hatteras, the initial Buxton project involve extensive reviews
and coordination with NPS officials and the community under the Planning Environment and Public
Comment (PEPC) process. This was accomplished in 2014 –2015 after Dare County convened public
forums in Manteo (county seat) and Buxton on 18 –19 August 2014, and the park service convened public
forums at the same localities on 27 –28 January 2015. Public comments were solicited during a public
scoping period between 12 January and 27 February 2015. These were invited under formal NPS public
scoping in response to a Notice of Intent (NOI) published in the Federal Register on 29 December 2014,

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pursuant to Section 102(2)(c) of the National Environmental Policy Act (NEPA) of 1969. The Notice of
Intent to prepare an Environmental Impact Statement (EIS) notified the publi c of a request from Dare
County, North Carolina for a Special Use Permit from the National Park Service for activities related to
beach widening in the Buxton area within and adjacent to Cape Hatteras National Seashore. The public
comment period extended to 27 February 2015, and written comments were collected through the PEPC
website (http://parkplanning.nps.gov/caha).
Following receipt of public comments in response to the Notice of Intent, the National P ark Service
met with the US Army Corps of Engineers officials and determined that the Proposed Action (initial
nourishment at Buxton) should be evaluated under one joint Environmental Assessment (EA) by the
USACE and the National Park Service. Accordingly, the National Park Service issued a Public Notice of
Termination (dated 17 June 2015) of the EIS and its intent to prepare the initial EA (FR Vol 80, No 116,
pg 34691).
Over 260 comments on the Proposed Buxton Action were received. The majority of comment s were
concerns about not implementing the project soon enough because of the situation’s urgency. The
public was alerted to watch for updates and information on the Cape Hatteras National Seashore website,
at local media outlets, and on the PEPC website. This process was concluded successfully, and the original
project EA was published and submitted with permit applications on 15 September 2015 (USACE-DOI-NPS
2015). The original project was placed on public notice under joint applications to the US Army Corps
of Engineers (#SAW –2015–01612), state of North Carolina (#CAMA 136 –15), and National Park Service
for a Special Use Permit (#GOV –16–5700–014). All permits for the initial Buxton nourishment were
received between late December 2015 and March 2016. Project implementation occurred between
June 2017 and February 2018.
Following the Buxton nourishment project, t he NPS initiated the draft EIS Regional Sediment Management
Framework for the Cape Hatteras National Seashore in the summer of 2019. The docume nt anticipates
the scale and scope of potential beach nourishment and dune restoration projects that are likely to occur
along the National Seashore during the next few decades. It specifically references projects at Buxton and
Avon among other sites and considers the frequency and cumulati ve impacts of such projects on the
natural resources within Park boundaries. The draft EIS was completed and placed on notice for public
comment in September -October 2020. NPS issued the final EIS in March 2021 and the Record of Decision
in May 2021 (NPS 2021ab). Dare County’s engineer for the Buxton nourishment projects (CSE) served as a
consultant to the NPS team that prepared the EIS and is using the document as a resource and check for
consistency for the present Avon EA document.
On 7 November 2019, a scoping meeting was held between the applicant and USACE, NPS, and other local,
state, and federal agencies to di scuss the general need and rationale for the proposed Buxton
renourishment project. Attending were members of the County, NCDEQ (formerly NCDENR), NCDCM,
NCWRC, USFWS, NOAA –NMFS, NPS, and USACE-Wilmington (Planning Section). Also consulted were
NCDEQ–NCD MF, NCNHP, and SHPO. A timetable w as presented noting the requirements for
environmental review and comment by the USACE, NPS, USFWS, and other federal and state regulatory

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and resource agencies befo re any action could be taken. During the November 2019 scoping meeting for
Buxton, the applicant alerted attendees that a project to address erosion along Avon was also being
considered by the applicant. Other public communications via local media also increased awareness of
the ongoing erosion problems along Avon around that time period (Hampton 2019).
Following completion of the Avon feasibility study in November 2020, the applicant met with NPS officials
on 11 February 2021 (remotely due to the worldwide COVID -19 pandemic) and discussed the potential
scale and scope of the Avon nourishment project and solicited NPS guidance for protection of natural
resources. The applicant received an update of the NPS Programmatic EIS for Sediment Management
along Cape Hatteras National Seashore and received confirmation that Avon Village was one of six NPS
“erosion hot spots” addressed in the EIS (NPS 2021a).
On 24 February 2021, Dare County officials convened a public forum (via teleconference), outlined the plan
for “Mid -term” beach nourishment along Avon Village , and solicited comments from the community. The
majority of the comments related to the proposed tax districts needed to help the County pay for the
project without external funding (R. Outten, County Manager, Dare County, NC, pers comm February 2021).
The forum confirmed widespread community awareness of the proposed project as of February 2021.
NCDEQ convened an inter -agency (pre-application) meeting with federal, state, and local agencies on 4
March (via teleconference) in which the applicant outlined in detail the proposed plan for Avon
nourishment. Attendees included representatives from USACE, NPS, NOAA -NMFS, DOI-USFWS, NCDEQ
divisions including NCDCM, NCWRC , NCDWR, NCDMF, and NCDEACS. The applicant solicited and received
guidance regarding project implementation, environmental protection, endangered species protection,
and post-project monitoring. Various monitoring and mitigation plans described herein incorporate
preliminary comments and guidance from federal and state resource and regulatory ag encies.
The Applicant submitted the DWR Pre -Filing Meeting Request Form on 14 June 2021 in the Clean Water Act
Section 401 Certification Rule. The USACE (Wilmington District) issued Public Notice (SAW -2021-01266) on
28 June 2021 after receiving the Applic ant’s permit application, and the comment period was ended on 28
July 2021.
On 14 July, the applicant met with NPS officials (remotely) and discussed the Avon nourishment plan in
detail preparatory to submission of the final permit application and supporti ng environmental
documents. This liaison included guidance from the NPS (2021 ab) Programmatic EIS for Sediment
Management along the Cape Hatteras National Seashore.
The applicant expects to conduct additional community forums to update the community on th e Avon
project, its funding plans, and the requirements for implementation and protection of the work area.
No ethnographic or Indian Trust resources are known to be present in the project area, so no tribal consul-
tations were required.

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4.2 Additional Issues Raised by the USACE
No additional issues have been raised by the USACE or NPS. In this EA, the applicant is addressing the
primary areas of concern, including summer dredging, sediment quality, issues related to endangered and
threatened s pecies, essential fish habitats, water quality and turbidity, and benthic organisms.
4.3 Comments Raised That Do Not Require Further Discussion
No comments have been received regarding the proposed project prior to submission of this EA.
Therefore, the re are no comments that require further discussion at this time.

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5.0 ALTERNATIVES ANALYSIS
NEPA and Section 404(b)(1) g uidelines require an evaluation of a reasonable range of alternatives and the
effects of those alternatives (including the “No-Action Alternative”) through careful analysis. Discussion of
the “No-Action Alternative” provides a baseline against which the action alternatives can be compared. In
addition, under current North Carolina C oastal Zone Management (CZM) regulations, only three
alternatives are allowed to deal with severe beach erosion : (1) no action (ie – abandonment), (2) retreat and
relocation, and (3) beach nourishmen t. These three alternatives were discussed in detail in the E A
documents for the 2017–2018 Buxton beach nourishme nt project (USACE-DOI-NPS 2015). For the proposed
Avon nourishment project, site selection, screening criteria , and alternatives are evaluated and analyzed.
5.1 Site Selection and Screening Criteria
Any manipulation of the shoreline is recommended only after an analysis of the degree to which such
measures would impact natural resources and coastal processes . This analysis is completed through an
evaluation of alternatives so that an informed decision can be made. In conducting this EA , the applicant
will seek to minimize impacts in the immediate project area and its vicinity.
Site selection was determined by a request of Dare County to construct a beach nourishment project along
a 2.5-mile stretch of shoreline along the Village of Avon and the National Seashore . The applicant seeks to
construct an engineered beach indistinguishable from the natural beach and to provide expanded habitat
areas between the ocean and threatened structures. The one action alternative presented here, “Beach
Nourishment With Summer Construction” (the Preferred Alternative), was developed based on the nearby
2017–2018 Buxton nourishment project experience . The County’s main goal in implementing the Avon
nourishment project is to meet the following objectives:
 Provide a wider beach and buffer storm waves along a critically ero ding section of
Hatteras Island
 Reduce the frequency of storm damages to North Carolina Highway 12 (NC 12) and
existing community infrastructure
 Replace erosion losses and augment the regional supp ly of beach sand by using a
non-littoral borrow source of compatible sedimen ts from an offshore borrow area
 Provide a higher level of storm protection
 Provide a wider recreational beach and create mor e habitat for wildlife
 Integrate a dune management plan into the nourishment design
The proposed project would be consistent with federal and state regulations for construction activities in
the coastal zone, specifically the beach ar ea, and would seek to minimize the impact on marine and
wildlife species during construction. It would be funded by Dare County and property owners within the
Village of Avon .

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Screening Criteria were used to evaluate alternatives for the proposed nourishm ent project. These were
geologic processes, shoreline and barrier island processes, and beach nourishment implementation
options.
5.1.1 Geologic Processes
The applicant recognizes that present-day geologic and coastal processes are integral to the natural
shoreline system in which the Avon project area is located, making it subject to the effects of wind, tides,
waves, and storms. Having sought solutions to erosion on its beach since the 19 70s, Dare County
(applicant) is committed to preserving the b each for the protection of the NC Highway 12, conservation of
its sediments and related coastal resources, and for the enjoyment and benefit of the citizens and visitors
to Hatteras Island . For this reason, the applicant supports a soft-engineering solution like the 2017–2018
Buxton project that is designed to work with nature, using scientifically collected and analyzed field data
to support its plan. The applicant has determined that maintaining a stable beach on an ongoing basis
over many years is presently the most responsible approach to balancing the welfare of the community
with the protection of geologic processes. Beach nourishment, when performed properly with similar
sediments, adds volume and dimension to the beach zone, providing an addition al buffer to absorb the
energy that builds barrier islands.
5.1.2 Shoreline and Barrier Island Geomorphology
Barrier islands are formed and shaped by waves, tidal currents, and winds. At geologic time scales of
greater than thousand s of years, they are ephemeral, temporary landforms dependent on the available
sediment supply and specific position of sea level (Hayes 1994). At decadal to century time scales (time
scales relevant for community planning), barr ier islands exhibit a continuum of shoreline ch anges ranging
from high erosion to high accretion. The majority of US East Coast barrier islands are changing at <1 meter
per year at century time scales (Dolan et al 1990).
Permanent infrastructu re is not possible at geologic time scales on barr ier isla nds or over much of the
coastal plain, but it has been essential for some coastal islands at century time scales. Barrier-island
development has been a critical driver of the tourism economy in the US (Houston 1995, 2002, 2013 ).
Fortunately, not all barrier islands are developed and a large percentage (>50 percent) of the ocean coasts
of Virginia, North Carolina , and South Carolina remain undeveloped , mostly as wildlife preserves .
The development of alternatives took into account the fact that relocation of existing development and
community infrastructure is not possible by the applicant for a number of legal and socio-economic
reasons:
1. A limited right-of-way has been established through easement agreements for location s of
infrastructure.
2. Hatteras Island within historic villages outside the National Seashore boundaries is heavily
developed, and there is little landmass in the Outer Banks to which to retreat.

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3. In 2013, there were 8,572 real-estate parcels valued at approximately $2.1 billion on Hatteras
Island (Lane 2013) and few undeveloped parcels zoned for development, meaning a
tremendous upheaval to the economy, lifestyle, and property values if relocation were
pursued. Property taxes totaled more than $9 million per year to Dare County. Occupancy
receipts totaled approximately $106 million in 2011, despite a two -month closure of road
access on NC 12 between August 27 and the end of October, due to Hurricane Irene. The
occupancy tax earned $2.1 million for Dare County.
4. Relocation or abandonment would likely generate intense public opposition.
5. For a well-established, historic community, nourishment presently provides a relatively cost-
effective means of protecting property, maintaining the shoreline position, and preserving the
local tax base (L Montgomery, www.news-record.com/opinion/columns/07/07/14/the -rising-
tide). The cost of property abandonment would be many times greater than the cost of
nourishment over the next several decades (factoring in multiple renourishments every five
years or so) (USACE 2010).
Avon, Buxton, Frisco, and Hatteras Village contain over 50 percent of the real-estate parcels on Hatteras
Island and, therefore, a large percentage of the property tax base is concentrated near Cape Hatteras .
Island property values declined duri ng the 2008 national recession from upward of $3 billion around 2005,
but rebounded as the overall economy improve d (Lane 2013, Hranicka 2020). The extended closure of NC
12 due to storms produces a ripple effect through the economy, including substantia l lost tourism
revenues and taxes. Repeated closures at an increasing frequency would compound the problem and
potentially undermine property values and the property tax base in addition to jeopardizing many of the
businesses on the island.
Tourism is estimated to account for at least 11,260 jobs in Dare County (Lane 2013) with 2,618 jobs
(~23.2 percent) on Hatteras Island. These jobs represent an estimated payroll of $41 million which adds
to the total state and local taxes generated. The Hatteras Island t ourism economy contributed $10.3
million to the state and $9.4 million to local taxes in 2011.
NC 12 has been damaged by erosion and breaches of the primary dune numerous times since it was
built. According to NC Department of Transportation records (NCDOT 2015, J. Jennings, District
Engineer, August 2014), the segment of road between Oregon Inlet and Hatteras Village has required
over $104 million for maintenance and repairs between 2003 and 2013. Repairs have been most
extensive in the Pea Isla nd section between Oregon Inlet and Rodanthe. The Buxton 2017–2018 Action
Area also required dune rebuilding, road resurfacing, and related maintenance. Assuming the Buxton
section of NC 12 only represents 10 percent of NCDOT expenditures, it equates to approximately $1
million per year.
The Applicant has a fixed budget for the Proposed Action which is expected to provide benefits in the form
of a wider beach and better protection to Avon Village and NC 12 for a variable number of years depending
on which alternative is implemented. Nourishment sand placed along the Avon oceanfront is most likely

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to erode over time and shift downcoast to the Seashore area between Avon and Buxton, thus augmenting
the sand supply in that vulnerable section. There would be indirect and d irect costs to the Applicant under
each alternative.
The “Preferred Alternative” selected for analysis is expected to mimic natural processes and ha ve a negli-
gible effect on coastal processes and endangered and threatened species. It is expected to restore and
widen the beach and protect existing property during storm events.
5.1.3 Beach Nourishment Implementation Options
The applicant will use experience and survey results from the 201 7–2018 Buxton beach restoration project
to guide decisions regardin g beach nourishment implementation options for the proposed Avon
nourishment project. Beach nourishment—the addition of beach-quality sand to the littoral zone from
non-littoral sources (Fig 5.1) (NRC 1995)—can be accomplished by a number of methods , including truck
hauling and dredging via cutterhead dredge or trailing-arm hopper dredge. Cost is generally a function of
the distance between the borrow source and the placement area and the means of conveyance. Therefore,
nearby sand sources are favored for economic reasons.
Experience from t he 2017–2018 Buxton nourishment project is instructive when considering alternatives
for nearby Avon nourish ment. The project involved excavations of quality sand via hopper and
hydraulic dredges from an offshore borrow area. Over 2.6 million cubic yards of sand were added to
the beach, widening it by an average of ~150 ft. Work was accomplished with associated
environmental protection measures over an eight-month period (June—February). During
construction, the project was impacted by four named hurricanes (Irma, Jose, Katia, and Maria)
(September 2017 ) and several northeast storms. During the first two years after project completion,
hurricanes Florence (September 2018) and Dorian (September 2019) impacted the project area with
large waves but negligible dama ge to property and community infrastructure . In addition to
protecting NC Highway 12 and restoring a recreational beach, the 2017–2018 project helped preserve
property values and the local tax base .

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Summer dredging was permitted for the 2017 –2018 Buxton project because of hazardous wave
conditions in the winter months. The Contractor (Weeks Marine) elected to use a cutterhead dredge
(CR McCaskill) to start the nourishment on 21 June 2017 which was over one month later than originally
planned due to equipment delays on another project (C Brousard, Weeks Marine, pers comm June
2017). Production of construction lagged due primarily to rough sea conditions in July and August that
frequently curtailed operations and led to mechanical breakdowns. As of 22 August 2017, ~1.1 million cy of
sand (~42 percent of the total contract volume) was placed on the beach by the cutterhead dredge.
In September 2017, four named hurricanes (Irma, Jose, Katia, and Maria) impacted the project area and wave
heights were significantly higher than the required safe operati ng conditions for a cutterhead dredge.
Construction had to cease for over 50 days until 11 Oct when the Contractor started to use a hopper dredge
(RN Weeks). During each work shutdown, the dredge had to return to a safe harbor over 100 miles away in
Norfolk (VA). Despite the intermittent work schedule, construction moved forward. As of 22 December
2017, nourishment in front of the narrow isthmus of NC Highway 12 was completed, and the highly
vulnerable section of the road was protected.
FIGURE 5.1. Idealized initial nourishment profile for sand placement seaward of the foredune and upper beach. Upon project
completion, storm waves and winds quickly shift some nourishment sand toward the dune, as well as into deeper water. The
resulting “equilibrated” profile would exhibit a narrower berm (i e – “dry sand beach”) as illustrated. Note the initial constructed
profile (berm width) would vary between ~60 ft and 150 ft according to the specific sand deficit and erosion rate at a particular
segment of beach. The area of intertidal wet sand is expected to remain constant, but be displaced seaward after initial
equilibration of the nourishment sand. In some areas, extra sand will be placed and shaped into a protective dune seaward of
existing vegetation lines to accelerate dune formation. An active program of sand fencing and vegetation will be implemented
along the oceanfront to maintain as much of the nourishment sand as possible on the active beach while minimizing sand
encroachment on existing structures.

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Weeks Marine’s newly constructed hopper dredge, Magdalen, passed the sea trials and obtained the
operation certificate in January 2018 , in time to complete the final ~20 percent of the project. With twice
the capacity of RN Weeks, the Magdalen finished the last ~0.5 million cy of work and delivered her last load
at 1:30 pm on 27 February 2018, almost 5 months later than the Contractor’s original estimate.
Despite all the delays, the project was completed without any sea -turtle takes or other environmental
incidents. Collaborations among the Owner (Dare County), regulatory agencies (USACE, NPS, and NCDEQ),
and the Contractor remained excellent during the course of construction. The newly nourished beach has
withstood a series of nor’easters in March 2018 and 2019 without closure of NC Highway 12 or damage to
Buxton oceanfront properties. If summer dredging had not been permitted, the duration of construction
would have been even longer and the road could have breached again during nor’easters.
During the first three years after completion, the 2017–2018 nourishment project had lost more sand
than expected with annual losses through August 2020 averaging ~650,000–700,000 cy/yr. The main
reasons are likely as follows.
 Shoreline offset at the existing groins which accelerates erosion at the south end of the project
 Normal nourishment sand spreading at the project boundaries (ie – End Loss)
 Four named hurric anes impacting the project area in September 2017 during construction
 A series of nor’easters impacting the project area in March 2018 after project completion
 Recent hurricanes Florence and Dorian impact
 Sand shifted offshore beyond −24 ft NAVD and downcoast due to the existence of a deep trough
between the beach and outer bar
 Deterioration of the groins at the south end of the project
In preparing this EA for the proposed Avon beach nourishment project, the applicant considered alternate
borrow sources, c onstruction methods, and placement configurations. This EA addresses methods and
sources deemed feasible and most advantageous with respect to project longevi ty and environmental
protection given a fixed construction budget established by the applicant. Beach nourishment
performance and longevity are highly dependent on sediment quality and project length (NRC 1995, Dean
2002). Accordingly, certain construction methods and sand sources were eliminated from further
consideration as discussed later in thi s section. While the performance of the Buxton project was
compromised by a higher -than-normal frequency of storms during and soon after construction, the setting
differs from Avon in several respects. Avon is experiencing accelerated erosion along a lim ited section of
beach which is flanked by more stable sections of the Seashore. Buxton has an unstable morphology that
is dependent on groins to hold a salient (“bulge”) in the shoreline around the old lighthouse site. This
salient accelerates currents inside the outer bar and accounts for the deep trough that draws off sand at a
rapid rate. The Avon nourishment will produce less of an obtrusion of the shoreline in the area
experiencing the greatest sand deficit south of Avon Pier . This is expected to leave a more stable
“planform” (ie – straighter shoreline) with respect to the adjacent healthy sections of beach.

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5.2 Description of Alternatives
Three alternatives are considered for detailed analysis—the “No-Action Alternative” and the two action
alternatives. Off-site and on-site alternatives dismissed for analysis are also discussed in this section.
 Alternative 1 –No-Action
 Alternative 2 –Beach Nourishment with Winter Construction
 Alternative 3 (Preferred Alternative)–Beach Nourishment with Summer Construction
5.2.1 ALTERNATIVE 1–NO-ACTION
Under the “No-Action Alternative,” the US Army Corps of Engineers and National Park Service would not
issue permits to Dare County for beach nourishment along the shoreline in Cape Hatteras National
Seashore and the Village of Avon Beach.
The No-Action Alternative provides a basis for comparing management direction and environmental
consequences of the action alternatives. Should the No -Action Alternative be selected, Dare County,
the State of North Carolina, and local entities would respond to future maintenance needs associated
with the current natural conditions of unabated erosion in the Buxton Action Area. Current responses
to that erosion by the NC Department of Transportation would continue, including sand scraping and
road repairs. As erosion progresses and sufficient room to maintain a protective dune no longer exists,
the state and individual property owners are likely to implement short -term emergency measures such
as sand-bagging. This alternative assumes that a high potential exists for NC 12 to be closed due to
major storm damage and that NCDOT would carry out repairs as needed to reopen the road. Possible
emergency repair options to reopen the road would include a temporary bridge or emergency beach
nourishment, as were completed in 2012 at the Pea Island breach and in 2014 north of Rodanthe.
NCDOT (2015) evaluated various alternatives for realigning or bridging sections of NC 12 between Avon
and Buxton.
If a breach occurred as feared during a major storm(s), Hatteras communities, as in the past, could be
isolated from the mainland until the road was reopened. Emergency services would have to seek
alternative ways of transporting sick or injured people off the island until repairs could be made. The
normal transport of food and goods for families and materials to repair damaged houses and businesses
would be interrupted. Other than helicopter lifts and boat traffic, travel would cease , and transporting of
goods and services would likely occur by ferry or small plane.
Furthermore, under the “No Action Alternative,” Dare County would not be eligible for FEMA funds to
restore an “engineered beach nourishment,” an important incentive for local communities like Avon.
Maintenance of beaches by nourishment r educes property damage claims and thereby reduces federal
outlays under FEMA flood insurance policies following major storms (FEMA 2020).

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5.2.2 ALTERNATIVE 2–BEACH NOURISHMENT WITH WINTER CONSTRUCTION
Alternative 2 –Winter Construction consists of beach n ourishment in the wintertime via dredge using an
offshore borrow area and placement along ~1 3,200 linear feet of shoreline along Cape Hatteras
National Seashore and the Village of Avon; ie the Avon Action Area (see Fig 1.2). Alternative 2–Winter
Construction requires contracting with a professional dredging company experienced and equipped to
conduct a project of this type and scale. The specific design, plans, and specifications of the
nourishment project on which dredging companies would provide bids for construction would be
prepared by the Applicant’s consultant, a registered engineering firm with demonstrated experience in
these types of projects. If permitted, the Applicant, its consulting engineer, and the dredging company
would coordinate the work closely with representatives of the US Army Corps of Engineers and the
National Park Service to ensure the project complies with federal and state permits for construction.
Beach nourishment by dredge involves hydraulic excavations of a borr ow area, pumping via pipeline,
and discharge of a sediment -water slurry along the beach. Water drains, leaving the sediment in place
to be shaped by land-based equipment such as bulldozers. A nourished beach is typically constructed
in sections, adding sand to the active beach zone working parallel to shore. Bulldozers distribute the
sand from the pumpout point to elevations and slopes typical of a natural beach (Dean 2002). Surveys
before and after sand placement are used to confirm how much sand has been added in each section
and whether the elevation and slope of the new beach conform with the plans and specifications for
the project which reflect the approved profiles in the permits.
Alternative 2 –Winter Construction would involve excavation of sand by o cean-certified dredges from a
borrow area ~2 miles east of Avon Pier (see Fig 1.2). The dredges would be either cutter head dredges
or self-propelled hopper dredges. If traditional suction cutter head dredges are used, excavations
would be limited to ~10 feet below the substrate and would be pumped directly onto the beach via a
submerged pipeline. Sections of pipe (typically 40 feet long) would be added as construction
progressed along the beach. Approximately 200 –300 feet of beach would be nourished over a 24-hour
period, working from one of two landing points for the submerged pipeline. The landward limit of sand
placement would be seaward of the foredune along the existing dry -beach area. Initially, the material
would be shaped to form a gently sloping be rm at or below the normal dry-beach level in the Action
Area. The seaward edge of the nourishment would be sloped by dozers to match a typical beach slope
in the swash zone, the area over which waves break and run up the shore. After project completion, th e
nourished profile would generally adjust to waves.
If hopper dredges are used, excavation depths would be shallower, but would not exceed ~10 feet in
the aggregate (after multiple passes) within the designated borrow Area. Hopper dredges tend to leave
some undisturbed areas. Hopper dredges are self-propelled vessels that pump sand into the hopper of
the ship then motor to a pumpout point where a length of submerged pipe extends ~1,500 feet offshore
from the beach. Sand in the hopper is pumped to shore and distributed by the same methods used for
cutter head dredge discharges. The environmental impacts of such cutter head and hopper dredges are
essentially the same on the beach, but vary at the borrow area as discussed later.

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Using either type of dredge, excavations would be restricted to the approved offshore borrow area and
would avoid cultural resources, shipwreck debris, or obstructions that may be present. Further, the
borrow area would be chosen based on having sand that closely matches the existing sa nd in the Action
Area. Along the beach, no sand would be placed on the foredune or private property. Upon completion,
the nourished beach would be left to equilibrate under wave action —that is, even out and develop a
profile and slopes typical of a natura l beach.
Normal safe operations require dredging equipment and personnel to move to a safe harbor before a
storm event occurs. Operations can only resume after seas return to operational conditions.
Due to the sailing time from the Proposed Action Area to the nearest safe harbor in the Norfolk, Virginia,
area, each northeast storm event is likely to suspend dredging operations for a minimum of three days.
Based on average storm frequencies of 1 per 6 days during winter months in the Action Area, dredging
efficiency is expected to be <50 percent for either hopper or suction cutter head dredges. When
common winter storms pass through the Avon area, pipe on the beach may have to be removed
temporarily and stored on high ground.
The scale and scope of Alternati ve 2–Winter Construction would be dependent on the number of
operational days that are possible in the Action Area within the assumed four-month window for
construction. Winter construction would be limited to those days when waves are less than the
threshold for safe operating conditions (Fig 5.2). Factors to consider are the average frequency of
nor’easters and tropical storms (1 per 6 days) (USACE 2010), projections of efficiencies for winter
dredging in the northern Outer Banks (USACE 2000, 2010), and e xperience within similar settings (CSE
2012, 2014). Under Alternative 2–Winter Construction, construction would be limited to 2–3 days per
week of 24-hour operations pumping sand, interrupted by moving the dredge(s) to a safe harbor during
storm forecasts .
The scale, scope, and construction duration for Alternative 2–Winter Construction is based on a fixed
budget established by the Applicant. Based on preliminary planning and design, and the assumptions of
dredging efficiency and unit costs, Alternative 2–Winter Construction would limit the excavation and
placement of volumes to roughly half that of the Preferred Alternative (ie – ~500,000 cy). This equates to
a maximum average fill density of ~40 cubic yards per foot along 13,200 linear feet. It can be shown that
a fill density of this magnitude equates to a maximum average beach width increase of ~35 feet in this
setting (Overton and Fisher 2005, Kana et al 2015). It would take 30 dredging days averaging 20,000 cubic
yards per dredge per day to accomplish the work. At <30 percent production efficiency, more than a three-
month construction duration would likely be required if only a single, ocean-certified dredge is used.
The total nourishment volume that would be accomplished under Alternative 2 –Winter Construction
would not provide enough volume to accomplish the purpose and goals of the proposed project.
Alternative 2–Winter Construction would require a staging area for mobilization of equipment and
temporary storage of shore pipe, which are typical ly 40-foot lengths of 30-inch-diameter steel pipe. As
beach building occurs, the equipment and pipe would be stored on the newly constructed beach and

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would move with the active work area. For the Avon Action Area, two landing points are likely to be
used. One would be just north of Avon Pier and the other would be positioned ~7,000–8,000 ft south of
the pier. Pumping onto the beach would begin at these landing points and proceed northerly or
southerly for up to ~4,000 feet, adding shore pipe as the beach is built. Upon completion of a ~3,500–
4,000-foot section of the project, pipe would be removed and shifted to the next work area, proceeding
in the other direction from the landing point. At any point in time, there would be between ~100 feet
and up to 4,000 feet of beach impacted by the presence of the pipeline.

The active beach pumping area would extend ~300 feet alongshore on a given day. Pipe -loading
equipment, support vehicles, fuel barge, and a portable office and shelter for workers would move with
the active work zone and would be cordoned off from the public. The active work area would be marked
by flagging ribbon and would be limited to hard -hat personnel who have completed safety briefings.
Dredge safety personnel would be statio ned at the safety fence to prevent unauthorized entry and
safeguard the public from areas where heavy equipment is operating. Upon completion of
construction, all equipment and supplies would be removed from the site. The beach would be graded
to eliminate tire tracks, depressions, and mounds. The staging area(s) would be restored to pre -project
conditions. If compaction measurements show values above USFWS thresholds after project
Figure 5.2. Graph showing the monthly average wave climate from 2003 –2020 at NDBC Wave Buoy Station 41025 at Diamond
Shoals (NC) near Avon and Buxton compared with the wave climate at the USACE Field Research Facility at Duck (NC). The crit eria
for safe dredging apply to hopper -dredge operations using ocean-certified equipment per informal guidance by dredging
contractors. Suction-cutterhead dredges generally cannot operate safely in waves >3 feet (USACE 2010). The graph shows that
average monthly wave height exceeds 5 feet from September to April in the Proposed Action Area. Calmest conditions occur in
June and July when average wave heights are less than four feet. (Source: NDBC)

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completion, the Applicant would seek guidance on whether tilling of the beach should be performed
and implement tilling at the direction of state and federal resource agencies.
Work under Alternative 2–Winter Construction would be completed during winter months within particular
environmental windows for construction prescribed by the permits. The previous window for hopper
dredging under the 1997 South Atlantic Regional Opinion (SARBO) is December 1 through March 31 (NMFS
1997). The 2020 SARBO does not specify a limited window for hopper dredging due to sea turtle presence
and also considers impacts to other species such as migration periods for whales. Based on this more
recent biological opinion, there can be benefits as well as negative consequences of hopper dredging
during any month which must be considered in the planning for any offshore dredging. The applicant
recognizes the potential for impacts and accordingly plans to implement the mitigation and monitoring
required to minimize impacts, including use of endangered species observers (ESO) on board the dredges
(see Appendix B). The location of the Action Area is about 105 miles from the nearest safe harbor that can
accommodate large ocean-certified dredges. Oregon Inlet (~30 miles from the Proposed Action Area) is
too shallow for entry by large hopper dredges (typical draft unloaded is ~15 ft).
Further, recent nourishment projects along the northern Outer Banks have proven that offshore
dredging is best conducted during the summer season , the only time of year when average waves are
lower than safe operating conditions for the present fleet of ocean -going dredges. These projects
include the initial 2011 Nags Head nourishment project, followed by Rodanthe in 2014 (USACE 2013),
and five major projects in 2017, including Duck, Kitty Hawk, Kill Devil Hills, Buxton/NC Highway 12—
Cape Hatteras National Seashore , and Nags Head beach renourishment in May -August 2019. Given the
highly dynamic and storm-prone coast, calmer and more temperate condi tions help to ensure the
safety and efficiency of these construction projects. For these reasons, “Beach Nourishment with
Summer Construction” is presented in this EA as the preferred alternative.
5.2.3 PREFERRED ALTERNATIVE 3 – SUMMER CONSTRUCTION
Alternative 3 – Summer Construction consists of beach nourishment during summer months via dredge
using an offshore borrow area and placement along up to 1 3,200 linear feet of shoreline along Cape
Hatteras National Seashore and the Village of Avon (ie, the Avon Action Area) (see Fig 1.1). It differs from
Alternative 2–Winter Construction in terms of the amount of sand placed and the season of
construction. Sand excavation and placement would be as described under Alternative 2 –Winter
Construction. However, the project would be constructed during fair -weather months in summer when
dredging efficiency can be maximized in the Action Area.
Under a fixed budget established by the Applicant, Alternative 3 – Summer Construction would provide
up to twice as much volume for the given budget as Alternative 2. Preliminary design calls for the addition
of up to ~1.0 million cy for purposes of replacing eroded sand and providing “advance nourishment” for
certain future losses. This quantity of nourishment sand would widen the beach by ~60 feet after normal
adjustment of the profile (see Fig 2.1). The higher volume (approximately twice that of Alternative 2–
Winter Construction) would provide 3–5 years of erosion relief based on the analysis of erosion (See
Appendix D). The additional sand would increase project longevity to ~5 years along significant portions

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of the project length before the beach returned to a deficit condition. Alternative 3 provides up to ~1.0
million cubic yards to erode under normal yearly processes (annual loss rates in the range ~200,000 cubic
yards per year, which is significantly higher than the long-term historical loss rate determined for the
Action Area. Appendix D evaluates erosion along Avon in detail and presents the results based on best
available data ~140,000 cy/yr over the project length. Note that this result accounts for the high gradient
in erosion between the center of the project and each end. Given the uncertainty of storm intensity and
erosion rates after the project, this additional volume (relative to Alternative 2) is critical for meeting the
goals and objectives of Dare County.
Alternative 3 – Summer Construction would be performed by trailing arm suction hopper dredges or
traditional hydraulic cutterhead dredges with booster pumps. The dredges would reach from the
borrow area to the furthes t segment of the project beach, a distance of ~1 5,000 linear feet. (The two
dredge types were generally described under Alternative 2 –Winter Construction.) The Applicant desires
permits which allow both hopper and hydraulic dredges to be used at the discre tion of the dredging
contractor. Allowing both types provides the most flexibility to accomplish the work in the shortest
time. It also allows the contractor to use the resources it determines to be the most advantageous to
minimize the environmental risks and maximize dredging efficiency. One or more hopper dredges and
a hydraulic dredge may work on the project at the same time. The objective is to complete the project
in one season and in the shortest time possible.
As a result of prior correspondence fro m the Dredging Contractors of America (USACE 2010) and
discussions with qualified dredging contractors, the Applicant has concluded that the Proposed Action
could not be accomplished safely or cost -effectively during fall or winter in the Avon Area by either
cutterhead or hopper dredges. In the summer, cutterhead dredges are less preferred, because offshore
mean wave heights exceed threshold conditions for that type of dredge (Fig 5.2, also Appendix D –
Littoral Processes ). The use of hopper dredges in the summer, with the cutterhead as an option during
calmer seas, is the Applicant’s preferred approach to ensure the Proposed Action is completed.
The Proposed Action involves dredging and placement of up to ~1.0 million cubic yards on the target
beach. The average production per day varies according to sailing distance from the borrow area to the
beach, as well as weather and environmental restrictions placed on the project. Based on project
experience at Nags Head (CSE 2012), one hopper dredge can excavate and place from 15,000 to 30,000
cubic yards per day (24 -hour period). Under ideal conditions, a hydraulic dredge can excavate up to
60,000 cubic yards per day. That volume would decrease with increased wave heights and work
stoppages as well as relocation due to severe weather. Therefore, project duration is dependent on
average daily production.
A single hopper dredge operating at an efficiency of 60 percent and a daily production of 20,000 cubic
yards per day would require 85 calendar days (~3 months) to complete the project. Efficiency is
measured as the actual dredging time divided by the total time available. Giving the contractor flexibility
to use both hopper and hydraulic dredges, with an average (net) production of 30,000 cubic yards per
day, the project would require 33 days (~1 month) to complete. Net production at Nags Head for the 2011
project was ~42,000 cubic yards per day with two dredges, one hopper dre dge and one suction

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cutterhead dredge, operating May 27 to August 27. Net production dropped to ~13,000 cubic yards per
day between August 27 and October 27 with two smaller hopper dredges operating (CSE 2012). The
downtime associated with shutdown and redeployment of the dredges during weather events is the
main factor contributing to the efficiency and construction duration of the Proposed Action.
May to August is a period of relative calm compared to fall and winter months (September to March) in
the Proposed Action Area. Permitting the dredges to work over the warm and calm weather months
(May to August), along with allowing both hopper and hydraulic dredges, would mitigate some of the
risks to personnel and equipment and would provide conditions where the work could be completed in
a much shorter time period, thus reducing the duration of environmental impacts. The production
efficiencies for Nags Head (2011) was close to 80 percent from June through August, a rate that
incorporates downtime due to Hurricane Irene and other weather events (CSE 2012). Projections of
dredging efficiency under Alternative 3 take into account the possibility of hurricanes and other high
wave events during summer in the Action Area. Equipment requirements and operations under
Alternative 3–Summer Construction would be the same as Alternative 2 –Winter Construction.
However, work during summer months, when threatened or endangered species may be present,
would require modification of operations as follows:
1) Endangered species observers would be stationed on dredges to alert dredging personnel
and record encounters. This would include authority to suspend operations while wildlife
resources officials are contacted in the event of a take as defined under the Biological
Opinion applicable for the Proposed Action .
2) Certified trawlers would be retained to trawl for sea tu rtles ahead of operating hopper
dredges and relocate turtles if encountered, or operate as non -capture trawling pe r final
recommendations of NMFS.
3) Continuous nightly beach patrols would be performed by certified monitors to locate any
turtles that are stra nded behind the dredge pipe on the beach and relocate them to the
waters’ edge or deal with them according to directives by and in consultation with USFWS
and North Carolina Wildlife Resources Commission (NCWRC).
4) Vehicle ingress and egress at night would be escorted by certified, endangered species observers.
5) Lighting at the Action Work Area on the beach would be minimized in conformance with
USFWS requireme nts for beach lighting.
6) The use of bulldozers at night would be reduced to the minimum required for s afe
operations as sand is being discharged.
7) The order of work (sections to be filled) would be accomplished in close coordination with
NPS officials so that there would be the least practicable disruption to bird -nesting
activities along Seashore lands .
8) No-work buffers along the beach would be established around the turtle or bird nests in
coordination with USFWS, NCWRC, and NPS officials
Other operations modifications as may be recommended by federal and state resource agencies.

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5.3 ALTERNATIVES ELIMINATED FROM FURTHER STUDY
Several alternatives were identified during the Avon planning process based on experience with the
nearby Buxton project (USACE-DOI-NPS 2015). Some of these alternatives were determined to have
unacceptable impacts or to be technically or economically infeasible. Other alternatives identified were
determined to be outside the project purpose, not allowed under existing North Carolina laws, or
beyond the means of the Applicant.
The following alternatives eliminated from further study are presented in several categories:
1. Alternate nourishment borrow sources,
2. Erosion control methods designed to retain sand, and
3. Shore-protection methods involving hard structures.
5.3.1 Rationale for Dismissing Nourishment Using Non -Offshore Sand Sources
Based on previous practice along the US East Coast, the following classes of borrow sources have been
used for beach nourishment (CERC 1984):
– Lagoon sediments – Offshore deposits – Inland deposits
– Inlet shoals – Recycled spoil sediments – Freshwater pond deposits
– Nearshore bars – Accreting spits/beach deposits – Imported material
In general, economics favors the borrow source(s) that matches the native beach quality, involves the
shortest transportation distance, and min imizes environmental impacts. Large-scale projects, such as
the Avon nourishment project, require large volumes of material that may not be available in only one
offshore deposit or alternate borrow source .
The following sediment sources are considered unacceptable for the Pro posed Action.
Lagoon Deposits in Pamlico Sound – Generally, sand in the sound is much finer than sand on the beach
and contains levels of mud and silt unacceptable for beach nourishment. Additionally, the environmental
impacts of a large-scale dredging project (up to ~1.0 million cubic yards) in Pamlico Sound would be high
because of the greater diversity of estuarine organisms and submerged vegetation present. I n a US
Geological Survey (USGS) paper written in cooperation with the National Park Service, Dolan and Lins
(1986) discussed the use of beach nourishment for shoreline stabilization, stating:
… artificial beach nourishment … has long been considered the most desirable method of protection
because (1) placement of sand on a beach does not alter the su itability of the system for recreation, (2)
nourishment cannot adversely affect areas beyond the problem area, and (3) if the design fails, the effects
… are soon dissipated.
Perhaps the greatest disadvantage of artificial nourishment is that great quantit ies of sand of suitable
quality (type and size) are not readily available. In the past, sand was dredged from sounds and bays
immediately inland from the beach or transported from inland sources. Because of recent concern about
estuarine ecology, however, and because materials dredged from sounds and bays are generally too fine
to be effective in beach nourishment, estuarine and bay sources have been less desirable and are no longer
readily available. The only future source of large quantities of sand for n ourishment of the Outer Banks
appears to be offshore areas, such as Diamond Shoals and coastal inlets [Dolan and Lins (1986), pg 34].

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Inlet Shoals (Inshore) — Significant accumulations of sand occur in the ebb - and flood-tidal delta
shoals of Oregon Inlet ~30 miles north of the project site. The mean grain size of these deposits tends
to be much finer than native beach sand (USACE 2010). The flood shoals are located inshore of the
Oregon Inlet bridge and would have to be pumped either directly to the projec t site with the aid of many
booster pumps or pumped offshore to hopper dredges which could transfer and pump out the material
after sailing nearly 70 miles (roundtrip) to the project site. Additionally, these ephemeral flood -tidal
delta shoals are habitat for a number of protected shorebird species. The environmental consequences,
level of coordination required, the potential for disapproval by conservation groups and regulatory
agencies, the cost implications due to pumping distances, and the unsuitable se diment size make this
source of sand infeasible when compared to the offshore borrow sources.
Significant deposits of sand are available from the ebb -tidal delta shoals of Oregon Inlet. The navigation
channel across the outer bar is dredged frequently by t he USACE. Typically, the dredged material is
disposed of on the beaches at the northern tip of Pea Island adjacent to Oregon Inlet. CSE (2011)
determined the location of the placement of the dredge spoil, sampled the material, and analyzed the
sand samples for texture and suitability for beach nourishment. The material from Oregon Inlet is
generally fine -grained sand (<0.25 millimeter mean diameter) and much finer than native beach sand
along Nags Head (USACE 2010). The Avon beach sand is similar in size distribution to Nags Head (CSE
2013) (Appendix A - Geotechnical Data). It can be shown that placement of finer sand on a beach
typically leads to rapid dispersal into the underwater part of the beach zone (Dean 2002). This lessens
the benefit of nourishment (narrower dry-sand beach) and reduces wave attenuation relative to
sediment sizes that match the visible beach.
Nearshore Bar(s) Along the Project Area — Sand stored in nearshore bars (water depths <20 ft) is part
of the active beach profile and is an impo rtant component in the beach system that provides wave
dissipation. Access to the material would be difficult by deep -draft hopper dredges. Additionally, the
material in longshore bars is generally too fine for retention on the dry beach and is inappropria te for
beach nourishment. Grain size data for samples in the Avon Action Area support this finding (see
Appendix A – Geotechnical Data).
Accreting Spits/Beach Deposits — Major deposits of beach sand are accumulating on Cape Point
within Seashore jurisdiction (Fig 5.3). Excavation of these deposits would involve significantly more
environmental consequences than offshore deposits because Cape Point is designated as critical
habitat for the piping plover.
Inland Deposits — Material imported from sand mines in Currituck County (~7 0 miles from Avon) was
used for building dunes in Nags Head and Kitty Hawk after Hurricane Isabel. Use of distant sand mines
would be cost-prohibitive, based on trucking costs for much shorter haul distances between Currituck
spit and Kitty Hawk (~16 miles). Dune-building projects at Nags Head and Kitty Hawk were $16.00 per
cubic yard and $15.15 per cubic yard (respectively) in 2005 following Hurricane Isabel (CSE 2005a). This
represents nearly twice the unit costs of nearby offshore b orrow areas (including pumping and
mobilization and demobilization costs). Under a fixed budget established by the Applicant, a doubling

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of transportation costs would result in a major reduction in the total project volume, which would
reduce the project longevity and would not accomplish the goals and objectives of the Applicant.
CSE (2020) evaluated an inland source within the Village of Avon (Hollowell property and sand pit) and
spoil from channel maintenance dredging into Avon Harbor (Figure 5.4) (CSE 2020). Both
deposits/sources were determined to be suboptimal for the proposed project because:
1) Finer sediment grain size (ie – much more volume would be required to produce comparable
performance as the proposed offshore borrow area), or
2) The volumes available would not be sufficient to meet the target nourishment volume specified
in the plan, or
3) Excavations and transfer to the beach would involve more time, disruption to tourism, and
damage to community infrastructure (eg – damage to roads).

Figure 5.3. Oblique aerial photos of Cape Point, a highly accretional cuspate foreland which accumulates sediment eroded from
the east and south Buxton oceanfront’s. Cape Point is an important habitat for endangered and threatened species, such as the
piping plover. The left image is looking north with Cape P oint in the foreground and the Village of Buxton along the top. The right
image is looking west across the Cape Point foreland with the east -facing beach along the lower edge of the picture and the broad
south-facing beach arcing toward the top left corner of the picture. [Images by CSE on 10 September 2014]

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Figure 5.4. Potential borrow sources considered for the Avon nourishment project (CSE 2020).

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Freshwater Pond Deposits — No known freshwater ponds are nearby that require maintenance
excavations, or that could provide the quantities of beach -compatible sediment required for the
Proposed Action.
Recycled Spoil Sedime nts — Avon Harbor dredge spoil material was considered but rejected for the
present project because of the limited volume available and the less compatible grain size .
Primarily for reasons of sediment quality, environmental impacts, economics, or unavail ability within
economic transportation distances, the alternative borrow sources discussed herein are not deemed
acceptable for the Avon beach nourishment project. The alternative of nourishment using non -
offshore sand sources is not considered for further analysis in this EA.
5.3.2 Rationale for Dismissing Sand-Retaining Structures and Techniques
A number of erosion-control methods can be used to intercept mobile sands in the beach zone. These
include three general types of sand-retaining structures—jetties, groins, and breakwaters —and one
technique—beach dewatering systems. Jetties and groins are shore -perpendicular barriers extending
from the upper beach/toe of dune to some distance offshore. They may be constructed of timber, steel
sheet piles, quarry stone, pre-cast concrete units, or sand bags. In the presence of a predominant trans -
port direction (north to south along the beach in the Action Area), sand tends to accumulate along the
upcoast (north) side of the structure, producing a salient (bulge) in the shoreline related in size to the
length of the structure. When the groin is filled to capacity, excess sand would be transported by waves
around or over the structure to the downcoast (south) shoreline, leaving a salient in place. The beach
along the upcoast side of the groin or jetty would generally be wider than the beach downcoast for
some distance in either direction, which is also a function of groin length (ASCE 1994). Commonly,
observable modification of the shoreline due to the presence of g roins or jetties can be detected 10 –20
times the groin length depending on numerous factors (CERC 1984).
Groins, jetties, and breakwaters are a proven method for reducing sand losses along beaches on the
upcoast side of a structure and have been used pre viously in the Buxton Action Area to protect the US
Navy Facility and Cape Hatteras Lighthouse (Machemehl 1979, NPS 1980, USACE 1996, NPS 2013 a).
Intermittent breakwaters and nourishment have been incorporated into a shore -protection plan for
Colonial National Historical Park in Virginia (NPS 2012 a). Figure 5.5 shows existing groins at the south
end of the proposed Buxton project and their impact on the shoreline near Cape Hatteras Lighthouse.
The groins were constructed in 1969 (Machemehl 1979) and have produced a salient (bulge) in the
shoreline along Buxton Village. The salient results from the groins holding a segment of beach in place
while the beaches north and south of the groins continue to erode.
While groins, jetties, and breakwaters combined with nourishment may reduce sand losses and improve
project longevity, they are not permissible under existing North Carolina CZM rules and regulations.
Groins and jetties are not evaluated further in this EA because they are not allowed along the
northern Outer Banks under present state CZM rules and regulations.

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FIGURE 5.5. Oblique aerial photograph looking north along the Buxton and Avon Action Areas with the moved Cape
Hatteras Lighthouse at the lower left side of the image and the Village of Avon near the top right corner of the image.
White foam lines of breaking waves over the near shore bar parallel the beach. The east -facing shoreline bulges seaward
in the mid dle of the image. This bulge marks the location of three groins fronting the former US Naval Facility and
former location of the Cape Hatteras Lighthouse. The salient (bulge) visible to the north (upper right) is Rodanthe and
Salvo. [Image courtesy of USACE–Wilmington District taken 9 September 2000]

Breakwaters are shore-parallel structures placed close to the beach to modify and reduce wave energy
and sand transport along the coast. In the sheltered lee of breakwaters, sediment falls out of
suspension and accumulates in the form of a salient. In extreme cases, sand would build out to the
breakwater, forming a tombolo spit of high ground between the beach and the structures.
Breakwaters are not evaluated further in this EA because they are not allowed along the North
Carolina coast under present state CZM rules and regulations.
Beach dewatering is a technique for sand retention whereby wave swash is withdrawn by suction
through a system of pipes and vacuum pumps. The water is discharged offshore or in holding ponds for
gradual percolation into the ground. By drawing off part of the swash before it runs back down the
sloping part of the beach, less sand moves in the return flow. The result is the accumulation and
retention of sand in the dry beach zone in the area where pipe is in place. Results are mixed and depend
on many factors (Turner and Leatherman 1997).

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Such a system is not considered viable for the project at Buxton for several reasons:
1) Beach dewatering requires an extensive network of perforated pipe to be buried close to
the surface of the beach —a permanent installation (which would potentially interfere with
turtle nesting activities)
2) The system requires pumps, infrastructure, and discharge points that are not available
3) The sand deficit along the Action Area greatly exceeds the scale of the existing beach
where such a system would be installed
4) Dare County and the Park Service do not wish to install permanent infrastructure (piping)
along high-energy beaches subject to significant seasonal fluc tuations in width and
elevation
5) Beach dewatering does not augment the sand supply in the beach zone, but rather
captures some fraction of sand moving downcoast a t the expense of adjacent areas
Beach dewatering systems are not evalu ated further in this EA because they do not meet the purpose of the
project or they are not allowed under present state CZM rules and regulations.
5.3.3 Rationale for Dismissing Other Potential Alternatives
Other potential alternatives considered and dismissed include:
• Structural shore protection —including seawalls, revetments, and bulkheads
• Structure relocation—including NC 12 realignment
• Structure abandonment
• Alternative transportation system
• Nourishment along other erosion hotspots such as the Hattera s Village reach west of Buxton,
which is narrow and vulnerable to another breach
As previously described, hard erosion-control structures are prohibited under North Carolina CZM rules
and regulations. Installation of a protective seawall along the most vul nerable sections of Avon would
also not meet the purpose and needs of the project.
The Applicant (Dare County) has no authority to move, elevate, or abandon NC 12. Such alternatives
would not meet the purpose and needs of the project.
NCDOT (2015) completed the NC 12 Feasibility Study from Avon to Buxton and outlined possible short -
term (5-year) and long-term (50-year) alternatives for protecting and maintaining Highway NC 12
between Buxton and Avon. The short -term alternatives include A) minor road real ignment (15–65 ft
west of the existing roadway); B) road relocation 100 –180 ft to the west including four bridge spans
(totaling ~600 ft) over areas of poor soils such as fringing salt marsh; and C) beach nourishment along
1.1 miles of shoreline totaling ~642,000 cy (NCDOT 2015, p 28). A fourth short-term alternative (D) would
combine road relocation with nourishment reducing the volume to ~391,000 cy for a 5 -year project.

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The NCDOT (2015) alternatives are based on projections of the average shoreline chang es for the study
area (2–8 feet per year) adjacent to the Avon Action Area over a 45-year time span. Forecast shorelines
are then compared with the seaward edge of pavement to determine whether the NCDOT minimum 230
ft buffer to mean high water is maintai ned under each alternative. Moving the road landward, for
example, would help maintain the separation distance and reduce the volume of nourishment required.
Relocation or abandonment of existing buildings and infrastructure is rejected by the applicant
because it would not meet the purpose and needs of the project. Dare County has no jurisdiction over
existing private structures and cannot remove them under present state law even if they are
condemned by the State. Removal of the oceanfront houses would be exceedingly costly as a result of
(1) the high value of beach resort property, (2) the cost of litigation necessary to force property owners
to abandon homes and businesses if they do not agree to buyouts at market prices, (3) loss of tax
revenue, and (4) loss of rental income and its ripple effect on the local economy.
Property abandonment and relocation associated with ongoing beach erosion are encouraged under
existing state CZM regulations. Considering present property values, the economic costs of pr operty
abandonment are exceedingly high and generally involve extensive litigation, as demonstrated by a
recent case at Nags Head (Sansotta vs Town of Nags Head, US District Court –Eastern District of North
Carolina 2:10–CV–29–D). The Town of Nags Head settled with a property owner around 2015 and agreed
to pay the owner $1.5 million for six houses that had been sitting in the surf zone for nearly ten years
and were rendered uninhabitable. Buyouts and relocation of just 30 -40 houses in the most critically
eroded section of Avon would likely cost $50 -100 million at present market values (Source
www.zillow.com). Such costs greatly exceed the funds available for the proposed Avon nourishment
project, and buyouts would not meet the goals and objectives of the a pplicant.
For reasons stated above and other practical considerations, structural alternatives, structure relocation, and
structure abandonment are eliminated from further study because they do not meet the purpose and needs of
the project, or Dare County has no authority to impose them, or they are not allowed under state law.
5.3.4 Nourishment Construction Alternatives Eliminated from Consideration
In addition to the two nourishment placement alternatives retained for further analysis (previous
section of EA), four alternative placement methods were considered (Fig 5.6).
Placement Option 3 entails intermittent placement, leaving some gaps along the shoreline. Sometimes this
is done to concentrate the nourishment volume where it is needed most for shore protection or recreation
as in the case of Hunting Island, South Carolina, in 1991 (Kana and Mohan 1998). However, it has also been
recommended under the assumption that it is a way to maintain a benthic community in close proximity to
nourished areas from which organisms can rapidly colonize the new beach (Peterson and Bishop 2005,
Peterson et al 2006, NPS 2012b). No documented cases of intermittent nourishments are known to exist
whereby this theory can be evaluated using quantitative measurements of the benthic community
structure. If this alternative were implemented at Avon, a number of effects would have to be considered.

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First, the no-work gaps would require fill sections to be much wider along work areas to accommodate the
design volume. The total project length is relatively short at ~2.5 miles. If two 0.5-mile gaps were added to
the project, the average fill density of nourished sections would increase by ~50 percent. At initial
placement, the project sections would have to be up to 400 feet wide, tapering rapidly to no added beach
width. If gradual tapers on the order of 1,500 feet were provided, little space would be left for full sections.
This would produce a highly scalloped shoreline and lead to erosional end effects (Dean 2002). It would also
increase the vulnerability of the foredune along the unnourished segment until sand spread into the gap.
The process of sand spreading into the gaps occurred over several years after the 1991 Hunting Island
project (Kana and Mohan 1998).
Nags Head (2011) was a continuous nourishment, using offshore borrow areas along 10 miles without gaps.
Within the first three months after completion, pre- and post-project benthic monitoring documented rapid
recovery of the benthic community to comparable levels as the adjacent unnourished areas (CZR-CSE 2014).
Other projects have similarly documented rapid recovery of benthic communities within weeks to months
after large-scale continuous beach fills (Van Dolah et al 1994, USACE 2001, Jutte et al 2002).
For the reasons outlined above, Placement Option 3 is no longer considered for the proposed Avon
nourishment project.
Placement Option 4 has been used after storms in many localities because it incorporates dune nourishment
with berm nourishment. Many federal projects incorporate some form of protective dune or storm berm
above the normal dry beach level. This alternative necessarily requires placement on the face of existing
dunes leaving no undisturbed area seaward of the vegetation line as construction proceeds. The Avon
project is situated in a part of the coast subject to strong winds. As the Nags Head (2011) project
demonstrated, a significant volume of sand shifted landward by natural processes after project completion.
Post-construction measurements documented upwards of 800,000 cubic yards (~17 percent of the total
nourishment volume) shifted into the foredune and upper beach area within three years of project
completion (CSE 2014). The average post nourishment dune accretion rate at Nags Head was ~4.2 cubic
yards per foot per year for the first three years of the project (CSE 2014). Dune growth was aided by strategic
placement of sand fencing in many areas. Where existing dunes were relatively high, foredune vegetation
served as a barrier to trap wind-blown sand, mimicking the natural process of dune growth along stable
barrier beaches. The rapidity of dune growth along Nags Head provides a realistic measure of likely dune
growth rates at Avon after nourishment, given the proximity and similar exposure to winds at both sites.
The Preferred Alternative will place nearly all of the nourishment volume on the existing dry sand, wet sand,
and shallow subtidal beach. A small percentage of the fill (<10 percent) will be used to rebuild a protective
dune along sections of the Action Area that lack a foredune at the time of construction. Sand fencing will
also be incorporated into the Preferred Alternative to trap and retain nourishment sand that naturally
migrates landward upon completion of construction.

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FIGURE 5.6. Diagram showing four beach -nourishment placement options which are rejected from further analysis for the proposed
project at Avon.

[UPPER] Labeled 3 – This diagram illustrates the concept of intermittent fill whereby no-work gaps are left between nourished sections.
As discussed in the text, this placement option is not feasible for the relatively short length and high volume of nourishmen t needed
at Avon.

[SECOND] Labeled 4 – This diagram and an associated cross-section to the right show nourishment incorporating a dune and berm
with most of the material placed above the low water contour. The preferred alternative is to minimize direct sand placement on the
established dunes or back beach area s so as to avoid turtle -nesting areas of the beach.

[THIRD] Labeled 5 – This diagram and an associated cross -section to the right show nourishment placed underwater seaward of the
outer bar. In theory, such placement would eventually result in sand shifti ng landward toward the beach. However, it is difficult to
control underwater placement, and an unacceptable delay occurs before the added sand provides direct benefits in the form of a
wider beach.

[LOWER] Labeled 6 – This diagram illustrates the concept of feeder nourishment whereby all the fill is placed near the upcoast end of
the project. Over time, the material is expected to migrate downcoast, replacing lost sand. This option is rejected because t he feeder
beach would extend so far offshore that it w ould modify wave patterns and potentially cause erosion at the flanks of the feeder beach
before sand spread downcoast (Dean 2002).

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A disadvantage of Placement Option 4 is that the majority of nourishment volume is initially perched on the
existing beach above low water. This configuration is unstable and subject to large-scale erosion (profile
adjustment) until sufficient volume shifts underwater to form a stable base for the fill. Erosional
escarpments in the berm tend to persist, particularly where the berm elevation is set well above the normal
wave uprush limit. A small federal project at Hunting Island, South Carolina, designed to provide emergency
dune protection, set the berm elevation at (~)+11 feet NAVD. This was roughly 4 feet higher than the normal
dry-sand beach in the area (USACE–Charleston District, C. Mack, coastal engineer, pers. comm., December
2003) (CSE 2005b). As this highly eroding section of beach receded, escarpments 4–5 feet high persisted for
months, inhibiting turtle nesting activities, which were severely limited before nourishment due to the
highly eroded condition of the beach.
For the reasons outlined above, Placement Option 4 is rejected for the proposed Avon nourishment project.
Placement Option 5 involves nourishment along the lower foreshore well beyond the inner surf zone. Ideally,
the sediment would be deposited in water shallow enough to eventually migrate onshore and add to the
beach volume. If the material is placed too far offshore, it would likely not move into the active beach zone,
as was the case for a project off the barrier beaches flanking Mobile Bay, Alabama (Douglass 1997).
Placement control is difficult under this alternative because it is analogous to emptying a dump truck
without spreading the material evenly along the Action Area. In the case of the Mobile project, near shore
disposal was constrained by water depths needed for loaded hopper dredges. Placement was, by necessity,
in water exceeding 25 feet deep, the approximate operational depth of the loaded vessel. This placed the
material beyond the active littoral zone with little associated nourishment benefit (Douglass 1997). The
risks of such fill placement being able to meet the goals and objectives of the project are considered
unacceptably high by the Applicant.
For reasons outlined above, Placement Option 5 is rejected for the proposed Avon nourishment project.
Placement Option 6 involves nourishment along one short segment of beach at the upcoast (ie – north) end
of the project. All fill would be concentrated in that area, with the expectation of gradually feeding the
downcoast Action Area. Feeder beaches have been used adjacent to inlets and navigation projects (CERC
1984) for reasons of economy and size of dredge. Small harbor dredges working channels may only be able
to pump a distance of 2,000–4,000 feet. Therefore, the dredge spoil is placed as far away from the inlet as
practical, but not extended over long distances downcoast to other areas that may need sand. Oregon Inlet
disposal along Pea Island is an example of a feeder beach repeatedly nourished to provide sand gradually
to downcoast areas (Dolan & Lins 1986).
This concept is problematic for the Avon project for two reasons. First, the scale of the Avon nourishment
project (up to ~1.0 million cubic yards) greatly exceeds the volumes typically removed from inlet and harbor
entrances where feeder beaches have been used. An Avon feeder beach would produce a very large salient
(bulge) in the shoreline extending over 1,000 feet offshore for a limited length of beach. This would alter
wave patterns and lead to focused erosion at the ends of the feeder, with the degree of erosion related to
the scale of the feeder beach. This interruption of normal transport would increase the likelihood of a dune
breach associated with end effects of the nourishment (NRC 1995, Dean 2002). A breach of the foredune
could potentially damage NC 12 and community infrastructure.

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USACE–Wilmington District (NC) 89 Avon Village, Dare County (NC)
A variation on the feeder beach concept would stockpile a large portion of the sand somewhere along the
Action Area for later distribution by mechanical means after the turtle or bird nesting period or storm
emergencies. The primary issue with stockpiles is the lack of room along the existing dry-sand beach or
backshore area within the Action Area for a large stockpile. For example, if 50 percent, or ~500,000 cubic
yards, of the project volume were retained in a stockpile, over 300 acre-feet of storage capacity would be
required. Such a stockpile would average 20 feet high and require about 15 acres of land, which would not
be practical for the Proposed Action. Also, such a stockpile for later placement along the beach would
significantly increase the project costs (or reduce project volume) due to the need for double handling of
the nourishment sand.
For reasons outlined above, Placement Option 6 is rejected for the proposed Avon nourishment project.
5.4 Least Environmentally Damaging Practicable Alternative
In accordance with Section 404b1(CFR 40 Part 230), the US Army Corps of Engineers (USACE) must identify
the Least Environmentally Damaging Practicable Alternative (LEDPA) before it can issue a permit. The
LEDPA is the alternative that causes the least damage to the biological and physical environment and
provides protection that best preserves and enhances historical, cultural, and natural resources. The
LEDPA is identified by the Responsible Officer after weighing long-term environmental impacts against
short-term impacts when evaluating and considering what is the best protection of the resources.
The Avon project area is situated in the area of the Outer Banks known as “the Graveyard of the
Atlantic.” Since recordkeeping began in 1526, ~5,000 ships have been documented lost at sea along
the North Carolina coast (https://en.wikipedia.org/wiki/Graveyard_of_the_Atlantic). Due to its
geographical position, the ocean beach experiences more dynamic, wind and wave energy immediately
offshore and onshore, which is exacerbated by frequent storm events in the winter (November –March).
In the case of beach nourishment in a high-energy site such as Avon, the environmentally preferred
alternative may not be the most preferable alternative, because project safety during construction
must be considered above all .
While winter operation would reduce interference with nesting and migratory species, it would risk
human lives and slow the project efficiency, increasing the costs and the length of time needed to
complete it. Storms would reduce the days a dredge can be operational and would also place dredging
crews and natural resource monitors at personal risk. With summer construction, the wind would be
calmer, waves lower, and dangerous storms would be less likely to occur. Human lives would be at far
less risk, and those endangered or threatened species which may be impacted would be protected with
USFWS- and NMFS-approved mitigation procedures.
After weighing long-term environmental impacts against short -term impacts, the applicant considers
the “Preferred Alternative—Beach Nourishment With Summer Construction” the least environmentally
damaging practicable alternative for the proposed Avon beach nourishment project. Operational
productivity and human safety are the primary factors the applicant considered in recommending the
“Preferred Alternative—Beach Nourishment With Summer Construction.”

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USACE–Wilmington District (NC) 91 Avon Village, Dare County (NC)
6.0 EVALUATION FOR COMPLIANCE WITH SECTION 404(b)
As discussed in S ection 5.4, the applicant has determined that the Least Environmentally D amaging
Practicable Alternative (LEDPA) for the proposed Avon nourishment project is “Beach Nourishment with
Summer Construction.” The 2017–2018 Buxton beach nourishment project had numerous delays in the fall
and winter, and it has proved that for efficient completion and crew safety, summer construction is the
“Preferred Alternative” for the nearby proposed Avon nourishment project.
6.1 Practicable Alternative
The “No-Action Alternative” is not a practicable alternative of the three alternatives present ed for further
analysis. The beach at the Avon project area will continue to experience sand loss, and the community
would continue to experience road closures and need road repairs . The project area will continue to
experience a higher rate of erosion south of the Avon Pier, and “No-Action” would fail to address the sand
deficit along Avon beach . It is possible that emergency measures would be implemented to protect the
higher-risk properties , while the remaining beach would diminish in width . The “No-Action Alternative”
does not provide a solution to the problem of ongoing erosion , does not improve resiliency along the coast,
and does not provide enhanced or expanded habitat for threatened species that utilize the beach . No
action would cause more environmental dam age as the beach degraded, causing habitat loss while
undermining the natural beach profil e and the protective dune system. It has been determined that there
are no other practicable alternatives to the proposed nourishment in the summer months that would be
less environmentally damaging.
6.2 Candidate Disposal Site
The proposed project is a beach nourishment project, which deposits sediment from offshore borrow sites
on the beach. Disposal sites do not apply.
6.3 Potential Impacts on Physical and Chemical Characteristics of Non -Living Environment
Potential Impacts on Physical and
Chemical Characteristics N/A No Effect Negligible
Effect
Minor Effect
(Short-Term)
Minor Effect
(Long-Term)
Substrate X
Suspended Particulates/Turbidity X
Water X
Current Patterns and Water Circulation X
Normal Water Fluctuations X
Salinity Gradients X

Substrate is rated a minor effect (short -term) because the borrow-area sediments consist of sand -sized
material with minor percentages of fine -grained or coarse -grained material. Borings confirm that under -
lying sediments remainin g in the borrow areas after dredging will be similar to the dredged sediments,

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USACE–Wilmington District (NC) 92 Avon Village, Dare County (NC)
leaving a similar substrate for recolonization and use by marine organisms. Similarly, the addition of sand
to the beach will displace profiles seaward, but will lead to simila r slopes and morphology as the pre -
nourishment beach , based on the similarity of sediment grain-size distribution in the borrow areas. The
nourished beach is expected to equilibrate rapidly during fall storms following construction based on the
response t o nourishment at Nags Head (CSE 2012) and Buxton (CSE 2018).
Benthic monitoring studies in connection with a beach nourishment project at Nags Head in Dare County
(~45 miles north of Avon) demonstrated no significant difference in specie s abundance and diversity
between the borrow areas and the control areas, indicating no significant adverse impacts to the substrate
after removal of the nourishment volume (CZR–CSE 2014).
Suspended Particulates/Turbidity is rated a minor effect (short -term) because sediments in the borrow
area are relatively coarse -grained (ie – medium to coarse sand), which settle rapidly if released into the
water column. Fine -grained material (silts and clays) comprise <1 percent of the sediments in the borrow
area (see Appendix A –Geotechnical Data Analyses). This low percentage reduces the extent and duration
of turbid plumes around the dredge or at the discharge point along the beach. The borrow area is subject
to high wave energy (>15 ft waves each year), which disperses fine mate rial and results in low silt
concentrations in the upper layers. During the nearby 2017–2018 Buxton nourishment project, typical
plumes around the discharge point extended <500 ft alongshore. The plumes subsided soon after the
cessation of pumping. There is no evidence of long -term changes in turbidity along the Buxton project
area after the 201 7–2018 project. Suspended sediment characteristics along the Avon project area will
similarly fluctuate as a function of wave energy.
Water is rated no effect because borrow sediments are generally inert and do not contain foreign material
that will dissolve quickly in sea water or otherwise change water chemistry.
Current Patterns and Water Circulation are rated no effect because borrow-area excavations will be s mall
in relation to water depths offshore and, therefore, will not significantly modify wave energy over the
borrow area or along the beach. The nourished beach will maintain similar morphology and topography
as the existing beach while displacing the sho reline an average of ~60 ft seaward after equilibration of the
profile. Appendix D‒Littoral Processes contains detailed analyses and modeling of wave transformation
over the borrow areas with and without the project providing support for this effects assessment.
Normal Water Fluctuations are rated no effect because the project will not change tides or wave energy
at the shoreline. However, a wider beach will potentially reduce runup compared with highly eroded sites
in the Outer Banks where the profile is steep at the edge of the foredun e. During Hurricane Irene (2011),
runup heights along the nourished section of a construction site at Nags Head in Dare County (~45 miles
north of Avon) were measured at ~9 –9.5 ft NAVD whereas runup at Duck —where incident wave energy is
similar, but the beach is narrower —reached over 13 ft NAVD (CSE 20 12, McNinch et al 2012).
Salinity Gradients are rated no effect because the project does not involve sediments that would change
the salt content in the ocean.

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USACE–Wilmington District (NC) 93 Avon Village, Dare County (NC)
6.4 Potential Impacts on Living Communities or Human Uses
6.4.1 Potential Impacts on Biological Characteristics of Aquatic Ecosystem (Subpart D)
Potential Impacts on Biological Characteristics
Biological Characteristics N/A No
Effect
Negligible
Effect
Minor Effect
(Short-Term)
Minor Effect
(Long-Term)
Major
Effect
Threatened and endangered s pecies X
Fish, crustaceans, mollusks, and other aquatic
organisms X
Other wildlife X
6.4.1.1 Project Location, Habitats , Species
Hatteras Island is part of the string of barrier islands and spits that form the Outer Banks . It has a land
area of ~33 square miles and a population of 4,322 as of the 2010 census. Avon is one of the main tourist
centers on Hatteras Island, with a year round population of ~750 residents . Being located along the
shoreline, the Avon project area is characteris tic of the ecological habitats normally associated with
developed barrier -islands, including dunes, wet and dry beach, and ocean shore. On the sound side near
the project, maritime forests , shallow bays, temporary ponds, salt marshes , and tidal flats occu r.
Vegetation — According to NCNHP (2017), there are 11 species with some level of special status that have
been documented within a one-mile radius of the Avon proposed project area on dunes, behind the dune
line, and within marshes . Harsh conditions , such as wave and wind exposures , affect the amount of
vegetation cover on the beach and dunes. Many of the plant specie s found in these areas are well adapted
to these harsh conditions. Within the Seashore and portions of Avon on the upper beach, vegetati on cover
is a sparse (20 percent coverage) monoculture of American searocket (Cakile edentula ssp. edentula).
Vegetative cover on dune slopes ranges from sparse to dense (30 –80 percent coverage) patches of some
easily recognizable species, including sea oats (Uniola paniculata), shore little bluestem (Schizachyrium
littorale), saltmeadow cordgrass (Spartina patens), largeleaf pennywort (Hydrocotyle bonariensis) and
firewheel (Gaillardia pulchella), lanceleaf greenbrier (Smilax smallii), and prickly pear cactus (Opuntia
pusilla) [NCNHP 2017 ].
Terrestrial and Marine Wildlife — The Outer Banks, particularly the less developed sections, is a perma -
nent and temporary home to a great variety of terrestrial and aquatic life, including threatened, endan -
gered, and other protected species. These species depend on the special habitats resulting from the
transition between the northern and southern habitat zones and the dynamic nature of the barrier islands.
Special-status species are discussed in further detail as follows .
The Cape Hatteras National Seashore is designated a Globally Important Bird Area (GIBA) as a critical
natural landform along the Atlantic Flyway . The Seashore and environs serve as major resting and feeding
grounds for migratory birds throughout the year. The barrier-island ecosystem is also important to several
species of shorebirds for use as nesting grounds. Shorebirds are most abundant from late spring through

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USACE–Wilmington District (NC) 94 Avon Village, Dare County (NC)
the summer months . The Avon project area is located between two undeveloped se gments of the
Seashore , where migratory birds most often would frequent the less -developed areas offered by Hatteras
Island. The NCNHP has documented four species of birds with some level of special status within a one -
mile radius of the proposed project area (least tern, harrier, black rail, and peregrine falcon), but only the
least tern might be in the project area (NCNHP 2017).
The Outer Banks, particularly the less -developed portions, also provide s habitat for a variety of reptiles,
amphibians, mammals, and fish. Since 1996, NCNHP has documented five reptiles with spec ial status in
the project area —three species of sea turtles (loggerhead, green, and Kemp’s ridley), one coastal turtle
(diamondback terrapin), and one watersnake (Carolina watersnake). One amphibian (oak toad), one land
mammal (red wolf), one marine mammal (West Indian manatee), and two fish species (Atlantic and
shortnose sturgeon) with special status have been documented by NCNHP within one mile of the proposed
project area. The diam ondback terrapin and Carolina watersnake are both marsh dwellers and are
unlikely to occur in the proposed project area (the watersnake can also be found in freshwater habitats).
The oak toad, manatee, and red wolf are also unlikely to occur within the proposed project area. With the
exception of the sea turtles and the two sturgeon (whic h are addressed elsewhere in this document), the
other species are also unlikely to occur in the proposed project area. Many of these eleme nt occurrences
were in the back-barrier and/or terrestrial habitats , which will not be affected by the project . (NCNHP 2017)
State Natural Areas — The Turtle Pond and Cape Hatteras Lighthouse natural area is a Registered Natural
Heritage Area (RHA) under an agreement between the Natio nal Park Service and the NC Department of
Environmental Quality (NCDEQ). It is located about five miles south of the Avon project area. Within the
Turtle Pond RHA , an Interdune Pond natural community has been documented . The Buxton Woods Natural
area is located just west and southwest of the Turtle Pond RHA and a portion of the Woods is also an RHA.
The following natural communities have also been documented within the Buxton Woods Natural Area:
Interdune Marsh, Interdune Pond, Maritime Evergreen Forest (Mid-Atlantic Subtype), Maritime Shrub
Swamp (Dogwood Subtype), and Maritime Swamp Forest (Typic al Subtype). These Natural Heritage Areas
are depicted in Figure 6.1 .

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USACE–Wilmington District (NC) 95 Avon Village, Dare County (NC)
Figure 6.1. Map of Avon area and the approximate boundaries of the Hatteras Island Middle Section (the one state
Natural Heritage site located about 5 miles from the Proposed Action Area).

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USACE–Wilmington District (NC) 96 Avon Village, Dare County (NC)
6.4.1.2 Special-Status Species (Federal and State)
For federally-protected species, those listed as threatened or endangered by the USFWS or NMFS are
afforded federal protection under the ESA of 1973 (as amended) and are addressed in Section 6.4.2. Other
federal species that potentially may be affected by the propos ed project are birds and mammals. Many
bird species that may occur in the proposed project area/vicinity are federally protected under the
Migratory Bird Protection Act of 1918 (MBTA) (eg – colonial waterbirds, other shorebirds, and birds of prey ).
For M BTA-protected species, there is no provision for incidental take related to dredging or filling , or
crushing by equipment. The US Marine Mammal Protection Act of 1972 as amended (MMPA) protects all
marine mammals including cetaceans (whales, dolphins, and porpoises), pinnipeds (seals and sea lions),
sirenians (manatees and dugongs), sea otters, and polar bears within the waters of the U nited States.
For state-protected species in North Carolina, animal species designated by the NCDE Q–NCWRC and the
NCDEQ–NCNHP as threatened, endangered, or species of concern are also afforded legal protection by the
ESA (Article 25, Chapter 113, General Statutes 1987). Plant species in North Carolina —determined by the
Plant Conservation Program (NC Department of Agricultu re) and the NCNHP as threatened, endangered,
or special concern —are protected by the NC Plant Protectio n and Conservation Act of 1979.
During the preparation of Appendix E‒Biological Assessment, 26 species with special statu s were excluded
from evaluation as they were deemed not likely to occur within the proposed project area or vicinity.
Twenty-nine (29) federally or state -listed species were identified as having the potential to occur within
the proposed project area. These included 12 bird species, three fish species, two plant species, six
mammal species, and six reptile species . The 55 species considered are shown in Table 6.1. Species listed
only by the state , and not federally listed as threatened or endangered , that have the potential to occur
within the proposed project area are discussed in Section 6.4.1.7 (State-Protected Species).

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USACE–Wilmington District (NC) 97 Avon Village, Dare County (NC)
TABLE 6.1. Threatened, endangered, and candidate/proposed species with the potential to occur within the action/analysis
area as determined by state and /or federal agencies with jurisdictional authority. The species lists were obtained from
appropriate agencies (FWS, NMFS, NCNHP, and NCWRC) and reviewed; species without the potential to occur were excluded from
further review with a no -effect determination based on the rationale codes as shown below.
1 Status Codes: E/E=federally and state listed endangered; E*=state listed endangered; T/T=federally and state listed
threatened; T*=state listed threatened; SC=state listed special concern; V=state listed vulnerable; P= federally proposed for
listing; Exp=experimental population, non -essential.
2 Exclusion Rationale Codes : ODR=outside known distributional range of the species; HAB=no habitat present in analysis area; and
SEA=species not expected to occur during the season of use/impact
SPECIES COMMON AND
SCIENTIFIC NAME STATUS1 POTENTIAL
TO OCCUR RATIONALE FOR
EXCLUSION2 HABITAT DESCRIPTION AND RANGE
INVERTEBRATES1
Elkhorn coral
(Acropora palmata) T No ODR Coral reefs in southern Florida, the Bahamas, and
across the Caribbean
Staghorn coral
(Acropora cervicornis) T No ODR Back and fore reef zones in southern Florida, the
Bahamas, and across the Caribbean
BIRDS
Caspian tern
(Hydroprogne caspia) T* Yes Primarily coastal shorelines/waters but also larger
lakes and rivers of North America
Eastern black rail
(Laterallus jamaicensis
jamaicensis)
T/PT* No
Variety of heavily vegetated salt, brackish,
freshwater wetland habitats of Mexico, Central
American, Caribbean, and US east of Rockies
Piping plover
(Charadrius melodus) T/T Yes
Coastal shorelines, sandflats at the end of sand
spits and barrier islands, gently sloped foredunes,
sparsely vegetated dunes, and washovers
Red-cockaded
woodpecker
(Picoides borealis)
E (PT)/E No HAB Mature pine forests with an open understory
Roseate tern (Sterna
dougallii dougallii) E/E Yes
Nest on ends of or breaks in small barrier islands
other than NC; NEUS population may use NC
beaches as stopover during seasonal migrations
Peregrine falcon
(Falco peregrinus) E* Yes
Fall and spring migrant; uses NC beaches for
resting and as winter visitor; can be seen on
telephone poles on Pea Island/Hatteras Island. No
suitable nesting habitat in project vicinity.
Bald eagle (Haliaeetus
leucoephalus) T* Yes
Year round resident in vicinity but no nesting
habitat in project vicinity. Forages along the
seashore.
Gull-billed tern
(Gelochelidon niloctica) T* Yes
Breeding summer resident early fall migrant; rests
on sandbars and spits with other terns; feeds over
coastal grasslands, dunes, marshes
Red knot (Calidris
canuta rufa) T Yes Coastal shorelines/interitdal areas for resting and
feeding during spring and fall migration
SPECIES COMMON AND
SCIENTIFIC NAME STATUS1 POTENTIAL TO
OCCUR RATIONALE FOR
EXCLUSION2 HABITAT DESCRIPTION AND RANGE
BIRDS (concluded)
Common tern
(Sterna hirundo) E* Yes Breeds on bare sand on barrier islands and
dredge spoil islands; summer resident; more
numerous in fall migration
Least tern
(Sterna antillarum) SC Yes Open sandy beaches, sparsely vegetated areas
often on islands through the southeast US

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USACE–Wilmington District (NC) 98 Avon Village, Dare County (NC)
Black skimmer
(Rhynchops niger) SC Yes Open sandy beaches, sparsely vegetated areas
often on islands throughout southeast US,
colonial nester; mostly summer resident in NC
American oystercatcher
(Haematopus palliatus) SC Yes Coastal shoreline and estuaries, oyster beds,
mudflats, beach nester
Wilson’s plover
(Charadrius wilsonia) SC Yes Beaches, island end flats, estuarine islands
Little blue heron
(Egretta caerulea) SC No HAB Forests or thickets on maritime islands
Snowy egret (Egretta thula) SC No HAB Forests or thickets on maritime islands
Tricolored heron
(Egretta tricolor) SC No HAB Forests or thickets on maritime islands
Least bittern
(Ixobrychus exilis) SC No HAB Fresh or brackish marshes
Glossy ibis
(Plegadis falcinellus) SC No HAB Forests or thickets on maritime islands
FISHES1
Atlantic sturgeon
(Acipenser oxyrinchus) E/SC Yes Western Atlantic waters- fresh water rivers to
spawn, estuarine waters as juveniles, marine
waters as subadults and adults (10 -50m depths)
Shortnose sturgeon
(Acipenser brevirostrum ) E/E Yes Rivers and estuaries of the east coast of US
Smalltooth sawfish
(Pristis pectinata) E No ODR US DPS; shallow warm estuaries and off warm
water beaches and warm deep water reefs
Giant manta ray
(Manta birostris) T Yes
Tropical, subtropical, temperate oceans
worldwide and near productive coastlines
seasonally; estuarine waters near inlets; scattered
and fragmented populations
Oceanic whitetip shark
(Carcharhinus longimanus) T No ODR;HAB Worldwide surface waters of tropical, subtropical
offshore open ocean of >600 ft depth
FLOWERING PLANTS
Seabeach amaranth
(Amaranthus pumilus) T/T Yes Overwash flats, dunes, and accretion areas on
barrier islands of the Atlantic Ocean
Seabeach knotweed
(Polygonum glaucum) E* Yes Beach dunes and interdune swales and overwash
sands, margins of salt ponds
Georgia sunrose
(Crocanthemum georgianum) E* No HAB Maritime forests
Gulfcoast spikerush
(Eleocharis cellulosa) E* No HAB Brackish marsh

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SPECIES COMMON AND
SCIENTIFIC NAME
STATUS1 POTENTIAL TO
OCCUR
RATIONALE FOR
EXCLUSION2
HABITAT DESCRIPTION AND RANGE
FLOWERING PLANTS
Lanceleaf seedbox
(Ludwigia lanceolata) E* No HAB Brackish marsh
Florida adder’s mouth
(Malaxis spicata) SC-V No HAB Swamps, low woods, streambanks
Four angled flatsedge
(Cyperus tetragonus) SC-V No HAB Open woods, thickets, barrier islands
MAMMALS
Blue whale
(Balaenoptera
musculus)
E Yes HAB;SEA

Worldwide oceans; occasionally in coastal
waters but thought to occur generally more
offshore than other whales; poleward migration
in spring; 0 NC strandings 1997-2020; recent
documented sighting 27 mi off Cape Hatteras
Fin whale
(Balaenoptera physalus) E Yes
Deep offshore waters of all major temperate
to polar oceans; may be in NC waters during
winter migration from north to south; 3 NC
strandings 1997-2020, 1 in proposed
construction window (May)
Humpback whale
(Megaptera
novaeangliae)
E Yes
Worldwide oceans equator to subpolar; winter
migration to tropical and subtropical waters;
50 NC strandings 1997-2020, 8 from May to Oct
North Atlantic right
whale (Eubalaena
glacialis)
E Yes
Worldwide temperate to subpolar oceans;
nursery grounds in shallow coastal waters;
movements strongly tied to prey food
distribution; in lower latitudes and coastal
waters in winter, more inshore during spring
migration; 6 NC strandings 1997-2020, 2 during
proposed construction window (Aug and Sept)
Sei whale
(Balaenoptera borealis) E No HAB;SEA
Subtropical to subpolar waters on continental
edge and slope; usually observed in deeper
oceans far from coastline; move to northern
latitudes in summer; 2 NC strandings 1997-2020;
not in proposed construction window or
Dare County
Sperm whale (Physeter
macrocephalus) E Yes HAB
Worldwide oceans; uncommon in waters <300m;
9 NC strandings 1997-2020, 2 in proposed
construction window (June)
West Indian manatee
(Trichetus manatus) T/T Yes
Florida coast and Caribbean; rare visitor to
NC waters and further north; 5 NC strandings
1997-2008 all inshore, 2 in proposed
construction window (July, Aug)
Red wolf (Canis rufus) Exp/T No HAB
NC’s Albemarle peninsula, species found from
agricultural lands to pocosins in areas of low
human density, a wetland soil type, and distance
from roads.
Northern long eared bat
(Myotis septentrionalis) T/T No HAB;
NC represents southern coastal extent of range;
needs forests (live and snags) for summer roosts.
Project meets 2017 SLOPES IV.B conditions
Buxton Woods white-
footed deermouse
(Peromyscus leucopus
buxtoni)
SC No HAB Only found in maritime forest of Buxton Woods

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SPECIES COMMON AND
SCIENTIFIC NAME
STATUS1 POTENTIAL TO
OCCUR
RATIONALE FOR
EXCLUSION2
HABITAT DESCRIPTION AND RANGE
REPTILES1
Green sea turtle
(Chelonia mydas) T/T Yes
Global distribution in tropical and subtropical
waters along continents and islands; inshore and
nearshore waters of NC; nests on ocean beaches
Hawksbill sea turtle
(Eretmochelys imbricata) E Yes
Circumtropical; usually in waters <20m; rare in NC
waters but has stranded on NC beaches; nests on
ocean beaches elsewhere
Kemp’s ridley sea turtle
(Lepidochelys kempii) E/E Yes Neritic habitats including Gulf of Mexico and US
Atlantic seaboard; nests on ocean beaches
Leatherback sea turtle
(Dermochelys coriacea ) E/E Yes Pelagic species found globally, but also forages
in coastal waters; nests on ocean beaches
Loggerhead sea turtle
(Caretta caretta) T/T Yes
Circumglobal in temperate and tropical oceans;
nest on ocean beaches; critical migratory habitat
in NC offshore waters within project area
Diamondback terrapin
(Malaclemys terrapin) SC Yes Coastal salt marshes and shallow bays; nests in
sand dunes or in scrub near ocean
Carolina watersnake
(Nerodia sipedon
williamengelsi)
SC No HAB Salt or brackish marshes
Outer Banks king snake
(Lampropeltis getula
sticticeps)
SC No HAB Maritime forests, thickets, and grasslands of the
Outer Banks
Timber rattlesnake
(Crotalus horridus) SC No HAB Wetland forests in the coastal plain.
Carolina pygmy
rattlesnake
(Sistrurus miliarius)
SC No HAB Pine flatwoods, pine oak sandhills, or other
pine/oak forests
Eastern chicken turtle
(Deirochelys reticularia
reticularia syn.
Deirochelys reticularia )
SC No HAB Quiet waters, ponds, ditches, sluggsish st reams
Carolina swamp snake
(Seminatrix pygaea
paludis syn. Liodytes
pygaea paludis)
SC No HAB Lush vegetation of ponds, ditches and sluggish
streams

6.4.1.3 Migratory Bird Treaty Act (MBTA)-Protected Species
Details for each ESA -protected species are c ontained in Appendix E‒Biological Assessment. Bird species
that are federally protected under the Migratory Bird Treaty Act (MBTA) or Bald Eagle and Golden Eagle Act
are evaluated below. Other birds with federal protection include some species that are also listed by the
State of North Carolina as threatened or endangered or of special concern .

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Colonial Waterbirds, Other Shorebirds, and Birds of Prey
Caspian Tern
The largest of all the terns, the Caspian tern can be found on five
continents and is a permanent resident of but sparse breeder
on the coastal plain of North Carolina while an uncommon to
rare transient in the piedmont and mountains. The bird was
proposed for threatened state status by the NC Wildlife
Commission in 2017 but was not included in the latest State o f
North American Birds Watch List published in 2016. There is
little information on population trends, but the species appears
stable overall; however, where it is considered rare or vulnerable, it is mostly due to the scattered nature
of breeding colonie s. The 2017 survey of colonial waterbirds by the NCWRC reported a 46 percent decrease
in relative change in number of sites where the species was nesting over a 13 -year period; the number of
nests met the population goal of the North Carolina Waterbird Pr ogram only in 1993, 1995, and 1999
(Schweitzer et al 2017); the nest sites goal was met (one) in the 2020 NCWRC survey but the number of
nests goal was not (Johnson et al 2020). The 2020 NCWRC estimated number of Caspian tern nests
compared to the 14-year average declined (-16 percent) as did the number of 2020 sites compared to the
14-year mean (-100 percent) (Johnson et al 2020).
Found near large bodies of water, lakes, lagoons, beaches, and bays with a preference for quieter water, it
is seldom seen fora ging over open sea, although it may forage along the ocean beach edge. During
breeding season, it forages mostly in fresh and brackish impoundments and marshes and leaves the
saltwater habitats to other terns. It has a thick based and prominent red bill sometimes with a black tip,
a rather thick neck, and in flight, the tail has a shallow fork. A breeding adult has a black cap, frequently
raised, and the undersides of the wings are mostly white to grey with black on the outer primaries (photo
of breeding adult courtesy of Nick Rosen/Macaulay Library).
The species nests on open ground it scrapes on islands and coasts; in Dare County about 10 to 12 pairs
nest annually, but mostly in vicinity of Oregon Inlet, with fewer pair and/or less frequency near Hatter as
Inlet (LeGrand 2018 -11-09). The 13-year average of nests in North Carolina documented by the NCWRC is
18 +/- 3 at one to three sites (Schweitzer et al 2017). Each pair will typically raise only one brood per season
and a nest will contain one to three eggs. Usually a solitary bird who nest by themselves, this bird
aggressively defends the its breeding area and will chase and pursue other potentially predatory birds and
even draw blood on the head of humans who threaten too near; ironically, the entire colony will take flight
when a bald eagle appears, which then exposes the chicks to predation by gulls (Cornell University- All
About Birds 2020). The species is noteworthy for extended adolescence and prolonged care of adults for
their young for as many a s eight months. The diet of Caspian terns consists mostly of fish and it will hover
above the water, then plunge and dive below the surface to capture prey; it will also consume insects and
eggs and young of other birds. Threats to the species include pr edation and human disturbance to beach
nest areas.

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Gull-billed Tern
The gull-billed tern (Gelochelidon niloctia) is afforded federal
protection under the MBTA and is state-listed as threatened in
North Carolina (2014). It is endangered in Maryland, and is
legally protected in Virginia, Maryland, South Carolina,
Alabama, California, Louisiana, and Michigan. It is included in
the Birds of Conservation Concern (USFWS 2008) for the US
southeastern coastal plain. Without taking conservation
action, the species could become a candidate for ESA listing.
This medium-sized tern has a light gray to white body , light
gray wings tipped with black , a black bill, and black legs. Their tails are short and notched. They have a
wingspan of about 35 inches and are ~14 inches in length (https://www.audubon.org/field -guide).
Gull-billed terns are year -long residents of coastlines along North and South America and the Caribbean
Islands (http://www.allaboutbirds.org). Breeding occurs in summer along the Gulf coast from Me xico to
Florida and from Florida to New Jersey along the Atlantic coast (https://www.audubon.org/field -guide)
with most Atlantic hatching occur ring in June (USFWS 2010). The subspecies was probably extir pated in
Maryland, while population numbers have declined in Virginia, North Carolina, Florida, and possibly
Georgia (Molina and Erwin 2006). Other than Texas, where over 60 percent of the eastern subspecies
(G. niloctia arena ) was reported in 2006 , it is not considered abundant in its North American range .
In North Carolina , breeding pair numbers have declined from 1977 levels, but numbers were fairly stable
with 200–250 pairs from 2000 to 2010. State census data (2010) indicated a reduction in the number of
North Carolina colony sites and a center abundance shift from the Cape Fear River area to the northeastern
part of the state (USFWS 2010). The species tends to nest in small, scattered , and often ephemeral colonies
(Molina and Erwin 2006 ) on expose d, sparsely vegetated sandy beaches and dredge spoil sites . They feed
on mudflats, marshes, and dunes (http://www.georgiawildlife.com ).
Gull-billed terns are common in Dare County during mid -May through July where they breed, build nests,
and hatch their young. Beginning in August, the terns begin to migrate south, and by September, very few
are left. This tern leaves the North Carolina coast by November, but return s by the end of March
(http://www.ebird.org ). A 2013 NPS nesting survey conducted for it s annual Seashore colonial waterbird
study found 6 gull-billed tern nests in early June. This number is lower than previous years with 15 nests
counted in 2011 and 43 nests counted in 2012. Lower nest numbers in 2013 are likely due to habitat
changes cau sed by Hurricane Sandy (2012) and extreme winds and high tides caused by Tropical Storm
Andrea, which washed out nesting sites in early June 2013 (NPS 2013b). In 2014, only one nest was
observed resulting in no chicks ; three nests in 2015 resulting in no chicks ; and 23 nests in 2016 with a total
of 40 eggs resulting in three chicks (NPS 2014, 2015a, 2016a). The 2016 annual survey showed Ocracoke
Island remains the only nesting location for gull -billed tern in the Seashore (NPS 2016a).

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Human disturbance at nesting sites is one of the biggest threat s to gull-billed terns. Eggs and young in
nests can be crushed by vehicles, people, and pets (http://www.georgiawildlife.com ). Other losses include
elimination of natural nest sites from beach erosion, feral predation, development, perturbations to
estuarine functions, or modification of upland foraging habitats near breeding areas (Molina and Erwin
2006). Gull-billed terns are considered to be more susceptible to disturbance than other terns. Constant
disturbance of gull-billed tern nesting sites can upset important activities essential for species survival
and can even cause terns to abandon nesting sites. According to Molina and Erwin (2006), this species
often nests on man -made substrates, which suggests it could be responsive to breeding site management.
Least Tern
The least tern (Sternula antillarum) is protected under the
MBTA and is listed as special concern in North Carolina, due to
continued disturbance of nesting sites along the coast. Most
states along the Atlantic coast list the least tern as endangered,
threatened, or special concern due to loss of nesting habitat
(http://www.allaboutbirds.org ). Populations located in Cali -
fornia and the interior of US are federally listed as endangered.
It is also included in the Birds of Conservation Concern (USFWS
2008) for the US southeastern coastal plain. Without taking
conservation action, the species could become a candidate for
ESA listing.
The smallest of the American terns, least terns are ~9 inches in length with long, narrow wings reaching a
20-inch wingspan (http://www.allaboutbirds.org). Breeding plumage includes a black cap on the head,
white forehead, a short, white eyestripe , and a yellow bill with a black tip. The body shows a grayish-white
back, white underside, and short, notched tail , supported by yellow legs. During the nonbreeding season,
least terns have a black eyestripe that extends to the back of the head, a white cap, and a black bill. Males
and females look alike and immature terns appear similar to wintering adults (https://www.audubon.org/
field-guide).
Least terns build their nests on sandy or gravelly beaches or along wide, sandy river banks and lake shores .
They also may use flat gravel rooftops to nest. Guilfoyle and Fischer (2006) estimated that of the 50 percent
of all coastal pairs nesting on rooftops, 90 percent occur from Florida (both coasts) north to North Carolina.
Eastern populations occur all along the Atlantic US and Gulf Coasts and in the Caribbean during breeding
season. In Dare County, least terns begin to arrive in early April and are abundant May through August. By
the end of September, very few may remain until the beginning of October (http://www.ebird.org). By
November, all have flown south to coastal areas along Central and South America for the winter.
A traditional nesting site for the least ter n is the Cape Hatteras National Seashore. In 2013, Cape Point had
the largest colony with 329 n ests out of the 802 total observed. The 2013 total is only slightly lower than
the 832 nests observed in 2012 (NPS 2013b). Since 2007, the highest number was in 2011 with 1,063 nests,
Photo courtesy Dick Daniels, Carolina-
birds.org. Source: CZR Incorporated 2017

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much higher than the 381 nests observed in 2010 (NPS 2013b). In 2014, there were 469 nests that produced
a total of 134 chicks, which is the highest number of least tern chicks on record (NPS 201 4). The number
of nests declined in 2015 (291 nests) and 2016 (295 nests) (NPS 2015a, 2016a). For the past th ree years,
Hatteras Island had the largest number of least tern colonies. In 2018, 475 nests were identified in 14
colonies in the seashore with ~70 nests detected within the project area (NPS 2019).
The biggest threat to the least tern, and many shore birds that use sandy beaches for nesting and foraging,
is human disturbance. Recreational use, residential development, and water diversion are hazardous to
the least tern’s survival (http://www.allaboutbirds.org). As gravel rooftops are being phased out due to
storm safety concerns and energy efficiency, the loss of this alternate nesting habitat further threatens
this species. In 2010, two instances of least terns nesting on non-gravel roofs were documented in Florida,
but this is not considered a long -term alternative (Warraich et al 2012). (The two roofs had been gravel
and were previously used by nesting terns.) Despite increased development, the least tern population has
steadily increased since 1997 , with the largest colonies found at inlets (Schweitzer 2012).
Common Tern
Common terns (Sternula hirundo) are the most widespread tern species of North America. One of the most
rapidly declining beach-nesting species , the common tern was once a common nester in North Carolina .
Due to loss or disturb ance of nesting habitat, breeding popula tions have severely decreased in the last 40
years (www.ncbirds.carolinabirdclub.org ). Protected under the MBTA, the common tern is listed as a
special concern species in North Carolina and listed as threatened, en dangered, or special concern in other
states (www.ncbirds.carolinabirdclub.org ). Of medium-size ,
common terns are 12 inches long and display a 30-inch
wingspan. Males and females look similar with black caps and
wingtips, grayish -white bodies, red legs a nd bills with a black
tip, and long deeply forked tails during the breeding season
(https://www.audubon.org/field -guide). Nonbreeding and
immature terns display a partial cap, and juveniles have a
brownish head and brown stripes across their backs (http://
www.allaboutbirds.org).
Breeding areas for common terns include Canada, US states
bordering Canada, and beaches along the Atlantic coast from
Canada to North Carolina. Guilfoyle and Fischer (2006) estimated that less than 1 percent of the world
population breeds along the coast of North Carolina where they use bare sand islands, dredge islands, and
sandy beaches as nesting sites (www.ncbirds.carolinabirdclub.org ). They build nests on the ground in
shallow depressions or scrapes, sometimes with dead ve getation and shells
(http://www.allaboutbirds.org). During migrations, they may also be found around lakes and marshes.
Common tern sightings have been documented in North Carolina during the winter months, but it is
believed that these may be misidentif ications, and that common terns are absent from North Carolina

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between November and January (www.ncbirds.carolinabirdclub.org ). In 2011, the largest colonies of
common terns in the state were observed on Big Foot Island, Clark Reef, Cape Hatteras, and Cap e Lookout
National Seashore , with about one-quarter of nests built on dredged material (Schweitzer 2012). In Dare
County, common terns are mostly seen from April through October (http://www.ebird.org). They appear
in April during spring migration , some remaining to breed in the vicinity of the proposed project area while
others continue further north. Local breeders begin to leave in the fall and are joined by northern breeders
on their way south for the winter in South America.
The Cape Hatteras National Seashore is a traditional nesting site for the common tern. From 2007 to 2013,
the lowest number of nests observed was 19 (2008) and the highest number was 218 (2012), followed by a
substantial decrease to 34 nests in 2013 (NPS 2013b). The lower nest numbers are likely due to habitat
changes caused by Hurricane Sandy (2012) and extreme winds and high tides caused by Tropical Storm
Andrea that washed out nesting sites in early June 2013 (NPS 2013b). The 2018 census found 72 nests wit h
12 chicks (NPS 2019). In 2014, colonies were observed on Ocracoke Island and Green Island with a total of
38 nests that produced two chicks. The lowest number of nests occurred in 2015 , with 16 that produced
six chicks, all on Ocracoke Island (NPS 2015 a). In 2016, with colonies on Hatteras, Ocracoke, and Green
Islands, the number of nests increased to 91 , with 42 chicks (NPS 2016a). In 2014 and 2015, an increase in
laughing gulls (Leucophaeus atricilla) may have caused a lower number of common tern nests on Green
Island. Factors that threaten breeding populations along the Atlantic coast are predation, competing
gulls, pets, human disturbance, loss of nesting habitat, weather, and rising sea levels
(https://www.audubon.org/ field-guide).
Black Skimmer
Black skimmers (Rhynchops niger ) are federally protected
under the MBTA and as special concern in North Carolina
(https://www.audubon.org/field -guide). In other East coast
states, the skimmer is listed as endangered (New Jersey),
threatened (New York), or special concern (Florida ). It is
easily identified, with its striking red and black bill and short,
red legs. The black skimmer skim s the water for fish as it flies,
using its thin bill and long, lower mandible. At 18 inches long
with a 44-inch win gspan, black skimmers are medium to
large-sized waterbirds (http://www.allaboutbirds.org ). They
have long, pointed wings and a short, white tail (https://www. audubon.org/field-guide). The top of the
head, bac k, and wings are black, and the forehead and under parts are white. Skimmers have thin vertical
pupils that reduce glare from the sand and water , a trait that is highly unusual in birds. Males and females
are similar in appearance , and immature skimmers have mottled brown caps and backs
(http://www.allaboutbirds.org ). Of the three races of the black skimmer, the North American race is mainly
coastal, with the exception of some large inland lakes in Florida and California
(https://www.audubon.org/field -guide).

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During breeding season, black skimmers occupy areas ranging from Massachusetts to Texas and areas in
Central and South America. Guilfoyle and Fischer (2006) estimated that ~20 percent of the black skimmer
world-wide population breeds in the southeast US where they are found year -round. In the winter months,
skimmers are found no further north than North Carolina, and may move inland to the state’s Piedmont
region during hurricanes (https://www.audubon.org/field -guide, www.ncbirds.carolinabirdclub.org ).
Black skimmers use open sandy beaches, dredge spoil islands, sparsely vegetated shell or gravel bars, and
mats of sea wrack in salt marshes as nesting h abitats. In some instances, nests are built on rooftops
(http://www.all aboutbirds.org). They nest in groups and share nesting areas with laughing gulls and
common, least, and gull-billed tern colonies. In 2011, one-third of observed black skimmer nests built
along the North Carolina coast were on dredged material (Schweitzer 2012).
In Dare County, black skimmers can be spotted year -round, commonly April through October (breeding
season), but rarely seen December through February (http://www.ebird.org). The Seashore is a traditional
nesting site for the black skimmer with the number of nests increasing between 2007 and 2012. From 2007
to 2010, low numbers of nests were observed, ranging from 4 in 2008 to 61 in 2009; 99 and 119 nests were
observed in 20 11 and 2013, respectively. The highest number of nests was 221 in 2012 ; lower nest numbers
in 2013 were likely due to habitat changes caused by Hurricane Sandy (2012) and extreme winds and high
tides caused by Tropical Storm Andrea that wash ed out nesting sites in early June 2013 (NPS 2013b). The
number of black skimmer nests in 2014 and 2015 were below the Seashore average, with 95 nests and 85
nests, respectively, all on Ocracoke Island (NPS 2015 a, 2016a). Despite the below -average number of nests
in 2014, that year produced the highest number of chicks (54) than the previous six years. In 2016, 169 nests
with 26 chicks were observed in colonies on Cape Point and Hatteras, Ocracoke, and Green Island s (NPS
2016a). The numbers climbed significantly, reaching 368 nests with 949 eggs in 2018, of which 116 chicks
fledged (NPS 2019). Black skimmers are under the same types of threats as gulls and terns. Loss of habitat
due to human development and disturbance of nesting sites due to human recreat ional use of beaches are
major risks to their survival, along with natural predation by ghost crabs, raccoons, foxes and cyotes .
American Oystercatcher
Federally protected under the MBTA, American oystercatchers
(Haematopus palliates) are listed as endan gered, threatened,
or of special concern in almost every state along the Atlantic
Coast. I n North Carolina, they are listed as of special concern
(www.nc.audubon.org). This species is included in the Birds of
Conservation Concern for the US southeastern coastal plain
(USFWS 2008). If conservation actions are not taken, the
species could become a candi date for listing under the ESA.
American oystercatchers are unlikely to be confused with
other shorebirds , due to their bold coloring and size. They are
distinguished by long, sharp , bright red bills, stout, pale-
pinkish legs, black heads, brown backs, and white bellies. At 18 inches in length with a 32-inch wingspan,
they are one of the largest shorebird species in North America (https://www.audubon.org/field -guide). As
Photo courtesy Planetofbirds.com. Source:
CZR Incorporated 2017.

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their common name indicates, they feed almost entirely on shellfish, including oysters, limpets, clams,
mussels, crabs, starfish, sea urchins , and worms (http://www. allaboutbirds.org).
Strictly coastal birds, they use large, open , sandy areas, sand dunes, and tidal marshes as habitat. During
summer months, the American oystercatcher can be seen along the Atlantic Coast from New England to
the Gulf Coast, Mexico, and Central America, par ts of South America, and the Caribbean. About 12 percent
of the global population of American oystercatchers inhabits the United States , with one-third of that
population wintering in South Carolina. Virginia through the Carolinas has the largest concent ration of
wintering populations along the Atlantic Coast (https://www.audubon.org/field -guide).
American oystercatchers are commonly seen in Dare County throughout the year; however, numbers are
lower during winter months (http://www.ebird.org). Guilfoyle and Fischer (2006) estimated about 1,875
breeding pairs along both the Atlantic and Gulf coasts , with 1,200 pairs estimated from Florida to North
Carolina. Recent surveys from the NCWRC have shown an increase in American oystercatcher counts in
the state from a total of 701 in 2004 to 822 in 2013. Since the last survey (2010), observed pairs went from
369 to 374 in 2013 and observed singles from 25 to 74. Along the Seashore, 27 total breeding pairs were
documented in 2013 (Schweitzer and Abraham 2014). The same number of breeding pairs (27) was also
documented in 2014 , with 14 of them documented on Hatteras Island (NPS 2014). The Hatteras Island
nests (22) had seven of the nine documented fledglings for 2014.
During the 2015 breeding season, 25 pairs of American oystercatchers were documented for the C ape
Hatteras National Seashore annual natural resources report. There were 43 nests total (some pairs re -
nested) with 19 nests that hatched and produced 38 chicks (13 fledged); 2015 had the highest numb er of
nests since before 2010 (NPS 2015a). In 2016, 26 breeding pairs were observed with 41 nests (13 hatched)
that produced 24 chicks , which fledged 12 chicks (NPS 201 6a). Although nest numbers have been higher
in recent years, the fledg ling success rat e was lower than in 2010 and 2011. Breeding pairs continued to
remain stable in 2017 and 2018 (24 and 25, respectively) but only 2 chicks fledged in 2017 (out of 9 nests
hatched). There were 40 nests in 2018 hatched and 20 chicks fledged (NPS 2019).
Like many other shorebirds, loss of habitat and nesting sites, human disturbance, and predators pose the
biggest threat to the American oystercatchers ’ survival. This species is particularly sensitive to
disturbance and is more vulnerable because on average a pair may take up to four years to successfully
fledge one young (Guilfoyle and Fischer 2006). One human activity that has been beneficial is the creation
of sand islands from dredging spoils. These islands are good nesting sites because they are often high in
elevation and fairly isolated from people and predators like raccoons and skunks (http://www.allabout
birds.org).
Wilson’s Plover
Wilson’s plover (Charadrius wilsonia wilsonia ) is federally protected under the MBTA , and is listed as special
concern in North Carolina . It is state -listed as rare in Georgia, threatened in South Carolina, and
endangered in Virginia. Wilson’s Plover is listed as a Bird of Conservation Concern (USFWS 2008) and High
Concern by the US Shorebird Conservation Plan and South east Coastal Plain—Caribbean Region. The
Audubon Watch List has given it a Moderately High Priority status. After a recent reevaluation of estimated

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American shorebird populations, the Wilson’s plover was
designated as in Apparent Decline (Zdravkovic 20 13).
Three subspecies of Wilson’s plover have been identified with
only one occurring on the US Atlantic coast, C. wilsonia
wilsonia (Zdravkovic 2013). This coastal subspecies breed s
from Virginia to Florida, along the Gulf Coast from Florida to
Mexico, and in parts of the Caribbean and Central and South
America. It spend s the winter months along the Atlantic and
Gulf Coasts from Florida to Texas and south to parts of South
America. The Wilson’s plover is not considered completely
migratory because some birds stay on nesting beaches year -
long. Birds in the more northern reaches of their breeding range are known to migrate short distances
(http://www.allaboutbirds.org ).
Wilson’s plovers can be found on sparsely vegetated coastal areas, including beache s, sand bars, barrier
and dredge spoil islands, lagoons, tidal mudflats, and river mouths where fiddler crabs, their main food
source, can be found (http://www.allaboutbirds.org ). A recent study in North Carolina found 83 percent
of breeding Wilson’s plov ers on barrier island beaches (Houston and Cameron 2008). They build nests in
areas with varying vegetation ground cover from open to dense, but they prefer to build nests on sparsely
vegetated sites (Zdravkovic 2013). Wilson’s plovers nest in pairs or small groups and often return to the
same nesting site (http://www.allaboutbirds.org). In Dare County, the plover is not an abundant species,
but can be spotted from March to October. A few sightings have been documented in the first week of
November and January (http://www.ebird.org).
Guilfoyle and Fischer (2006) estimated about 1,500 breeding pairs are present on the US Southeast coastal
plain and peninsular Florida. More recent estimates put the total population of C. wilsonia wilsonia from
13,550 to 14,650 breeding adults — of those adults, about 2,000 –2,220 comprise the US Atlantic Coast
population (Zdravkovic 2013). In a comprehensive study (Houston and Cameron 2008), the coastal North
Carolina population was estimated to range from 245 to 270 bre eding pairs. A more recent North Carolina
study documented nest success rates of 46 percent for 20 nests in 2008 and 44 percent for 26 nests in 2009.
The hatched survival rates in this study were 45 percent in 2008 and 50 percent in 2009 (Zdravkovic 2013 ).
The number of nesting pairs on Hatteras Spit on Hatteras Island and Ocracoke Island have decreased, and
Oregon Inlet no longer has nesting plovers (Fussell 1994 , Zdravkovic 2013).
In 2014, three nests occurre d in the Seashore, all on islands, and no fledglings were documented (NPS
2015b). The number of nests w as the same in 2015 and 2016; all nests were located on Ocracoke Island
and no chicks fledged (NPS 2015 c, 2016a). There was no activity in the project area in 2018 (NPS 2019).
The biggest threat to the survival of Wilson’s plover is human disturbance. This includes coastal develop -
ment that alters habitat and human disturbances to nesting areas. Guilfoyle and Fischer (2006) noted that
sometimes nests and chicks have been run over by four -wheelers driven by sea turtle biologists.

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Bald Eagle
The American bald eagle (Haliaeetus leucoephalus) has been federally
protected for many years, under the MBTA and the Bald and Golden Eagle
Protection Act of 1940 (amended 1962). Because of its successful co meback
from severe population decline, the bald eagle was de -listed from federal
protection under the ESA in August 2007 . It continues to be closely monitored
so that it may be reinstated to ESA protection if needed. In North Carolina, the
bald eagle is listed as threatened and is listed in the Birds of Conservation
Concern for the US south eastern coastal plain (USFWS 2008).
The bald eagle was adopted as the national symbol of the United States of
America in 1782. This majestic bird is easily recognize d, due to its large size, its
distinctive plumage, and its sheer physical presence. Its white head and tail
feathers contrast sharply with its dark brown body and wings and bright yellow beak and taloned feet.
Juvenile bald eagles have a dark head and ta il feathers and are mottled with white on their underside
(http://www. allaboutbirds.org). Female bald eagles can weigh up to 14 pounds and have a wingspan of
about 8 ft, while male bald eagles are smaller, weighing up to 10 pounds with a wingspan of abou t 6 ft
(USFWS 2014).
Bald eagles permanent ly reside along the coast from Alaska to northern California, the Rocky Mountains,
the Great Lakes, the Mississippi River, and along the Gulf and southeast US coasts (https://www.audubon.
org/field-guide). During winter months and breeding migration, they can be seen all over the United
States. Breeding hotspots include Canada and the Great Lakes , Florida and the sou theastern US coast
(http://www.allaboutbirds.org). Bald eagles occur near water bodies—lakes, rivers, marshes, and
coastlines—where they feed on fish, their preferred food, but also birds, reptiles, crabs, and small
mammals (http://www.allabout birds.org).
In Dare County, bald eagles are common to abundant from November through April and less common May
through September (http://www.ebird.org ). Nests are usually built in tall trees in forests near large bodies
of water (http://www.allaboutbirds.org ). NCWRC bald eagle nest data show six nests in Dare County, none
of which are within the project area vicinity. These nests have not been verified by NCWRC since 2011
(David Allen, NCWRC biologist, pers comm, 18 December 2014). In the south, eagles typically breed from
late September through November and lay eggs from November through January (https://www.fws.gov
/birds/management/managed -species/bald-and-golden-eagle-information.php).
Increasingly common in North Carolina on the coast, bald eagles can be seen perching, fishing, or soaring
in coastal forest land or near maritime forests fringing marsh and creek areas. They are less likely to be
seen over the beach itself or over near shore ocean waters. Much like peregrine falcons, threats to bald
eagles include habitat destruction, poisoning, shooting, theft of eggs or young, electrocution by power
lines, and collision with moving vehicles (http://ecos.fws.gov ).
Photo courtesy NCWRC.
Source: CZR
Incorporated 2017.

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Peregrine Falcon
The peregrine falcon (Falco peregrinus anatum) has federal protection under the MBTA and is listed in the
Birds of Conservation Concern (USFWS 2008) for the southeastern coasta l plain of the US. It is also listed
as an endangered species by the State of North Carolina. After being listed as an endangered species under
the ESA for 29 years, the peregrine falcon was removed in August 1999. The post-delisting monitoring plan
has been in effect since 2003 and ended in 2015. The peregrine falcon is a crow -sized bird with a wingspan
of about 3 ft with long, pointed wings and a long tail. Adult peregrine falcons have a dark gray back and
hood that extends down their face on either side of their beak. They have a pale chest with dark horizontal
bars and spots on their abdomens and legs. Males are smaller than females, but are otherwise identic al
in appearance (USFWS 2014, http://www.all aboutbirds.org).
In North America, common ar eas with year-round falcon
residents include the western North American coast from
Alaska to Mexico, Utah, Arizona, western Colorado, around the
Great Lakes, and the northeastern portion of the US coast.
They typically breed in the summer months in Alaska and
northern Canada, the Rocky and Appalachian Mountains, and
the southern portion of South America. They build nests on
cliffs, bluffs, or tall buildings in the city. Rebounding popula-
tions are expanding their breeding and nesting areas across
North America. One of the migration routes taken by peregrine
falcons includes the Atlantic coastal areas (https://www.fws.
gov, https ://www.audubon.org/field -guide).
In Dare County, peregrine falcons are more common from Sept ember through mid-April, with the highest
numbers sighted in October. Around May, sightings decrease and are not spotted again until July. Pere-
grine falcon numbers remain low until September (http://www.ebird .org). Preferred habitats for peregrine
falcons include open areas, along lakes, river and stream banks, mudflats, coastal areas, and even in cities
where they can perch on tall structures (https://www.fws.gov). This falcon depends on shorelines,
mudflats, and areas near open water to prey on waterfowl and shorebirds. It is common in the proposed
project area during its migrations in spring (January –April) and fall (mid-September to early November),
with more abundance in October than during earlier months.
The major contributing factor to peregrine falcon decline was the pesticide DDT. Since banning the use of
DDT (31 December 1972), population recovery programs have helped establish a self -sustaining popula-
tion of peregrine falcons in the eastern US. Humans now pose the greatest threat , with habitat destruction
being the most detrimental. Poisoning, shooting, theft of eggs or young, electrocution by power lines, and
collisions with moving vehicles are also threats to this species (https://www.fws.gov ).

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6.4.1.4 Impacts on Migratory Bird Treaty Act -Protected Species by Alternatives
Additional species of birds federally protected under the Migratory Bird Protection Act (MBTA) may occur
in the project area/vicinity (eg – colonial waterbirds, other shorebirds, and birds of prey —bald eagle and
peregrine falcon). For MBTA-protected species, there is no provision for incidental take related to dredging
or filling, or crushing by equipment. “Take” under the MBTA is defined as pu rsue, hunt, shoot, wound, kill,
capture, or collect or attempt to pursue, hunt, shoot, wound, kill, capture, or collect (per 50 CFR§10.12 ).
Many of these birds also have state -level protection statu s. Below is an analysis by alternatives of the
impacts o n MBTA-Protected Species.
Impacts of “No-Action Alternative ” on Colonial Waterbirds (Caspian Tern, Gull-billed Tern, Common
Tern, Least Tern, Black Skimmer). The “No-Action Alternative” would include moderate, long-term
impacts to col onial waterbird nest ing habitat as the beach would eventually become too narrow to
support nesting. This assumes that as erosion continues, the existing foredune would leave chronic
escarpments and the dry beach would have negligible width. Existing development, which encom passes
nearly 100 percent of the proposed project oceanfront, would likely have emergency protection —such as
sand bags, installed and left in place for extended periods, further degrading habitat.
Impacts of “Preferred Alternative ‒Beach Nourishment with Summer Construction ” on Colonial
Waterbirds (Caspian Tern, Gull-billed Tern, Common Tern, Least Tern, Black Skimmer). Impacts
under “Preferred Alternative –Beach Nourishment with Summer Construction” would have direct, site -
specific, short-term, negligible to minor impacts to foraging or resting birds that may be in the area. All
four species included in the colonial waterbirds category would be present in the region, which would
increase the likelihood of disturbance by construction activities on the beach . Existing foraging and
nesting habitat would also have short -term minor impacts during sand placement. These impacts would
be staggered, however, and would progress over a 600–800-foot active impact area of the beach at any
given time as the sand is pum ped and bulldozed. Approximately 200 –300 ft of nourishment would be
completed per day, which would become immediately availab le for use by birds in the area based on their
tolerance to disturbance and proximity to human activity.
Cumulative Impacts on Co lonial Waterbirds (Caspian Tern, Gull-billed Tern, Common Tern, Least
Tern, Black Skimmer). Please refer to the Cumulative Impacts on EFH/HAPC (Sections 8 and 10) of this EA
for a description of past, present, and reasonable foreseeable future actions. Habitat loss or degradation
due to human activities associated with recreation or development elsewhere in Dare County would
continue. The “Preferred Alternative –Beach Nourishment with Summer Construction” would provide ~5
years of wider beach availab ility for bird use.
Conclusion — Colonial Waterbirds. While the level of potential impact is slightly different between the
two alternatives, each has the potential to adversely impact colonial waterbirds. W hen added to the
cumulative effects of the planned 2022 northern Outer Banks nourishment projects, north of Oregon Inlet,
periodic Oregon Inlet dredging, and continued development in Dare County —the incremental adverse impact

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on colonial waterbirds of the “No-Action Alternative” is imperceptible, and impa cts are imperceptible to
noticeable for “Preferred Alternative–Beach Nourishment with Summer Construction.”
Impacts of “No-Action Alternative ” on Wilson’s Plover. The “No-Action Alternative” would allow erosion
to continue in the proposed project area, which would have adverse, site -specific, long-term impacts to
nesting habitat for the Wilson’s plover , as the beach would eventually become too narrow to support
nesting. However, currently, this plover has not nested in the Avon project area, rarely nests along the
Seashore, and only nested on Ocracoke Island in 2014. The likelihood of isolated dune breaches and
washovers would increase under the “No-Action Alternative,” and such washovers would potentially provide
additional foraging habitat adjacent to the breach. The extent and duration of the benefit would be
temporary or short-term because it would occur around existing development , and property owners
would likely take measures to stabilize the areas around their homes.
Impacts of “Preferred Alterna tive‒Beach Nourishment with Summer Construction” on Wilson’s Plover.
This bird could be in the area from March to October, so under “Preferred Alternative‒Beach Nourishment
with Summer Construction,” not only would foraging and resting area habitats in th e proposed project area
be adversely impacted during construction (short -term), any birds in the area could also be disrupted from
feeding or resting. Beneficial, site-specific, long-term effects would include ~40‒125 additional feet of dry
beach for nesting and resting post -equilibration.
Cumulative Impacts on Wilson’s Plover. Please refer to the Cumulative Impacts on EFH/HAPC (Sections 8
and 10) of this EA for a description of past, present, and reasonable foreseeable future actions. Habitat loss
or degradation due to human activities associated with recreation or development elsewhere in Dare
County would continue. Additionally, while the proposed project area would likely revert to the pre -
project deficit condition within ~5 years under the “Preferred Alternative‒Beach Nourishment with Summer
Construction,” sand that migrates from the nourished beach downdrift within the littoral current would
feed the existing foraging and roosting habitat along the Seashore, a potential lo ng-term benefit to the
species.
Conclusion — Wilson’s Plover. Under the “No-Action Alternative,” continued erosion in the proposed
project area would cause moderate and long -term adverse impacts to nesting habitat, but if a washover
occurred, it would provide additional short -term foraging habitat. Overall, this alternative would not likely
adversely impact Wilson’s plover. Under the “Preferred Alternative‒Beach Nourishment with Summer
Construction,” impacts to nesting and foraging habitat would occur , and individual birds may be disturbed
during construction, but these are considered negligible, temporary, and short -term, and would not likely
adversely imp act Wilson’s plover. The incremental adverse impacts on Wilson’s plover of either of the two
evaluated alternatives are imperceptible when added to the cumulative adverse effects of the planned 2022
northern Outer Banks nourishment projects, periodic Oreg on Inlet dredging, and continued development in
Dare County.
Impacts of “No-Action Alternative ” on American Oystercatcher. The “No-Action Alternative” would allow
erosion to continue , which would result in less nesting habitat as the beach would continu e to steepen

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and narrow —an indirect, long-term, site-specific, adverse effect. One beneficial, indirect, site -specific
effect of this alternative would be the formation of additional foraging and resting habitat if a washover
occurred. The duration of this benefit would depend on whether the washover remained unvegetated or
stabilized with vegetation.
Impacts of “Preferred Alternative ‒Beach Nourishment with Summer Construction” on American
Oystercatcher. The “Preferred Alternative–Beach Nourishment with Summer Construction” would have
short-term, minor impacts to American oystercatcher foraging and resting habitat in the proposed project
area during sand placement. It would also have short -term, minor, local impacts to potential nesting
birds. While the nearby 2018 Buxton nourishment project was under construction in the vicinity of the
Buxton development, there were a relatively high number of nests (18) producing 34 chicks of which 20
fledged on Hatteras Island (NPS 2019). Beneficial, site -specific, long-term, moderate effects would include
~40–90 additional feet of dry beach for nesting and resting post -equilibration along Avon beach.
Cumulative Impacts on American Oystercatcher. Please refer to the Cumulative Impacts on EFH/HAPC
(Sections 8 and 10) of this EA for a description of past, present, and reasonable foreseeable future actions.
While the proposed project area would likely revert to the pre -project deficit condition within ~5 years,
sand that migrates from the nourished beach downdrift within the littoral current would feed the existing
foraging and roosting habitat along the Seashore south of the southern project terminus , a potential long-
term benefit to this species. Habitat loss or degradation due to human activities associated with recreation
or development elsewhere in Dare County would continue.
Conclusion — American Oystercatcher. With a continuing erosional beac h, the “No-Action Alternative”
has no or little benefit to the American o ystercatcher, although some habitat would be provided if a wash-
over occurred due to the narrowing beach. The “Preferred Alternative–Beach Nourishment with Summer
Construction” would have short- to long-term beneficial impacts by the addition of, or expansion of,
nesting, resting, or foraging habitat. The “Preferred Alternative” would have the short-term potential to
adversely impact nesting birds . In 2018, six nests were identified by NPS staff within the project area.
However, all but one were lost.
Long-term, the “Preferred Alternative‒Beach Nourishment with Summer Construction” may provide
beneficial impacts to nesting habitat due to a wider beach. Overall, the American oystercatcher is not
likely to be adversely impacted by either of the two evaluated alternatives. The incremental adverse
impacts on American oystercatcher of either of the two evaluated alternatives are imperceptible when added
to the cumulative effects of the planned 2022 northern Outer Banks nourishment projects, periodic Oregon
Inlet dredging, and continued deve lopment in Dare County.
Impacts of “No-Action Alternative ” on Bald Eagle. The “No-Action Alternative” would have no impact on
habitats commonl y frequented by the bald eagle.
Impacts of “Preferred Alternative ‒Beach Nourishment with Summer Construction ” on Bald Eagle.
Under the “Preferred Alternative‒Beach Nourishment with Summer Construction,” bald eagle foraging and

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resting areas would be subject to short -term and negligible impact during sand placement. Bald eagle
nest locations have not been confirmed by NCWRC since 2011 , and neither beach nourishment nor
dredging is specifically listed in the National Bald Eagle Management Guidelines (USFWS 2007 b). These
guidelines provide buffer distances for activity c ategories based on type of activity, visibility of activity
from an active eagle nest, or whether similar activity exists within one mile. Extremely loud intermittent
noises within 0.5 -mile of nests are discouraged, unless greater tolerance to the activit y is demonstrated
by eagles in the nesting area. Any impacts from noise, should they occur, would be considered site -specific
and short-term.
Cumulative Impacts on Bald Eagle. Please refer to the Cumulative Impacts on EFH/HAPC (Sections 8 and
10) of this EA for a description of past, present, and reasonable foreseeable future actions. These cumulative
effects are consider ed imperceptible to noticeable.
Conclusion — Bald Eagle. The bald eagle would experience no impact under the “No-Action Alternative”
and would not likely be adversely impacted by the “Preferred Alternative‒Beach Nourishment with Summer
Construction.” The incremental adverse impacts to the bald eagle of either of the two evaluated alternatives
are imperceptible when added to the cumulati ve adverse effects of the planned 2022 northern Outer Banks
nourishment projects north of Oregon Inlet, periodic Oregon Inlet dredging, and contin ued development in
Dare County.
Impacts of “No-Action Alternative ” on Peregrine Falcon. As there is no peregrine falcon nesting or
breeding habitat in the proposed project area or its vicinity, the “No-Action Alternative” would not affect
this falcon.
Impacts of “Preferred Alternative ‒Beach Nourishment with Summer Construction” on Peregrine
Falcon. The peregrine falcon is uncommon from May to August, becoming slightly more common in
October. Foraging habitat (near congregations of shorebirds) would have direct, site -specific, short-term,
negligible-to-minor impacts from the “Preferred Alternative‒Beach Nourishment with Summer Construc-
tion” during sand placement activities. However, as stated above, the active zone of disturbance would
range from 600 ft to 800 ft long on any given da y, and extensive foraging habitat is otherwise available.
Both these alternatives may have beneficial , long-term impacts to foraging and resting habitat of the
peregrine falcon due to the wider dry beach , which would be likely to attract shorebirds, a preferred
coastal falcon prey.
Cumulative Impacts on Peregrine Falcon. Please refer to the Cumulative Impacts on EFH/HAPC (Sections
8 and 10) of this EA for a description of past, present, and reasonable foreseeable future actions. Habitat loss
or degradation due to human activities associated with recreation or development elsewhere in Dare
County would continue. Long-term , beneficial impacts of a wider dry beach would be ~5 years for the
“Preferred Alternative–Beach Nourishment with Summer Construction.” A wider, dry beach equates to more
potential use by shorebirds, which are prey for peregrine falcon.

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Conclusion — Peregrine Falcon. The “No-Action Alternative” would have no impact and the “Preferred
Alternative‒Beach Nourishment with Summer Construction” would have direct, site-specific, short-term,
and negligible -to-minor impact. The incremental adverse impacts to peregrine falcon of either of the two
evaluated alternatives are imperceptible when added to the cumulative effects of the planned 2022
northern Outer Banks nourishment projects north of Oregon Inlet , periodic Oregon Inlet dredging, and
continued development in Dare County.
6.4.1.5 Marine Mammal Protection Act (MMPA)-Protected Species
The US Marine Mammal Protection Act (MMPA) of 1972 (amended 19 94) protects all marine mammals as
listed in Table 6.2 w ithin the waters of the United States . These include cetaceans (whales, dolphins, and
porpoises), pinnipeds (seals and sea lions), sirenians (manatees, dugongs), sea otters, and polar bears.
The MMPA was the first act the US Congress passed to specifically call for an ecosystem approach to
natural resource management and conservation. This act prohibits marine mammal take, and enacts a
moratorium on th e import, export, and sale of any marine mammal, any marine mammal part or product
within the United States. The Act defines take as the act of hunting, killing, capture, and/or harassment of
any marine mammal; or, the attempt at such. It defines harassm ent as any act of pursuit, torment , or
annoyance which has the potential to either (a) injure a marine mammal in the wild or (b) disturb a marine
mammal by causing disruption of behavioral patterns, which includes, but is not limited to, migration,
breathi ng, nursing, breeding, feeding, or sheltering.
The MMPA provides for enforcement of its prohibitions, and for the issuance of regulations to implement
its legislative goals through authority given to t he USFWS and NOAA . The USFWS was given the authority
to ensure the protection of sea otters and marine otters, walruses, polar bears, three species of manatees ,
and dugongs; NOAA was given the responsibility to conserve and manage pinnipeds, including seals, sea
lions, and cetaceans such as whales and dolphi ns.
As shown in Table 6.2 , 37 species (four earless seals, 17 oceanic dolphin s, one porpoise, three sperm
whales, five beaked whales, five rorquals, one right whale, and one manatee) have the potential to occur
in NC waters. Of these 37 species, six species have additional federal protection under the ESA and are
discussed in Appendix E‒Biological Assessment. Five of the six ESA species are under the protection of
NMFS , and one is under USFWS. The four species in Table 6.2 shown as common or abundant are described
below. Please consult Appendix E‒Biological Assessment for more details on these species.
Of the 37 marine mammals with the potential to occur in the project area, only four are considered com-
mon, uncommon/common, or common/abundant . Thirteen of the 37 are considered accidental/causal or
acciden tal/causal to rare, 11 are considered rare, and nine are considered uncommon or rare/uncommon.
Six of the 37 have federal protection under the ESA, and five of these were evaluated in Appendix E‒
Biological Assessment. The sixth species is the West Indian manatee (Trichechus manatus), which was
eliminated from analysis in the Biological Assessment due to lack of habitat in the proposed project area.

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TABLE 6.2. Marine mammals which may occur in NC waters. Only bottlenose dolphins are known to
be abundant (http://www.dpr.ncpar ks.gov/mammals/accounts.php and range limits per Webster et al. 1985).
A = abundant C = common U = uncommon R = rare X = accidental/causal
*northern limit of range **southern limit of range

PHOCIDAE (Earless seals)
Hooded seal Cystophora cristata X
Harbor seal Phoca vitulina R/U
Harp seal Pagophilus groenlandicus X/R
Gray seal Halichoerus grypus R
DELPHINIDAE (oceanic dolphins)
Killer whale Orcinus orca X/R
Rough-toothed dolphin Steno bredanensis R
Striped dolphin Stenella coeruleoalba R/U
Atlantic spotted dolphin Stenella frontalis C
Spinner dolphin Stenella longirostris X/R*
Clymene dolphin Stenella clymene R
Pantropical spotted dolphin Stenella attenuata X/R*
Short-beaked common dolphin Delphinus delphis U/C
Common bottlenose dolphin Tursiops truncatus C/A
Fraser's dolphin Lagenodelphis hosei X
Atlantic white-sided dolphin Lagenorhynchus acutus R
False killer whale Pseudorca crassidens R
Risso's dolphin Grampus griseus U
Long-finned pilot whale Globicephala melas R**
Short-finned pilot whale Globicephala macorhynchus C*
Pygmy killer whale Feresa attentuata X
Melon-headed whale Peponocephala electra X
PHOCOENIDAE (porpoises)
Harbor porpoise Phocoena phocoena U
PHYSTERIDAE (sperm whales)
Sperm whale Physeter macrocephalus U
ZIPHIIDAE (beaked whales)
Gervais; beaked whale Mesoplodon europaeus R/U
Blainville's beaked whale Mesoplodon densirostris R
True's beaked whale Mesoplodon mirus X/R
Northern bottlenose whale Hyperoodon ampullatus X/R
Cuvier's beaked whale Ziphius cavirostris U
BALAENOPTERIDAE (rorquals)
Fin whale Balaenoptera physalus R
Sei whale Balaenoptera borealis X
Common minke whale Balaenoptera acutorostrata X/R
Bryde's whale Balaenoptera edeni X
Humpback whale Megaptera novaengliae U
BALAENIDAE (bowhead and right whales)
North Atlantic right whale Eubalaena glacialis R
KOGIIDAE (small sperm whales)
Pygmy sperm whale Kogia breviceps R/U
Dwarf sperm whale Kogia simus R
TRICHECHIDAE (manatees)
West Indian manatee Trichechus manatus R

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In the following text, when the term marine mammal is used, it does not include the marine mammal species
with ESA protection addressed in Appendix E‒Biological Assessment.
Atlantic Spotted Dolphin (Stenella frontalis)
Due to uncertainties about population status and trends, the
Atlantic spotted dolphin is considered as Data Deficient by the
International Union for Conservation of Nature (IUCN). The
spotted dolphin occurs throughout the warm temperate,
subtropical, and tropical waters of the Atlantic Ocean. This
species has a widespread distribution that ranges from the US
East Coast (the Gulf of Mexico to Cape Cod, Massachusetts), the
Azores and Canary Islands, to Gabon, and Brazil .
A common-to-abundant dolphin in its range, and equally com -
mon to at times very common off the North Carolina coast, this
dolphin is found mainly in warmer waters of the Gulf Stream,
less so farther offshore. It is present in North Carolina w aters year-round , as it is not seasonally migratory.
It is often more frequently seen than the common bottlenose dolphin on boat trips, though the latter is
the most abundant cetacean in North Carolina waters.
Unlike most dolphins in North Carolina waters , this species prefers shallower inshore waters, mainly over
the continental shelf. Its status beyond the continental slope is not well -known, and perhaps the majority
of the spotted dolphins at these depths are pantropical spotted dolphin s (Stenella attenuata)
(http://www.dpr.ncparks. gov/mammals/reference.php ). A medium-build dolphin, it is quite agile and
frequently is seen leaving the water when it dives (more often than the bottlenose dol phin). They are
about 5‒7.5 ft long and weigh 220‒315 pounds. They have a robust or chunky body with a tall, falcate
dorsal fin located midway down their back. The rounded melon is separated from the moderately long
beak by a distinct crease . Their shape is often described as intermediate between a bottlenose and
pantropical spotted dolp hin [Shirihai and Jarrett (2006), referenced at the NMFS website
(http://www.nmfs.noaa.gov/pr/ species/mammals/cet aceans/spotteddolphin_atlantic.htm].
The Atlantic sp otted dolphin travels in smaller groups than other dolphins, mainly 10 –25 individuals. The
two spotted dolphin species —Pantropical and Atlantic —are easily confused , as the amount of spotting is
quite variable; some Atlantics can look spotless. Observers on Gulf Stream trips can expect to see at least
a few individuals and often a few dozen or more (http://www.dpr.ncparks.gov/mammals/reference.php ).
For management purposes, Atlantic spotted dolphins inhabiting US waters hav e been divided into two
stocks—the Northern Gulf of Mexico Stock and the Western North Atlantic Stock. The northern Gulf of
Mexico stock is estimated at 24,500 ‒38,000 animals, while the western North Atlantic stock is estimated at
36,000‒51,000 animals. Insufficient data are available on current population trends.
The mammal collections database of the Smithsonian National Museum of Natural History lists 45
stranding records for North Carolina, spread out across the year (http://collections.nmnh.si.edu/search/

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mammals/). As of 1985, 25 strandings had occurred along the North Carolina coast during most months
of the year (Webster et al 1985). One stranding was documented for Cape Hatteras National Seashore in
the 2015 marine mammal summary (NPS 2015c). No strandings for this species we re reported along the
Seashore south of the project in 2016. Atlantic spotted dolphins have been incidentally taken as bycatch
in fisheries such as gillnets and purse seines. This species has been observed interacting with various
fishing vessels, often following and feeding on discarded catch. A few animals have been har pooned for
food and bait in the Caribbean, South America, West Africa, and other of fshore islands .
Short-beaked Common Dolphin (Delphinus delphis)
Short-beaked common dolphins prefer w arm
tropical to cool temperate waters (52–88°F, 10–28°C)
that are primarily oceanic and offshore, but still
along the continental slope in waters to a depth of
650–6,500 ft (200‒2,000 m). Short-beaked common
dolphins also prefer areas where upwelling occu rs.
Although this species is found worldwide in
temperate and tropical waters, it seems to prefer the
more temperate zone in the Atlantic off the East
coast of the United States . It is seen more often from
Cape Hatteras northward than off the southern ha lf
of the North Carolina coast and is seen much less
often than common bottlenose dolphins and Atlantic spotted dolphins. The southernmost stranding
record is for Carteret County , with none at all along the southern 40 percent of the coastline. In the western
North Atlantic, they are often associated with the Gulf Stream, although in the waters off North Carolina,
it seems to favor deeper, temperate (cooler) water and is not often seen in the warm Gulf Stream waters
or close to shore.
Short-beaked common dolphins are small dolphins under 9 ft long and weigh about 440 pounds. As
adults, males are slightly larger than females. They have a rounded melon, moderately long beak, and a
sleek, but robust body with a tall, triangular, falcate dorsal fin located in the middle of the back. This
species can be identified by it s distinct bright coloration patterns. A dark gray cape extends along the back
from the beak and creates a V just below the dorsal fin on either side of the body. A yellow/tan panel
appears along the flank, between the dark cape and white ventral patch, forward of the dorsal fin. This
bold coloration forms a crisscrossing hourglass pattern. A narrow , dark stripe extends from the lower jaw
to the flipper. A complex color pattern marks the facial area and beak, which includes a dark eye patch.
This is a very active and lively species, of ten coming to boats to bow -ride. Individuals are often seen
leaping completely out of the water, so that the hourglass patt ern and amber-colored patch on its side
can be seen. Short-beaked dolphins are usually found in large social groups, averaging hundreds of
individuals, but have occasionally been seen in larger herds consisting of thousands of animals (up to at
least 10,000), known as mega -pods. These large schools are thought to consist of sub -groups of 20–30

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individuals that are possibly related or separated by age and/or sex. Groups of several dozen dolphins are
normal off North Carolina, and winter boat trips seem to offer more opportunities to see them than trips
in warmer months. At times, 100 or more can be seen on a single boat trip.
Short-beaked dolphin is common within its overall range . However, in North Carolina waters, it is fairly
common to at times common, occurring mainly north of Cape Hatteras. Forty-seven strandings for North
Carolina, all from Carteret County northward, were listed in the 2014 Smithsonian National Museum of
Natural History mammal collections (http://colle ctions.nmnh.si.edu/search/mammals/). All of these
strandings occurred between November and June with the great majority from February to April. In North
Carolina waters, the species is very rare to nearly absent in summer and most of the fall, and pres ent
mainly in the latter part of winter into early spring . One stranding was documented in 2015 and 2016 along
the C ape Hatteras National Seashore , as noted in marine mammal annual reports (NPS 2015c, 2016b).
Threats include incidental take s in a number of fisheries in the Atlantic Ocean with several types of fishing
gear, including longlines, driftnets, gillnets, and trawls. Hunting for their meat and oil also pose s a threat
in Russia and Japan and by nations bordering the Black Sea and the Mediterrane an Sea.
Common Bottlenose Dolphin (Tursiops truncatus)
Found worldwide in temperate and tropical waters
ranging from latitudes of 45°N ‒45°S, the bottlenose
dolphin is one of the most well -known species of
marine mammals in North America. It occurs in the
Atlantic all along the coastline , far offshore, and
enters estuaries and river mouths. Bottlenose
dolphin can occur year-round in North Carolina
waters and are by far the most widely distributed
cetacean from the continental shelf to the coastline.
The bottlenose dolphin has a robust body and a short,
thick beak. Their coloration ranges from light gray to
black with lighter coloration on the belly. Inshore and
offshore individuals vary in color and size. Inshore
animals are smaller and lighter in color, while offshore animals are larger, darker in coloration , and have
smaller flippers. They can sometimes be confused with the rough -toothed dolphins (Steno bredanensis),
Risso’s dolphins (Grampus griseus), and Atlantic spotted dolphins in regions of overla pping distributions.
They range in length from 6.0 ft to 12.5 ft with males slightly larger than females. Adults weigh 300 ‒1,400
pounds. This is a long-lived dolphin species with a lifespan of 40 –45 years for males and more than 50
years for females (http://www.nmfs. noaa.gov/pr/species/mammals/dolphins/bottlenose -dolphin.html).
Bottlenose dolphins are generalists and feed on a variety of prey endemic to their habitat, foraging
individually and cooperatively. Like other dolphins, bottlenose dolphins use high -frequency echolocation
to locate and capture prey. Coastal animals prey on benthic invertebrates and fish, and offshore animals

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feed on pelagic squid and fish. Bottlenose dolphins are commonly foun d in groups of 2 –15 individuals in
North Carolina waters instead of many dozens to hundreds, like those in other genera. The species is quite
active, though the ir stocky build makes them less agile than some dolphins. Typically, bottlenose dolphins
can be seen on boat trips in offshore North Carolina waters, but numbers can be matched or exceeded by
Atlantic spotted dolphins (http://www.dpr.ncparks.gov/mammals/reference.php ). This species is often
associated with pilot whales and other cetacean species.
Numerous stran ding records were reported for all 12 months , with more occurring in winter, perhaps
owing to pregnant or nursing females or young with females at that time of year. The Smithsonian
National Museum of Natural History mammal collections
(http://collections.nmnh.si.edu/search/mammals/) listed ~1,718 stranding records for North Carolina, by
far the most for any cetacean species. From July 2013 to July 2015, bottlenose dolphin populations along
the east coast from New York to Florida experienced an unusual mortality event (UME). The increase in
mortality is believed to be caused by cetacean mor billivirus. There were 1,827 documented strandings
during this two-year event, compared to an average o f 295 strandings annually prior to the UME. North
Carolina had the second -highest number of stranding s (349) behind Virginia (473). Bottlenose d olphins of
all ages were affected by the morbillivirus, and most of this species found stranded were dead
(http://www.nmfs.noaa.gov/pr/health/mmume/midatldolphins 2013.html ). Of the 57 marine mammal
strandings along the Seashore in 2015, 30 were bottlenose dolphins , of which four were found on Bodie
Island (NPS 2016c). In 2016, the total number of marine mammal strandings (37) was below the 10 -year
annual average of strandings (54). Of the 37 strandings, 28 were bottlenose dolphins (NPS 2016b).
Threats include incidental injury and mortality from fishing gear, such as gillnet, seine, trawl, and longline
commercial and recreational operations, exposure to pollutants and biotoxins, viral outbreaks, and direct
harvest in Japan and Taiwan. In 2006, the National Marine Fisheries Service implemented the Bottlenose
Dolphin Take Reduction Plan (BDTRP) to reduce the ser ious injury and mortality of Western North Atlantic
coastal bottlenose dolphins incidental to nine commercial fisheries in the United States. In addition to
multiple non-regulatory provisions for research and education, the BDTRP requires modifications of
fishing practices for small, medium, and large -mesh gillnet fisheries from New York to Florida. The BDTRP
also established seasonal closures for certain commercial fisheries in state waters. The International
Union for Conservation of Nature (IUCN) classifies bottlenose dolphin as Data Deficient.
Short-finned Pilot Whale (Globicephala macrorhynchus)
Short-finned pilot whales are found primarily in deep waters throughout tropical and subtropical areas of
the world. Four stocks are recognized in the Unit ed States: West Coast, Hawaii, Northern Gulf of Mexico,
and Western North Atlantic. They prefer warmer tropical and temperate waters and can be found at
varying distances from shore, typically in deeper waters. Their main foraging habitats are areas with a
high density of squid , but they also feed on octopus and fish, all from mo derately deep water of 1,000 ft or
more. When they are swimming and probably looking for food, pilot whales form ranks that can be more
than a half-mile long.

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Short-finned pilot whales are larger members of the dolphin group reaching average lengths of 12 ft
(females) and 18 ft (males) with a maximum male size of 24 ft. Adult weight is 2,200 to 6,600 pounds. They
have a bulbous melon head with no discernible beak.
Their dorsal fin is located far forward on the body and has
a relatively long base. Body color is black or dark brown
with a large gray saddle behind the dorsal fin. They are
polygynous (males have more than one mate) and are
often found in groups with a ratio of on e mature male to
about every eight mature females. A fairly small cetacean,
it does not emerge far out of the water like some smaller
species. It is mostly seen moving slowly, in pods of 20 or
more, at and near the water surface. The species is easily
confused with the closely related long -finned pilot whale
(Globicephala melas), which favors cooler waters.
It is common offshore throughout North Carolina waters, though mainly in warmer waters, and thus
perhaps scarce in inshore waters north of Cape Hatt eras in the colder Labrador Current. The species is
one of the more numerous cetaceans off the North Carolina coast . It is exceeded in numbers by the
common bottlenose dolphin, but is at least as numerous as the Atlantic spotted dolphin. The species is
likely resident all year in North Carolina waters , as it is not known to be strongly migratory
(http://www.dpr. ncparks.gov/mammals/reference.php).
The Smithsonian National Museum of Natur al History 2014 mammal collections lists 68 stranding records
of pilot whale for North Carolina (http://collections. nmnh.si.edu/search/mammals/). Webster et al (1995)
found a statistical difference in seasonal strandings of the species alon g the North Carolina coast with
more in the cooler months . Of the 18 stranded, all but three were between December and May. The
strandings (68) documented by the National Museum of Natural History occurred in most months of the
year, except in August and September, despite being fr equently seen offshore in warmer months. One
stranding occurred at the Cape Hatteras National Seashore in 2015.
Bycatch in fishing gear is the primary threat to pilot whales. Several types of commercial fishing gear,
including gillnets, longlines, and trawls, incidentally take short -finned pilot whales. These whales have
been documented as entangled, hooked, and captured in these various types of fishing gear. In addition,
drive fisheries that specifically target pilot whal es exist in Japan and the Lesser Antilles . The IUCN Red List
classifies the short-finned pilot whale as Lower Risk -Conservation Dependent (http://www.nmfs.
noaa.gov/pr/species/mammals/cetacEAns/pilotwhale_shortfinned.htm ).
6.4.1.6 Impacts on Marine Mammal Protection Act-Protected Species by Alternatives
As previously stated, the MMPA of 1972 (as amended) offers federal protection to marine mammals within
US waters. The MMPA prohibits marine mammal takes and enacts a moratorium on the import, export,
and sale of any marine mammal, along with any marine mammal part or product within the US. The

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following discusses the impacts on marine mammals as a whole by alt ernatives. In the text below, when
the term marine mammal is used, it does not include the marine mammal species with ESA protection
addressed in Appendix E‒Biological Assessment.
Impacts of “No-Action Alternative” on Marine Mammals. The “No-Action Alternative” would likely have
no adverse effect on marine mammals. There is a slight potential for indirect, long -term, minor, local
benefit for the West Indian manatee and common bottlenose dolphin should a breach inlet form with the
high rate of erosion expected to continue with no action. Although a very rare visitor in inland waters north
of Cape Hatteras and also seldom in the NC ocean waters north of Carte ret County, the West Indian
manatee might be found in the vicinity of the inlet or use it to go from its preferred quieter back barrier
habitats with vegetation to more saline ocean waters. The common bottlenose dolphin is the most
abundant NC visitor amo ng the 17 oceanic dolphins which may occur in NC waters and often will use inlets
and river mouths to access estuaries.
Impacts of “Preferred Alternative ‒Beach Nourishment with Summer Construction” on Marine
Mammals. Of the four species of marine mammal common or abundant in North Carolina waters, three
are found year-round (Atlantic spotted dolphin, common bottlenose dolphin, and short -finned pilot
whale) and one is found only during the winter or early spring (short -beaked common dolphin). With
the exception of the four earless seals, all of which are rare or accidental/causal but also occur in
shallower waters like the common bottlenose dolphin, most of the other marine mammals with
potential occurrence in North Carolina waters are oceanic and found fur ther offshore in deeper waters
than the Proposed Action Area. As only the common bottlenose dolphin is abundant to common and
can be found close to the beach and offshore, it is the only marine mammal likely to be impacted by
both the dredge operation and sand placement activities under either alternative; winter construction
may be more likely to affect pregnant or nursing females of this species than summer construction.
Winter construction would also be more likely to have short -term direct impacts on short-beaked
common dolphin during dredge operations compared to summer construction but this species is
usually associated with deeper waters. Noise from the dredging under either alternative would be the
source of potential adverse impact most likely to a ffect any marine mammals in the vicinity. Any of
these potential adverse impacts would be considered direct, minor, local, and short -term.
NOAA guidelines define two levels of harassment for marine mammals: Level A based on a temporary
threshold shift (1 90dB re 1 µPa for pinnipeds and 180dB re 1 µPa for cetaceans), and Level B harassment
with the potential to disturb a marine mammal in the wild by a disruption to behavioral patterns
such as migration, breeding, feeding, and sheltering (160dB re 1 µPa for imp ulse noise such as
pile driving and 120 dB re 1 µPa for continuous noise such as vessel thrusters). There is new draft
guidance on anthropogenic -sourced noise for temporary threshold shifts (TTS) and permanent
threshold shifts (PTS) based on hearing sensiti vities within certain marine mammal groups
(https://www.federalregister.gov/documents/2015/07/31/2015 -18790/draft-guidance-for-assessing-the-
effects-of-anthropogenic-sound-on-marine-mammal-hearing-acoustic). Non-impulsive sources
evaluated in the 2015 guid ance do include drilling and dB thresholds (peak and cumulative) for non -

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impulsive activities range from 174 to 230 dB depending on whether the cetacean is considered
susceptible to a low, medium, or high -frequency range. However, dredging is not one of th e activities
evaluated and the new noise thresholds do not address behavioral effects. So in the interim, as discussed
in Section 9.5 of the BA (Appendix E), noise associated with hydraulic cutterhead or hopper dredges
operating in sandy substrates are un likely to exceed either the Level A or Level B thresholds.
Cumulative Impacts on Marine Mammals. Please refer to the Cumulative Impacts on EFH/HAPC
section of this document for a description of past, present, and reasonable foreseeable future actions
(pg 174).
As the replacement of the Herbert C. Bonner Bridge by NCDOT occurred within the Seashore and not
offshore, it was not likely to adversely affect marine mammals that are found only or usually in deeper
water habitat. There are no known reports of adverse effects of construction noise associated with the
replacement bridge on the marine mammals which may use Oregon Inlet.
All of the dredging associated with Hatteras Island future projects, either in Oregon Inlet or offshore,
and sand placement during future disposal of Oregon Inlet dredged material, or beach nourishment
activities for Dare County beaches, would possibly disturb marine mammals in the vicinity of the dredge
and pumping operations (Atlantic spotted dolphin and common bottle nose dolphin primarily; other
species are most often found in deeper waters). Sand placement activities would possibly disturb
species found closer to shore in shallower water, e. g. the common bottle nose dolphin. Dredging work
associated with Oregon Inlet would also possibly disturb West Indian manatee, although it is a very rare
visitor to the ocean side of NC inlets.
Anthropogenic background sounds in the marine environment have steadily increased and are likely to
continue to increase from shipping and other uses of the ocean and inland waters. Shipping is the
dominant source of underwater noise below 300 Hz (Ross 1987, 1993 as referenced in USACE 2015). While
this level is below 1 kHz, the potential exists that this sound can mask biologically important significa nt
sounds from groups of marine mammals that produce and receive sounds in this band (eg – pinnipeds and
baleen whales such as finback and humpback). Numerous actions around fisheries activities (eg – legal
and illegal bottom -disturbing fishing gear) withi n state waters would continue and potential future actions
(offshore wind projects, offshore oil , and gas seismic testing and drilling), all have the potential to
adversely affect marine mammals .
Conclusion — Marine Mammals.
Alternative 1 –No-Action would have no adverse impact on marine mammals and may have a slight
short-term beneficial effect for two marine mammal species (West Indian manatee and common
bottlenose dolphin). Marine mammals in the offshore area during either Alternative 2 –Winter
Construction or Alternative 3 –Summer Construction dredging activities may avoid the associated noise
and turbidity which, depending on prey availability, might disrupt foraging behaviors or temporarily
mask communication. However, with the exception of the common bottlenose dolphin, most of the

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marine mammals with the potential to occur are usually associated with waters deeper than the −25
feet to −50 feet found in the vicinity of the borrow area. Common bottlenose dolphin in the shallow
waters closer to the beach during sand placement under either winter or summer construction may
also experience direct, short -term adverse impacts during pumping operations or disturbance from
other project-associated vessels, but being mobile they would be able to easily find near by suitable
habitat for foraging or other behaviors.
Overall, because both Alternative 2 –Winter Construction or Alternative 3 –Summer Construction have the
potential to temporarily affect certain behaviors of some species, both alternatives may adversely im pact
marine mammals. The incremental adverse impacts to marine mammals of any of the three evaluated
alternatives are imperceptible when added to the cumulative adverse effects of the planned 2022 northern
Outer Banks nourishment projects north of Oregon Inlet, periodic Oregon Inlet dredging, and noise from
ocean-going vessels. As of October 2020, there was a moratorium on offshore drilling in federal waters off the
coast of North Carolina, and there were no known plans for seismic surveys that may adverse ly impact marine
mammals. It is possible that there could be future initiatives to conduct offshore investigations for oil and
gas.
6.4.1.7 State-Protected Species
The two species discussed here represent the species with
the potential to occur in the proposed project area which
have only state -level protection. Within North Carolina,
endangered, threatened and special concern species have
legal protection status. Other state -protected species ,
which also have federal protection (although sometimes
with a different status), were previously discussed in the
section Federally Protected Species.
Diamondback Terrapin
The diamondback terrapin (Malaclemys terrapin) is protected by the State of North Carolina with special
concern status . Although it lacks federal protection, it does have federal status as a species of concern,
which indicates not enough is known to determine whether or not it should be considered as a candidate
for federal listing. Native to coastal states from Cape Cod (MA) to Corpus Christ i (TX), it is the only turtle
species in the temperate zone adapted to life in the salt marsh. It is found in brackish coastal waters in
habitats including coastal swamps, mangrove swamps, salt marshes, lagoons, and estuarine tidal creeks.
The females of this medium-sized hard shell turtle grow to a much larger size than males. Females reach
a maximum of 25 cm (9.8 inches), while males reach only 14 cm (5.5 inches). Coloration is highly variable,
although adult terrapin carapaces (top shells) are genera lly a shade of grey with lighter colored concentric
rings (circles inside of circles). Heads and limbs are also a shade of grey with variable spots or
blotches. Orange rings with a grey or greenish background may appear on shells, but the species can

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display a wide variety of patterns and colors, sometimes even within single populations. Feet are webbed
for strong swimming.
Cape Hatteras marks the interbreeding fulcrum between the ranges of two of the seven subspecies of this
reptile; the two subspecies compose the entire east coast population. The more northern subspecies M.
terrapin terrapin intergrades with the more southern subspecies M. terrapin centrata in the Cape Hatteras
region. Although these seven subspecies are recognized, these designations do not correspond well with
genetic data (CITES 2013). A long-lived species (~40 years), the turtle is also known for its high site fidelity ,
meaning it stays in the same area its entire life. In North Carolina, it was once so abundant, it was
considere d a nuisance.
Threats to the species include habitat degradation and loss
from urbanization since the 1700s, raccoon predation of
unprotected nests, international pet trade, sea -level rise,
beach development, incidental drowning in blue crab pots ,
and collision with vehicles particularly adult females
crossing to and from nest areas in dunes to the back barrier
sound marshes (CITES 2013).
Seabeach Knotweed
The state of North Carolina considers the seabeach knot -
weed (Polygonum glaucum ) endangered, but it is not listed for federal protection. It is found in maritime
coastal habitats from Florida to Massachusetts, which are often subject to both natural and
anthropogenic disrup tions and disturbances. An annual prostrate member of the buckwheat family,
the small narrow foliage of sea beach knotweed is bluish -green with a waxy coating (glau cous) on
sprawling fleshy stems growing from a central taproot. The leaves have inrolled margins.
On beaches, it is found seaward of dunes, above the wrack line or high s pring tide zone, and often forms
interwoven mats when growing conditions allow. It is also often found on the margins of salt ponds in
the back barrier environment and interdune swales. Flowers form from May to October and fruits from
June to September. Often subject to overwash, which may aid in seed dispersal, the seabeach knotweed
is considered a pioneer colonizer species in these dynamic conditions, although little is known about the
biology of this plant. This species was known in North Carolina from nearby Chicamacomico (~15 miles
north of Avon) prior to the initiation of dune stabilization projects in that area, but has not been seen in
recent years. This species has also been documented south of the former location of the Cape Hatteras
Lighthouse (Allison Weakley, Conservation Planner, NC Natural Heritage Program, pers comm, 8 October
2014). Known threats to the species are from vehicle traffic and dune stabilization projects.
6.4.1.8 Impacts on Species with State Protection by Action Altern ative
The diamond-back terrapin and the seabeach knotweed are the only species with state protection that
may occur in or near the project area and that may be affected by the alternatives addressed in this EA.

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These species are discussed in more detail in the previous section (Section 6.4.1.7). Potential impacts
by each alternative are discussed below.
Impacts of “No-Action Alternative” on Diamond Terrapin. The diamondback terrapin has been
documented by NPS biologists west of the Proposed Action Area o n the west side of NC 12. Therefore,
Alternative 1 –No-Action may permanently affect some existing back -barrier habitats preferred by the
diamondback terrapin, as erosion would continue under this alternative and increase the likelihood of
overwash events o r a breach in the future. While both overwash and a breach would be unpredictable
in time and duration, a breach would remove back -barrier dune and marsh areas the terrapin may
currently use for foraging, nesting, and hibernation. Overwash events would hav e the potential to bury
either active or dormant individuals or preclude the use of existing foraging or habitat. The duration of
those effects would depend on whether or not the breach closed naturally or remained open and was
temporarily bridged. Disturb ance and disruptions from erosion and overwash would continue to affect
the terrapin and its habitats. After some overwash events, some short periods of decreased traffic may
occur before NCDOT could clear NC 12, or decreased traffic may occur over longer periods if NCDOT
needs to conduct more extensive repairs to NC 12, or in the event of a breach. P ost-storm maintenance
activities conducted by NCDOT (road scraping and dune building) may have an adverse impact to a
terrapin if it attempted to cross the roa d during these activities. These impacts would be considered
short-term and minor to moderate.
Impacts of Alternative 2–Winter Construction on Diamondback Terrapin. Under Alternative 2 –Winter
Construction, the diamondback terrapin would not likely be affe cted, as no suitable habitat exists for
it within the Proposed Action Area. However, there is a chance that a project -associated support vehicle
could encounter a terrapin as it crossed NC 12, but i t would not likely be found on the ocean side of
beach dunes where much of the project activities would occur, regardless of season. In addition, the
species would be less active during the winter, which would also reduce the likelihood of an encounter
with project vehicles on NC 12 during construction.
Impacts of Alternative 3–Summer Construction on Diamondback Terrapin. While this terrapin is not
found on the ocean side of dunes in the summer, a project-associated vehicle en route from one beach
access point to another could encounter a female diamondback terrapin crossing NC 12 on her way to or
from the back barrier to a back-dune nest area. Although existing traffic is heaviest in the summer, which
raises the potential for an encounter with any vehicle, the odds are somewhat remote that it would be a
project-associated vehicle. Should an encounter occur, this type of impact would be considered short-
term and moderate. Existing habitats for this terrapin west of the dune crest to the edge of Pamlico Sound
would have no adverse impacts during summer construction and would have long-term beneficial
impacts from a wider beach in front of the dunes. There were no known incidents of interactions with the
Diamondback Terrapin during construction of the nearby 2018 Buxton nourishment project.
Cumulative Impacts on D iamondback Terrapin. Please refer to the Cumulative Impacts on EFH/HAPC
section of this document for a description of past, present, and reasonable foreseeable future actions
(pg 174). Traffic is not expected to increase as a direct result of any of the t hree alternatives; however,

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traffic on NC 12 , in general, may increase as it has historically and would likely continue with or without
the project. An increase in traffic raises the likelihood that a diamondback terrapin would be killed as
it crossed NC 1 2 between habitats. Alternative 2 –Winter Construction would provide ~3 years of storm -
surge protection to the preferred habitats of the diamondback terrapin. Alternative 3 –Summer
Construction would provide ~5 years of storm-surge protection. Habitat loss or degradation due to
human activities associated with recreation or development elsewhere in Dare County would continue.
Conclusion – Diamondback Terrapin. Any of the three alternatives would not adversely impact the
diamondback terrapin. However, Altern ative 2–Winter Construction and Alternative 3 –Summer
Construction would have the potential beneficial impact of a wider beach better protected from storm
surge and overwash. The incremental adverse impacts to diamond terrapin of any of the three evaluated
alternatives are imperceptible when added to the cumulative effects of the 2022 proposed northern Outer
Banks nourishment projects, periodic Oregon Inlet dredging, and continued development in Dare County.
Impacts of Alternative 1–No-Action on Seabeach Kno tweed. Alternative 1–No-Action would allow
erosion to continue which could increase habitat for the seabeach knotweed, as more frequent
overwash events may disperse dormant seeds into new suitable habitats formed by the overwash
deposits. The type of impact would be beneficial, indirect, site-specific, and short-term to long-term.
However, should the species colonize such a deposit, continued erosion , and other overwash events
may bury or eliminate the pioneering plants which would be a short -term, adverse, moderate impact.
Impacts of Alternative 2 and Alternative 3 on Seabeach Knotweed. Under either Alternative 2 –Winter
Construction or Alternative 3 –Summer Construction, no adverse effects are likely to occur as there is
currently no known occurrence of the seabeach knotweed, and it has not historically been found in the
Proposed Action Area. Occurrences of the seabeach knotweed has been documented south of the
former location of the Cape Hatteras Lighthouse; how ever, not within the Proposed Action Area. T he
species was last documented during monthly visits between 1989 and October 1995 at the beach south
of Cape Hatteras Lighthouse (pre-1995 location) about six miles south of the Avon project area, with no
other details as to the density of occurrence or m ore specific distances (NCNHP, Allison Weakley,
Conservation Planner, pers. comm. 10 August 2015).
Since Park Service biologists conduct surveys for this plant each year along the Seashore, they would
notify the Applicant and/or the nourishment contractor if any plants are found. Alternative 2 –Winter
Construction and Alternative 3 –Summer Construction may have beneficial effects on the seabeach
knotweed because the project is designed to widen the beach. As the nourished beach equilibrates over
time to the additional sediment in the system, Aeolian processes may also enhance the species’
preferred habitat between the wrack line and dune face. Therefore, the project under either alternative
has the potential to provide more habitats for this pioneering specie s and is not likely to threaten its
continued existence.
Cumulative Impacts on Seabeach Knotweed. Please refer to the Cumulative Impacts on EFH/HAPC
section of this document for a description of past, present, and reasonable foreseeable future actions

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(pg 174). Habitat loss or degradation due to human activities associated with recreation or development
elsewhere in Dare County would continue.
6.4.1.9 Impacts on State -Designated Natural Habitats
No state -designated natural areas or natural communities exi st within the Action Area. While the North
Carolina Natural Heritage Program (NCNHP) database shows two so -designated areas about five miles
from Avon, Turtle Pond Registered Heritage Area (RHA) and Buxton Woods, neither would experience
effects from the project activities of any of the three alternatives evaluated in this EA (see Fig 6.1).
6.4.2 Threatened and Endangered Species
Threatened and endangered species with the potential to occur in or near the project area are listed in
Table 6.1 and described in detail in Appendix E‒Biological Assessment. This section summarizes the
applicable impacts by species based on detailed review in Appendix E. Cumulative effects of the
proposed project on ESA spe cies are discussed under each species in this section a nd summarized
collectively in Chapter 8 of this EA. A determination for each ESA species is also incorporated into the
discussion in this section, then summarized in Chapter 10. The study area for the cumulative effects
analysis is the Avon project area and the region. The study area for assessment of the alternatives is the
proposed project area (offshore and beach ).
6.4.2.1 Species Considered and Evaluated
A list of all species considered as endangered, threatened, candidate, or proposed by federal a gencies was
generated. Those agencies included USFWS and NMFS. With these lists, it was determined which species
had a potential to occur within the project area under analysis (as shown in Table 6.1). Species not known
to occur or with no potential to occur in the analysis area were also documented with rationale in Table
6.1 and will not be discussed further in this document. Excluded species have been dropped from further
analysis under one or more of the following conditions:
 Does not occur and is not expected in the proposed project area during the time period activi-
ties would occur
 Occurs in habitats that are not present
 Is outside of the geograph ical or elevational range of the specie s
In addition, Table 6.1 also provided a very brief summary of the species, designated critical habitat, species
habitat requirements, and known occurrence information of species that are known or may occur in the
analysis area.
Species listed as threatened or endangered by USFWS or NMFS are afforded federal protecti on under the
ESA of 1973 as amended. The Biological Assessment (Appendix E) prepared for this project evaluated 1 9
species that had the potential to occur in the project area or vicinity and were protected under the ESA.
These 19 species included three b irds, three fish, five sea turtles, five whales, one manatee, and two plants.

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Table 6.1 indicates whether the species from the USFWS official species list and the NMFS southeast region
list (1) are known or expected to occur within the proposed project ar ea and/or within one mile, (2) have
suitable habitat present, or (3) if not, why they are excluded from further analysis. Additionally, for the
marine mammals, North Carolina stranding data collected from 1997 to 2008 were consulted to help
determine whether or not to evaluate a species in more detail (Byrd et al 2014). As indicated in Table 6.1,
of the 55 protected species listed for Dare County by the USFWS, NMFS, or NCNHP, 29 species were
determined to have the potential to occur within the project ana lysis area/vicinity (YES in the table), the
other 26 were eliminated for detailed evaluation based on habitat, seasonality, or range (NO in the table);
one of the 29 with YES was also eliminated due to habitat, seasonality, or range (sperm whale). The
evaluation included 19 species with both federal and state protection (11 birds, two fishes, one mammal,
four reptiles, and one plant), seven species with only federal protection under the ESA (one bird, one fish,
three mammals, one sea turtle, and one reptil e; one of these seven is currently proposed for listing by the
state), and two species with only state protection (one reptile and one plant). One of the 19 species was
evaluated despite the fact that habitat and season provided exclusion (blue whale). Th e blue whale was
included since it has been recently documented within 28 miles of Cape Hatte ras (Lesage et al 2017) and
two confirmed sightings were also documented off the Virginia coast in 2018 and 2019 although further
offshore than the one in North Ca rolina (Engelhaupt et al 2020). The Virginia photographs represent the
southernmost extent of sightings of the blue whale in the western Atlantic US EEZ. Only those 19 species
were addressed in this assessment (evaluated species). A No Effect determinat ion was assumed for the 26
species not evaluated in detail.
6.4.2.2 Critical Habitat Considered and Evaluated
For all federally listed species in Table 6.1, there is no critical habitat (or proposed CH) within the
immediate proposed project area . Critical habitats for piping plover and the loggerhead sea turtle are
nearby. For the piping plover, the USFWS designated critical wintering habitat at four locations on the Outer
Banks, the closest of which is Unit NC –1 Oregon Inlet. The southern boundary of Unit NC–1 is ~35 miles
north of the northernmost end of the proposed project area within the National Seashore.
For the loggerhead sea turtle, the NMFS designated the Constricted Migratory Corridor as Critical Habitat
for the northwest Atlantic Ocean logger head turtle Designated Population Segment (DPS) in July 2014.
This habitat is designated primarily because of its high use and constricted narrow width (land to west and
Gulf Stream to east). The corridor is used by juvenile and adult loggerheads migrat ing between nesting,
breeding, and foraging areas (Fig 6.2). Because of the corridor’s high use and narrow passageway, the
loggerhead sea turtle is more subject to pe rturbation.
No other critical habitat for any species is found within the proposed project area or vicinity. For a full
discussion of Critical Habitat , see Appendix E‒Biological Assessment and Appendix F‒Essential Fish Habitat
Assessment.

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6.4.3 General Methodology of Effects Determinations
The Endangered Species Act (ESA) (16 USC 1531 et. Seq.) mandates that all federal agencies consider the
potential impacts of action on federal lands on the species listed as threatened or endangered. If the
USACE determines that an action may adversely impact a federally listed species, consultation with the
USFWS is required under Section 7 of the ESA to ensure that the action would not jeopardize the continued
existence of the species, or result in the destruction or adverse modification of critical habitat.
The applicant obtained a list of rare, t hreatened, and endangered species and designated critical habitat
in close proximity to the Avon project area summarized in Appendix E‒Biological Assessment. The
evaluated alternatives could cause potential adverse impacts within the project area, includi ng possible
continued reduction of habitat due to erosion and emergency repairs, protection of existing structures
from potential direct impacts, and disruption of nesting species during construction. The principal
impacts are related to turtle nesting an d colonial waterfowl nesting.
6.4.3.1 Evaluated Species
With the exception of nesting sea turtles, surveys for other protected resources which may occur within
the 2.5-mile-long Avon beach nourishment footprint are sporadic. As the Avon project area is immediately
adjacent to undeveloped oceanfront of Cape Hatteras National Seashore, protec ted species data collected
by NPS biologists during annual surveys have been included here for context. Information from other
surveys, as available, has also been included.
Following are recent survey notes or documentation of listed species provided by biologists (drawn from
field reconnaissance) from the Cape Hatteras National Seashore and NC Wildlife Resources Commission
(NCWRC).
Piping Plover (Charadrius melodus) (T) — The species nests within the Seashore on a yearly basis,
primarily on Cape Point (~5 miles south of Avon) which has the premier habitat , and also on Bodie spit at
Oregon Inlet. No nests have ever been found within the defined project area as of 2020 according to NPS
biologists. An average of 4.2 breeding pairs were observed at Cape Point between 2015 and 2019 .
Red-cockaded Woodpecker (Picoides borealis) (E) — Habitat does not exist for this species within the
defined project area; no documentatio n of the species.
Roseate Tern (Sterna dougallii) (E) — The species may be observed along the National Seashore while
migrating along the East Coast. The majority of nesting habitat is located within the Northeast/New
England states. As of 2020, no nests of the species had been documented as occurring along the Seashore
within the past ~10 years. The bird was observed May through July 2020 at Cape Point with as many as 16
birds photographed on 15 June.

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FIGURE 6.2. [UPPER] Map of the Atlantic and Gulf Coasts of the United States s howing critical migratory
habitat for the loggerhead sea turtle. A narrow corridor (in light yellow) occurs between the North Carolina
Outer Banks and the Gulf Stream. [LOWER] Map showing critical migratory habitat designated units for the
loggerhead sea turtle off the capes of North Carolina .

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Rufa Red Knot (Calidris canutus rufa) (T) — The species is primarily observed foraging on mudflats near
points and spits. Park biologists indicate that the Avon Action Area is immediately adjacent to sections of
the National Seashore which have historically provided limited foraging area (narrow dr y beach for resting
and steep narrow slope of intertidal area for foraging) and is not preferred or rarely used by rufa red knots
in the area. Erosional processes which contribute to the lower quality of these habitats would continue
unabated. Birds in the vicinity would likely continue to prefer adjacent beaches. In 2020, only two
individual birds were observed on one survey in the Buxton Action Area, within approximately two miles
of the Avon project area.
Atlantic Sturgeon (Acipenser oxyrinchus oxyrinch us) (E) — There are n o documented instances of this
species within the project area; however , recent telemetry indicates their presence off the northern Outer
Banks predominantly in the winter. The species is typically observed within low -salinity habitat character-
istic of bays and inlets; the closest inlet (Hatteras Inlet) is located ~16 miles southwest of the proposed
project area’s southern terminus.
Shortnose Sturgeon (Acipenser brevirostrum) (E) — There are no documented instances of this species
within the proposed project area . The species is typically observed within low -salinity habitat characteris -
tic of bays and inlets; the closest in let (Hatteras Inlet) is located ~16 miles southwest of the proposed
project area’s southern terminus.
Seabeach A maranth (Amaranthus pumilus) (T) — Although habitat for this particular species is sufficient,
yearly surveys through 201 9 have yielded zero documentation of the plant within the Seashore since 2005
(USFWS 2007c). There are no historic records of this pl ant from within the proposed project area.
Red Wolf (Canis rufus) (Exp) — Habitat does not exist for this species within the defined project area; no
documentation of species.
West Indian M anatee (Trichechus manatus) (T) — Habitat does not exist for this sp ecies within the defined
project area, which is highly energetic and has little to no vegetation. Few occurrences of manatees have
been documented south of the proposed project area near inlets where manatees are likely to traverse
into brackish water to drink and to consume vegetation.
Green Sea Turtle (Chelonia mydas) (T)— This species nests on Seashore beaches on a yearly basis , but
makes up a fraction of the overall nesting turtle numbers. For the northern Outer Banks, green sea turtle
was the second most common sea turtle to nest . Over the past five years, four nests have been
documented close to the Proposed Action Area within the Cape Hattras National Seashore . Of the five
species of sea turtles that occur along the Outer Banks, green sea turtles had the highest number of
strandings from 2012 to 201 9.
Hawksbill Sea Turtle (Eretmochelys imbricata) (E) — The majority of distribution for this species is limited
to the equatorial tropics and well out of range of the proposed nourishment area. In 2015, two nests were
identified using DNA analysis of an egg from each nest on Hatteras Island near Cape Point (NPS 2015d).
This was the first occurrence of a hawksbill nest along the Seashore. No hawksbill turtles have been
sighted, but strandings have occur red prior to 2014. There have been no strandings since then .

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Kemp's Ridley Sea Turtle (Lepidochelys kempii) (E) — Primarily nesting in the Gulf of Mexico, this species
is a very rare nester at the Seashore. Only two nests have been documented over the p ast eight years on
Hatteras Island but not within the Proposed Action Area. Over the past seven years, 291 have stranded on
Hatteras Island .
Leatherback Sea Turtle (Dermochelys coriacea) — Regularly observed off the coast of the Outer Banks
during peak su mmer months, this species nests very seldom north of Cape Hatteras (majority of nesting
occurs in tropics). Only one nest, located on Ocracoke Island, has been documented within the Seashore
in the past five years , and one nest was documented in 2009 in t he northern Outer Banks.
Loggerhead Sea Turtle (Caretta caretta) (T) — The loggerhead is the most commonly observed nester on
Seashore beaches and the beaches of the northern Outer Banks. From 2010 –2020, a total of 120 nests have
been documented within t he proposed sand placement footprint . An additional 48 loggerheads have
nested within one mile north and 42 within one mile south of the Proposed Action Area .
For full species description and tables, see Appendix E‒Biological Assessment.
6.4.3.2 Effects Determination of E valuated Species
Birds — Piping Plover
Direct and Indirect Effects
The closest, documented piping plover nest was ~6.0 miles away from the project Action Area at Cape
Point (Walters et al 2020). No nests have been observed within the Action Area in the past five years. While
it is reasonable t o expect the piping plover to use the area mainly during migration, bar graphs show
observations of this bird in all months of the year , although most occu r from May to August
(http://www.ebird.org ). NPS surveys have document 126 breeding pairs at Cape Point between
1987–2019 (Table 6.3). Over the past five years, there have been an average of 4.2 breeding pairs observe d
each year. No dire ct effects to these birds are expected as a result of the offshore dredging activity, but
foraging and roosting individuals could be temporarily affected by sand placement operations.
Additionally, this species is not as likely as oth er species to occur in the area of sand placement and is very
unlikely to nest in the proposed project area. However, should the piping plover be present, direct effects
for foraging, roosting, or nesting adults would include disruptions and disturbance f rom the pipeline
application of slurry sands, movements of support vehicles, and s haping the new beach. Even so, for non -
nesting adults, the effects in a given area would be temporary as the project is predicted to cover ~800 –
1,000 ft per day within the larger context of many miles of shoreline available for foraging and roosting .
Mobile adults can easily m ove to more favorable habitat.
However, should there be any chicks in the project area, which is unlikely, direct effects would include
disturbance and interruptions in foraging activities , since the chicks are unable to fly elsewhere to forage.
Infaunal prey species in the surf zone would suffer direct effects as existing organisms would be buried in
the slurry deposit and the beach sh aping would reduce available food in the vicinity of the active impact.
Therefore, direct effects which may occur are considered short -term and temporary.

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TABLE 6.3. Number of piping plover breeding pairs by site at Cape Hatteras National Seashore (1987 –2019).
aAfter Hurricane Irene, erosion of this spit had removed all suitable breeding habitat. bTotal numbers of pairs
was 202 through 2011, but locations were not available in 1989, so percentages from the specific sites are based
on the 187 nests recorded at one of the six specific nesting areas. (Source: NPS data; Walters et al 2020)
Year Bodie
Island Spit
Cape
Point
South
Beach
Hatteras
Inlet Spita
North
Ocracoke
Spit
South
Point
Total
Pairs
1987 0 4 0 4 1 1 10
1989 ------15
1990 0 8 0 4 2 0 14
1991 0 5 0 3 5 0 13
1992 0 4 0 4 4 0 12
1993 0 5 1 3 3 0 12
1994 0 5 1 3 2 0 11
1995 0 6 1 4 2 1 14
1996 1 5 1 5 1 1 14
1997 1 4 1 3 0 2 11
1998 0 4 1 3 0 1 9
1999 0 3 1 1 0 1 6
2000 0 2 0 2 0 0 4
2001 1 1 0 1 0 0 3
2002 1 0 0 1 0 0 2
2003 0 0 0 1 0 1 2
2004 1 0 0 1 0 1 3
2005 0 0 1 1 0 1 3
2006 1 2 1 1 0 1 6
2007 1 4 0 0 0 1 6
2008 1 5 1 0 0 4 11
2009 0 5 0 0 0 4 9
2010 0 6 1 0 1 4 12
2011b 2 5 2 0 1 5 15
2012 1 8 1 0 1 4 15
2013 0 7 0 0 0 2 9
2014 0 7 0 0 1 4 12
2015 1 4 1 0 1 5 12
2016 2 6 0 0 1 2 11
2017 1 5 0 0 1 5 12
2018 0 2 0 0 0 1 3
2019 0 4 0 0 0 1 5
Total 15 126 15 45 27 53 296
Percent of
total pairsb 5.1 42.6 5.1 15.2 9.1 17.9

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Potential indirect effects could stem from the wider post -project beach. Wider beaches lead to more rapid
dune growth (Bagnold 1941) as demonstrated by the 201 7–2018 Buxton nourishment project (CSE 2020).
Along accreting beaches or where sustained nourishment is implemented, the dune field can become
stabilized to the detriment of species that prefer unvegetated washover deposits. Indirect effects are
considered insignificant with the abundance of preferred habitats , particularly Cape Point, nearby.
While burial of many benthic , surf-zone prey of the piping plover will occur during the sand pl acement, an
indirect effect on the prey population could include potential reduction on subsequent visits the following
season or year . This could affect the ability of the piping plover to refuel with enough reserves to complete
its annual life -cycle in optimum condition, or at least in the condition they might have been without the
proposed project. This effect would also be difficult to meaningfully quantify or evaluate in regard to th e
proposed project. However, as shore -protection project studies in different locations and settings have
demonstrated, compatible sediments placed on the target beach in a configuration appropriate to the
geomorphology result in a short -term impact to the infauna of the surf zone. Viable communities are
known to be present within the first year.
Studies have shown that depending on species, recolonization of beach benthos can begin as soon as 2 –6.5
months if borrow sediments are similar in grain size to the target beach as would be the case for the
proposed Avon nourishment project (USACE 2001; CZR-CSE 2013, 2014 ). The benthic organisms which
thrive in the harsh dynamics of the surf zone are well -adapted to perturbation and wide fluctuations of wave
energy, suspended sediments, transported sediments, and oth er disruptions from coastal storms which can
sometimes last over several days —conditions not dissimilar to sand placement activities of the proposed
project (Deaton et al 2010). Infauna in these disturbed environments are well -adapted by being small -
bodied and short-lived with a maximum rate of fecundity, efficient dispersal mechanisms, dense
settlement, and rapid growth rates. However, it is recognized that tube dwellers and permanent burrow
dwellers are most susceptible to these types of disturbances co mpared to more mobile organisms.
One positive direct effect for this species would include a wider beach with the potential for increased
habitat suitable for roosting and for foraging after a recovery period for the benthic organisms .
Cumulative Effects
Climate change would likely bring temperature and precipitation changes, which can significantly affect
habitats in both the short-term and the long-term, especially if the seasonality of precipitation deviates
from the norm. These types of changes are d ifficult to predict with accuracy and , therefore, it is hard to
state how such changes might affect piping plover habitat. However, most scientists think that climate
change is likely to bring more intense storms and potentially more frequent storms , but in a somewhat
unpredictable manner (www.IPCC.ch.2017).
Storms and other weather events during the piping plover breeding season (March -August) can result in
temporary displacement and disturbance to nesting birds or even wash away nests, eggs, chicks, and
breeding adults, depending on the timing and severity of the event. More powerful storms can surge and
overwash large areas of piping plover habitat even up to the toe of the foredune and beyond. Conversely,

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storms outside of breeding season may provide benefit to piping plover with new overwash areas and new
nesting and foraging habitats, but may also adversely affect existing suitable habitat by associated erosion.
Hurricanes can also affect the piping plover because of their impact on human resources, according to the
staff of the NCWRC, NCNHP, and the Seashore who monitor this species. Storm recovery that pulls staff
from resource management duties (including species monitoring or law enforcement) during piping plover
breeding season would have adve rse impacts. A hurricane after August would have no direct effect on
piping plover and for the reasons stated above could benefit or enhance habitat.
Coastal development is likely to continue throughout Dare County on both state and private lands, which
will bring added pressures of more vehicles on NC Highway 12 and more people to the Avon nourished
beach as residents or tourists. Ev en without more development, recreation on the proposed project beach
and throughout Dare County is expected to continue t o increase with a concomitant rise of tourists and
vehicles visiting the beach, especially in the summer. The summer season coincides with high produc tivity
life cycles for piping plover (mating, nesting, incubating, and fledging).
There will also like ly be increased use of the beach by surf fishers—not only in summer , but also in fall and
spring. However, such use is not likely to adversely affect piping plover prey in the surf or intertidal area.
Commercial fishing will continue in nearshore and off shore waters, which may affect the abundance of the
prey which both the fish (target and bycatch) and piping plover prefer.
The planned 2022 summer northern Outer Banks nourishment projects north of Oregon Inlet will likely
produce the same disruptions to roosting and foraging birds and habitats ; therefore, cumulative effects
to the vigor of affected migrating birds in the vicinity could be detrimental.
Interrelated and Interdependent Actions — No interrelated and interdependent actions are associated
with this project; therefore , there are no anticipated adverse effects to the piping plover from such actions.
Determination — The Proposed Action may affect and is likely to adversely affect the piping plover.
Birds — Roseate Tern
Direct and Indirect Effects
Due to rarity of appearance in the proposed project area , no direct or indirect effects to this species are
expected. Although it is a rare visitor to North Carolina, the roseate tern could be present during construc-
tion. Project‐related activity will not affect their ability to feed , because preferred locations for foraging
(shallow bays, tidal inlets and channels, sandbars) are widespread, thereby providing the rare vi sitor with
other options for foraging activities. Potential visitor(s) could attempt to rest in the project area and would
be temporarily disturbed by sand placement activities, although preferred habitat for resting (sheltered
estuaries, inshore waters, and creeks) is not found within the sand placement area. No nests have been
documented in North Carolina.

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Cumulative Effects
Please refer to the Cumulative Effects section for piping plover. The roseate tern is a rare visitor to North
Carolina and does not nest in the state, so the activities discussed above wou ld have even less likelihood to
adversely affect the roseate tern than the piping plover.
Interrelated and Interdependent Actions — No interrelated and interdependent actions are associated
with the proposed project; therefore , there are no anticipated adverse effects to the roseate tern from such
actions.
Determination — Effects to the roseate tern are considered insignificant or discountable; therefore,
the proposed project may affect, but is not likely to adversely affect , the roseate tern.
Birds — Rufa Red Knot
Direct and Indirect Effects
When compared with seven other US East Coast locations, the Outer Banks ranked last in regional impor -
tance for red knots (Dinsmore et al 1998). In addition, North Carolina observations of red kno t are
generally more numerous along the southern half of the coast and outside the proposed project area
(Carolina Bird Club 2014). No direct effects are expected to the rufa red knot species as a result of the
offshore dredging activity , but individuals could be temporarily a ffected by sand placement activities.
Because the rufa red knot forages in the surf zone and roosts on the beach, activities on the target beach
associated with sand placement, particularly from April through June, would temporarily disrupt migrat -
ing adults from foraging or roosting in the area . These disrupted activities would therefore cause expendi -
ture of energy to seek quieter loca tions and w ould temporarily reduce surf -zone prey preferred by the
species (coquina clams, mole crabs, marine w orms, and horseshoe crab eggs).
Stress and the bioenergetics impact on shorebirds from such project disturbance are very difficult to mea-
sure, although this species already suffers from asynchronies in migration timing and food supply. These
direct effects may negatively affect their ability to gain enough weight to arrive at the next stopover in an
optimal condition, which may affect their ability to successfully nest, breed, and rear young, or to
complete their migration. However, these effects are difficult t o measure, meaningfully quantify, or
evaluate.
Higher quality, more abundant roosting and foraging habitats are available north and south of the pro-
posed project area. In addition, compared to species that nest on North Carolina beaches, individual
migra ting birds do not remain very long in the vicinity and will either move to adjacent areas undist urbed
by nourishment activities or continue their migration. One beneficial, direct long-term effect for this
species would include a wider beach with the pote ntial for increased habitat suitable for roosting and for
foraging after a recovery period for the benthic organisms.
While burial of many benthic surf zone prey of the rufa red knot will occur during the sand placement, an
indirect effect on the prey po pulation could include potential reduction on subsequent visits the following

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season or year . This could affect the ability of red knot s to refuel with enough reserves to complete their
annual life-cycle in optimum condition or at least in the condition t hey might have been without the pro-
posed project. This effect would also be difficult to meaningfully quantify or evaluate in regard to th e
proposed project. However, as shore -protection project studies in different locations and settings have
demonstrated, compatible sediments placed on the target beach in a configuration appropriate to the
geomorphology result in a short -term impact to the infauna of the surf zone . Viable communities are
present within the first year; recolonization begins to occur ra pidly, depending on species.
Cumulative Effects
Please refer to the Cumulative Effects section for piping plover as the same activities have the potential to
affect resting or foraging rufa red knots that may be migrating through the project area and beyond during
the spring and early fall.
Most of the precipitous decline of the rufa red knot is tied to (1) climate change , which is likely to continue
to affect asynchrony with food supplies as the birds migrate south too soon from the Arctic , and (2) the
com mercial horseshoe crab harvest in Delaware Bay , which has severely depleted a preferred food source
during their migration. While horseshoe crab harvests have been managed since 2012 with conservation
of the rufa red knot in mind, the horseshoe crab popul ations in Delaware Bay have not yet rebounded.
Cumulative impacts from persistent stress can be inferred when a population declines. More specifically,
when combined with other stressors (such as repeated flushing while foraging or from sheltered areas
during inclement weather ), such impacts can have a cumulative negative impact on fecundity and
overwinter survival (Byrne et al 2009).
Interrelated and Interdependent Actions — No interrelated and interdependent actions are associated
with this project; therefore, there are no anticipated adverse effects to the rufa red knot from such actions.
Determination — The Proposed Action may affect and is likely to adversely affect the red knot.
Fish — Atlantic Sturgeon
Direct and Indirect Effects
Atlantic sturgeo n have been documented in the nearshore marine waters in the vicinity of the proposed
project area. T he potential exists for Atlantic sturgeon to be foraging or migrating in the waters during the
dredge and pipeline activity or during the placement of sed iments on the target beach. Their presence is
possible throughout the year, so a summer dredge window does not necessarily increase the potential for
effect. In fact, results from a recent acoustic study conducted by the Atlantic Cooperative Telemetry
Network from February 2012 to May 2014 off the coast of Cape Hatteras indicated numbers are highest in
November and March (USACE 2015). Recent data from two receivers at Oregon Inlet, over 30 miles north
of the proposed project area, show the highest number of sturgeon in the spring and fall during their
migration in and out of the inlet to the Roanoke River for spawning. It is possible that the documented
sturgeon swam close to the proposed project area on their way to the inlet as nearshore is used heavily by
sub-adults and adults during their coastal migration.

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Direct effects could include noise, turbidity, temporary interruption of access to food sources, accidental
collision with hopper dredge or support vessels, and potential loss of foraging habitat d ue to potential
changes in prey species habitat as a result of dredge activity. However, the average incidental take of
Atlantic sturgeon during all USACE -authorized dredging projects on the southeast Atlantic Coast since
1995 is 0.7 per year, and most of those incidental takes associated with dredging occur in inlets or harbors,
not offshore (David Bauman, Regional Environmental Specialist, USACE Southeast Division HQ, pers
comm, 4 September 2015). In US Gulf and Atlantic sandy borrow areas studied withi n Bureau of Ocean
Energy Management (BOEM) jurisdiction, general faunal recovery (total abundance and biomass) has been
shown to vary from 3 months to 2.5 years . H owever, the paucity of long-term studies suggest s that diver-
sity and dominants composition may take 3.5 years (Michel et al 2013).
During the 2011 Nags Head nourishment project, the lack of infilling fines in the borrow areas and accurate
placement of properly sized sediment on Nags Head beach favorably restored prey species. Within one
season, this allowed a full suite of species similar to the native beach and offshore zone to recolonize the
impact areas. By the second year, taxa richness and abundances were similar to controls (CZR –CSE 2014).
Indirect effects to the Atlantic sturgeon as a r esult of the project may include changes in the marine
nearshore bottom habitats as a result of changes in bathymetry in the offshore borrow areas used for the
project. If those changes in bathymetry occur, the suite of potential prey species might also b e altered.
However, these effects are not likely , due to construction procedures designed to minimize such changes.
Cumulative Effects
Like other species, climate change has the potential to affect the Atlantic sturgeon with changes in
temperature of th e rivers and oceans or seasonality of these changes. The variations in conditions may
affect prey species or the timing of sturgeon movements from the ocean into freshwaters. Dams in place
in spawning rivers will continue to block the migration of Atlant ic sturgeon into their native rivers. Efforts
are underway to remove some dams or improve the migration pathway by the construction of rock ramps
at some dams. These rock ramps are considered beneficial. Cumulative effects would also include
continued c ommercial fisheries that use bottom -disturbing fishing gear in particular and accidental by -
catch of all types of commercial fisheries.
Interrelated and Interdependent Actions — No interrelated and interdependent actions are associated
with this project; therefore, no adverse effects to the Atlantic sturgeon are anticipated from such actions.
Determination — Research has shown that the Atlantic sturgeon may be in the proposed project area in
higher concentrations during November and March and primarily in proximity to inlets. Although the
nearest inlet, Hatteras Inlet, is ~16 miles from the southern boundary of the proposed project, the dredge
activities may result in an incidental take , since there is much uncertainty about th e habits of this species.
Therefore, the proposed project is likely to adversely affect the Atlantic sturgeon . The USACE would
initiate formal Section 7 consultation with NMFS for the Atlantic sturgeon. The 20 20 South Atlantic
Regional Biological Opinion (SARBO) has no seasonal wi ndow restrictions for sturgeon and includes a

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Likely to A dversely Affect determination for the Atlantic Sturgeon. The pertinent 2020 SARBO PDCs will be
followed during all proposed activities to minimize potential effects .
Fish — Shortnose Sturgeon
Direct and Indirect Effects
As this species is rarely documented within the aquatic marine habitats of the proposed project area no
direct effects are expected. Shortnose sturgeon are sometimes documented in nearshore marine areas
close to inlets , but the closest inlet is ~5 miles away. There is a remote chance that a shortnose sturgeon
on its way between inlets and its estuarine and riverine habitats would be in the area and potentially
disturbed by dredging activities , but this effect is unlikely. An indirect effect would include a short -term
decline in the amount and quality of benthic foraging habitat in the borrow area , but this effect is
considered insignificant in light of the scale of the availability of similar foraging habitat nearby.
Cumulative Effects
Refer to cumulative effects for Atlantic sturgeon , which would also be considered similar for shortnose
sturgeon. However, climate change effects may affect the shortnose in different ways , since more of its life
is spent in the shallower waters of ri vers, river mouths, and estuaries. These bodies of water may respond
to changes in precipitation or temperature more quickly or with more frequent variation than the ocean
with uncertain effects to the species that use those habitats, including the shortn ose sturgeon.
Interrelated and Interdependent Actions — No interrelated and interdependent actions are associated
with this project; therefore, no adverse effects to shortnose sturgeon are anticipated from such actions.
Determination — The 2020 SARBO inc ludes a Likely to Adversely Affect determination for the shortnose
sturgeon largely due to riverine and inlet dredging activities of many USACE projects. The proposed Avon
nourishment project is not located either in proximity to a river or a nearby inlet and the species is rare in
the project area. Ther efore, the Proposed Action is not likely to adversely affect the shortnose
sturgeon.
Fish — Giant Manta Ray
Direct and Indirect Effects
First proposed for listing in 2015 by Defenders of Wildlife, NOAA Fi sheries followed with publication of their
90-day review in February of 2016; NMFS issued its Final Rule 22 January 2018 which listed the giant manta
ray as threatened throughout its range. To date, no critical habitat has been designated for the species
(NOAA 2019).
A slow moving migratory circumglobal planktivorous filter feeder, the giant manta ray is the world’s
largest ray with a wingspan up to 29 feet. Diamond shaped with wing -like pectoral fins and a wide terminal
mouth, manta rays can be one of two colors: chevron (black back white belly) or almost completely black
on both sides. Constant and distinctive patterns of belly spots can be used to identify individuals. Found
in all tropical, subtropical, and temperate oceans it can also be found seas onally near productive

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coastlines with regular upwelling where it follows zooplankton, the predominant food source. It also has
been known to frequent estuarine waters near coastal inlets; it is suspected that its depth preferences and
foraging habits are more complex than currently understood (Miller and Klimovich 2017).
Considered predominantly an oceanic species of the continental shelf or other areas where productive
upwelling occurs, it can be sometimes found in shallower waters. While documented as far north as Long
Island, they generally are not found further north than Cape Hatteras and are considered rare in the mid -
Atlantic and northeast. An Instagram video of a giant manta ray taken from the Avon Fishing Pier in July
of 2019 documented “chasin g” behavior which was speculated to be associated with courtship (NOAA
2019). Historic documentation of the giant manta ray in North Carolina include 11 individuals near Cape
Lookout one of which was a pregnant female (Coles 1916), one in the Cape Fear estuary in 1977, one in
Lockwood Folly River in 1978, one in Beaufort Inlet in 1981, and one in Bogue Sound in 1999 (Schwartz
2000). The low and widely sporadic documentation of the species in North Carolina estuaries are
considered accidental incursions of errant individuals (Medeiros et al 2015).
Never documented within the nearshore marine aquatic habitats of the Proposed Action Area or project
area and almost never documented in North Carolina north of Cape Hatteras, there is the remote
possibility that giant manta ray could be in the vicinity of the dredge operation. However, direct and
indirect effects are not likely.
Cumulative Effects
All of its habits and behaviors are not completely understood so additional threats may exist from
activities not yet described. It is likely that many of the existing threats from overutilization and bycatch,
vessel strikes, entanglement, and habitat degradation will continue despite its protected status. Its low
fecundity and apparent habitat fidelit y make it particularly vulnerable to climate change factors which
could be disruptive to past patterns of prey which are driven by variations in currents and temperatures.
Interrelated and Interdependent Actions — There are no interrelated and interdepe ndent actions
associated with this project; therefore, there are no anticipated adverse effects to giant manta ray from
such actions.
Determination — The NMFS determined a Likely to Adversely Affect while the USACE determined a Likely
to Adversely Affect f or hopper dredging and relocation trawling in the 2020 SARBO, but a Not Likely to
Adversely Affect for other activities covered by the SARBO. The 2020 SARBO covers a vast geography that
includes known congregation areas of the giant manta ray and offshore dredge locations beyond state
waters and in tropical inlets and estuaries the giant manta ray may frequent. However, the likelihood of
this species in the Proposed Action Area is very remote as it is considered generally rare north of Cape
Hatteras. A large portion of existing data are observational and incidental (usually tied to other types of
surveys), often lumped as "manta ray", aerial data may overlap which leads to potential double counts,
and rays are notoriously prone to misidentification, especi ally north of Cape Hatteras and without
photographs to corroborate (NMFS 2019 CFR 84 No. 234). Therefore, the proposed Action is not likely to
adversely affect giant manta ray .

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Flowering Plants — Seabeach Amaranth
Direct and Indirect Effects
As this species has not been documented within the proposed project area and NPS personnel perform
annual surveys in the nearest last-known location, no direct effects are expected to any existing popula-
tions of seabeach amaranth. The deteriorated condition of the beach and absence of backshore area free
of vegetation with a stable dry beach to sustain the species continues to make the project area less
suitable for the species. On some regional beaches, including Bogue Banks (NC), experience indicates
seabeach amaranth is more likely to propagate with a beach nourishment project than without a project
(CSE 2004, USACE 2006, CSE 2008). This is due to the extra width of dry beach that may be created by the
proposed beach nourishment and the additional unvegetated habitat acreage where seabeach amaranth
may propagate. Amaranth surveys were performed at Bogue Banks (NC) before and after nourishment.
Over an ~16-mile length of shoreline, the number of plants observed in August 2001 prior to nourishment
was under 35. After nourishment, seabeach amaranth increased to over 5,000 plants as mapped in August
2002, August 2003, and August 2004 (CSE 2004). Therefore, the project may increase suitable habitat,
while at the same time, earthmoving equipment associated with the project might disturb dormant seeds
and bury them or move them to a less suitable location for potential sprouting.
Cumulative Effects
Increased storm intensity or frequency could have both adverse and beneficial effects on seabeach ama -
ranth. Often colon izing species on somewhat ephemeral habitats like overwash fans, the seabeach
amaranth could benefit from increased events of this type, provided seed was available from a nearby
population or dormant seeds exposed by the erosion/deposit. Conversely, larg er, more frequent storms
could wash away or bury established populations. Coastal development and encroachment on habitat by
increased human recreational use of the dry beach will continue to have adverse effects on seabeach
amaranth.
Interrelated and Int erdependent Actions — No interrelated and interdependent actions are associated
with this project; therefore, there are no anticipated adverse effects to seabeach amaranth from such
actions.
Determination — Effects of the proposed project are considered discountable; therefore, the
Proposed Action will have no effect on seabeach amaranth.
Mammals — Whales
Direct and Indirect Effects
Five whale species as listed in Table 6.1 have the potential to occur in North Carolina waters: blue whale,
fin whale, humpbac k whale, North Atlantic right whale, and the sperm whale. A sixth species, sei whale, is
not likely to be close to the project area. The blue whale generally occurs further offshore than the other
whales, and is rarely observed close to shore. There was a recent sighting 27 miles off Cape Hatteras as
listed in Table 6.1, likely associated with the Gulf Stream. The fin whale also prefers deep offshore waters

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but may be in NC waters during winter migration. There have been three reported strandings in NC between
1997 and 2020 with one in May (proposed construction window).
The humpback whale is popular for whale watching in other states, but generally is found too far offshore
and a less frequent visitor to NC waters. There have been 50 NC strandings rep orted 1997–2020 with
strandings from May to October during the proposed construction window. Similarly, the sei whale prefers
deeper waters of the continental edge and slope , far from the coastline . Only two strandings have been
recorded in NC between 19 97 and 2020, and none in the proposed construction window.
The North Atlantic right whale is the species most likely to be observed in NC inshore waters, particularly
during the spring migration to spawning grounds off the Georgia coast. There were six st randings in NC
between 1997 –2020 with two occurring during the proposed construction window (August and September).
Noise generated as part of the dredge and pipeline operations would be one direct effect experienced
among any whale in the vicinity of the operation within range of its hearing. Short impulsive sounds and
nearby, high-frequency sounds have been documented to be disruptive to many species of marine life
including whales, other aquatic mammals, and fishes. However, aside from the occasional n ormal activity,
which may create a punctuation noise event at higher or louder frequency (such as transit maneuvers or
cavitation ), most of the noise generated during the dredge and pipeline activity would be continuous and
low range. A trailing, suction-hopper dredge operation is purported to emit sound levels at frequencies
below 500 Hz, a level generally parallel to that of a cargo ship traveling at moderate speed [Robinson et al
(2011) in CEDA Position Paper 7 November 2011 , Reine et al 2014 ].
As stated by Reine et al (2014), using the current NMFS threshold, peak source levels did not exceed
Level “A” Criterion (180dB re 1µPa rms) for injury/mortality to marine mammals during any aspect of
the dredging operations in the study. However, in this Reine et al study, noise levels exceeded 120dB
(Level B Criterion for harassment) and were measured at this level out to 1.3 miles from the source.
Some factors to consider are that smaller support vessels and the pipeline emit higher frequency noise
than the dredge itself. Also higher frequency sound attenuates faster than low frequency and pipeline
noise increases with the size of the aggregate in the pipe .
Sand size in the borrow area for the proposed project will not be large. For the dredges in the Reine e t
al (2014) study, attenuation distances for noise levels associated with eight different dredge operations
among three different dredges ranged from <0.7 mile to 1.7 miles. Section 10 of Presidential Executive
Order 13795 (America First Offshore Energy S trategy, 28 April 2017) called for a review of the 2016
technical guidance to assess the effects of anthropogenic sound on marine mammals (NOAA 2016). To
assist the Secretary of Commerce in the review, NMFS requested public comment on the 2016
memorandum for a 45-day period on 31 May 2016. As a result of this review, noise level thresholds for
marine mammals may undergo change.
While research has increased in the last decade on the biological effects of marine noise, not enough is
known to be able to confidently state a degree of injury with a particular degree of noise for a particular

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species, especially not on an individual basis. Therefore, an individual whale in close proximity to the
dredge operation could experience a temporary hearing loss if expo sed for long enough, but this is not
thought likely because the whale could move away from the noise source . The need for noise avoidance
could be considered harassment if the noise level exceeded 120 dB. Noise avoidance could affect foraging
behavior, which could lead to reduced productivity if there w ere prey in the vicinity of the noise that did
not also avoid the noise source. Noises could interfere with communication between whales in the vicinity.
An increased risk of collision with a project -associated vessel would be possible . Nourishment and renour -
ishment projects targeted for segments of the North Carolina coast that include offshore dredging may
pose potential for indirect effects.
Onboard marine mammal observers are expected to be a permit r equirement, which will greatly reduce
the potential for collision or other direct interaction with any whales in the area. In addition, if any whale
is disturbed by the noise associated with the dredge operation , it is likely to avoid the project vicinity .
Differences in Direct and Indirect Effects
As the whale most often recorded in ship strikes and collisions, the finback whale is most susceptible to
activities that result in an increase in ocean vessel traffic, addition of a new commercially targeted fishery,
or changes in methods or popularity of an existing fishery. None of these effects are expected as a result
of the proposed project.
As the whale most likely to utilize the shallower waters within the project area, especially during spring
migrati on, the North Atlantic right whale is the species with the highest likelihood of being in the
vicinity of the dredge activity. One of the rarest and most critically endangered whales, the right whale
is a some what regular fall and winter visitor to North Carolina waters and a less common visitor in the
summer when the project is proposed to occur. In the past 15 years, there has been one sighting of a
right whale during the construction window (May –October) near the proposed project area. The whale
was o bserved in July 2002, three miles north of the proposed project area and <2 miles offshore
(www.nefsc.noaa.gov/psb/surveys/ index.html ).
Cumulative Effects
In response to a rise in sea -surface temperatures from climate change, recent research has shown that
over a 27 -year period, finback whales have adapted their arrival to feeding grounds in the Gulf of St.
Lawrence by one day later each year. During the period of the stud y, researchers were surprised to find
that, despite following separate migration routes, the finback and right whales synchronized their arrival
times each year to avoid competing with each other for food (Ramp et al 2015). As whales have adapted
to many other changes in climate in the historic record, this study gives hope that these animals will
continue to adapt to the current challenges of climate change, but their response would be affe cted by the
rate of change and how adaptable their food source is to the same challe nges.
Climate change effects on t he North Atlantic right whale are tied to a tiny crustacean (Calanus finmarchi-
cus), a key food source. Without dense patches of this zoop lankton, female whales are unable to bulk up

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to prepare for calving, carry a pregnancy to term , or produce enough milk. When the concentration of
zooplankton is too low, right whales do not feed; such highly concentrated patches often occur where
currents converge or at the boundary of water of different densities. Changes of seawater temperature,
winds, and water currents can affect patch formation of zooplankton (New England Aquarium website
www.neaq.org).
Cumulative effects to the finback and North Atlantic right whales would include the continuation of current
threats , such as ensnarement in commercial fishing gear, overfishing of prey species for human or animal
food sources, and habitat degradation. In 2014, noise generated by a month-long airgun study of the
earth’s crust off North Carolina conducted by the LaMont-Doherty Earth Observatory may have been
disruptive to whales moving through the area. When added to the noise generated by proposed larger-
scale seismic testing/surveys in ocean waters fr om Delaware to Florida as part of oil/gas explora tion
activities and by pile -driving associated with the construction of offshore wind turbine clusters on the
western Atlantic continental shelf, noise may be cumulatively detrimental even if it does not ca use
measurable injury. Once constructed, offshore oil/gas platforms and wind turbines will require vessels to
supply operation and/or maintenance personnel and equipment , which will increase noise from vessel
traffic, facility operations, and will increas e the potential for ship collisions.
Interrelated and Interdependent Actions — No interrelated and interdependent actions are associated
with this project; therefore , there are no anticipated adverse effects to whales from such actions.
Determination — Effects are considered to be insignificant or discountable; therefore, the Proposed
Action may affect, but is not likely to adversely affect , any protected whale species with the potential
to occur in the project vicinity.
Mammals — West Indian Manatee
Direct and Indirect Effects
Although a very rare summer visitor in inland waters north of Cape Hatteras and also seldom in the NC
ocean waters north of Carteret County, the West Indian manatee might be found in the vicinity of, or
between, Hatteras or Oregon i nlet in the summer to access its preferred shallow vegetated back barrier
habitats away from more saline ocean waters. Noise effects on manatee may be similar to those
experienced by whales (see above text) although perhaps a manatee would not perceive th e noise from
as far away as a whale may or levels may differ slightly as the manatee is not a pinniped. In quieter
waters of canals and rivers manatees are known to avoid boats when they can escape to nearby deeper
water; boat collisions are a primary sour ce of injury and death to manatees. Along with their own
results, Gaspard et al (2015) cite other research that confirms manatees have relatively high frequency
hearing and the ability to localize sound sources from boats (fast or slow moving) as long as t he
background noise did not exceed their broad hearing range. Hopper dredge noise from propeller
cavitation, draghead vacuuming, and submerged slurry pipeline noise, was shown to interfere with
manatees' ability to detect boat noise in a river (Gerstein et al 2006) while McQueen et al (2019)
indicated a modeled masking zone distance from dredging noise of 1,680 to 13,438 feet for manatee.

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Cumulative Effects
Summer dredge work associated with Oregon Inlet could also possibly disturb West Indian manatee,
although it is a very rare visitor to the ocean side of NC inlets. Increased development of the Outer Banks
increases the likelihood of more boats in the sounds which may collide with the rare manatee summer
visitor, while an increase in temperatures of su mmer waters in North Carolina due to climate change could
attract more manatee visitors in the future and increase the opportunity for and likelihood of human
interactions. However, as winter populations may be negatively affected by the future closure of coal
plants and the warm water outfall congregations of manatees and climate change may foster more
frequent winter temperature anomalies, there may be less pressure for the males (typically) to wander
further north in the summer.
Interrelated and Interde pendent Actions — There are no interrelated and interdependent actions
associated with this project; therefore, there are no anticipated adverse effects to West Indian manatee
from such actions.
Determination — Although its appearance in North Carolina nea r Cape Hatteras is rare and there is
little to no summer preferred habitat in the project area, a summer visitor could be in vicinity of the
dredge operations; effects are considered insignificant and discountable so the Proposed Action may
affect, but is not likely to adversely affect the West Indian manatee.
Reptiles — Sea Turtles
For sea turtles occurring in the Atlantic Ocean, the applicant anticipates operating under the 2020 SARBO
(NMFS 2020) and associated incidental take allocation for the potential risk of a lethal take of green,
loggerhead, hawksbill, and/or Kemp’s ridley sea turtles d uring dredge operations for the proposed project.
[The 1997 SARBO (NMFS 1997) indicates that while leatherback sea turtles may be in the area of hopper
dredge operations in inlets or along the coast, the species is not likely to be adversely affected by those
operations.] Consultation for in-water impacts to these marine species will occur between the lead federal
agency (USACE) and NMFS upon publication of the permi t application and supporting documents. The
applicant acknowledges the need for compliance with all current recommendations and conditions of the
2020 SARBO, as well as future revisions to the SARBO should they occur during the timeframe of the
proposed project.
Direct and Indirect Effects
Non-breeding sea turtles of all five species with potential to be affected can be found in the nearshore
waters in the proposed project area during much of the year and may be disturbed by increased turbidity
or disrupted while swimming during dredging activities (NPS 2013c). During sand placement activities,
the primary direct effects on sea turtles that may nest on the beach include disturbance during nesting
and the potential for escarpments and compaction of beach sand. Large escarpments can impede access
to nesting areas, increase the number of false crawls, or cause a turtle to lay eggs in a location subject to
overwash (Byrd 2004). Sand compaction can affect digging behavior and result in false crawls, c an affect

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incubation temperature , which in turn affects sex ratios, and can affect gas exchange parameters within
incubating nests (Mrosovsky and Provancha 1992 ). Other effects from construction activities would be
noise, construction lighting, and the potential for a nest to be crushed if missed by the state biologists or
volunteer turtle watch patrols.
Noise criteria for sea turtles , as well as other species , have been somewhat formalized between NMFS and
the US Navy. To replace regulatory uncertain ty with scientific facts, NOAA convened a panel in 2004 to
develop noise exposure criteria for fishes and sea turtles. When NOAA’s support ended in 2006, a Working
Group was established to determine broadly applicable sound exposure guidelines for fishes and sea
turtles under the support of ANSI -Accredited Standards Committee S3/SC 1, Animal Bioacous tics, which is
supported by the A coustical Society of America .
Although Level A (205 dB re 1 µPa2·sec) and Level B (182 dB re 1 µPa2·sec) criteria for sea turtle harassment
have been considered by NMFS and the US Navy for explosions associated with certain ordnance disposal
training operations, interim criteria have been developed by NMFS for pile driving , mainly on the West Coast.
However, little data are available on the hearing abilities of sea turtles, their uses of sounds, or their
vulnerabilities (Popper et al 2014). While some researchers have suggested that marine mammals should be
used as the analog for sea-turtle responses to noise, the view of the Wo rking Group is that fishes are more
appropriate due to dissimilar functions of the marine mammal cochlea and the basilar papilla in the ear of
sea turtles (Popper et al 2014). Broadband sound with many frequencies is generated from dredge activities.
While loggerheads are the sea turtle most likely to be encountered during project operations (dredge or
beach) and may possibly suffer mortality due to the encounter, for context and scale it is important to
understand other ongoing and contemporaneous practic es to which significant loggerhead mortality is
attributed. Bolten et al (2011) estimated that two fisheries practices , in particular, each contribute s
10,000–100,000 annual deaths to mostly juvenile loggerheads: pelagic longlines (oceanic juvenile
mortality) and bottom trawls (neriti c juvenile mortality).
Bolten et al (2011) also estimate d that annual shrimp trawl mortality to neritic loggerhead juveniles in the
Gulf of Mexico and the South Atlantic ranged from 6,680 to 162,419 prior to the larger TED op enings imple-
mented in 2003; since 2003, the range is estimated to be 1,221 –8,498 annually. However, they also suggest
that non-compliance, suboptimal TED designs (eg – soft TEDs), and trynets likely contribute to mortality
beyond the 8,498 upper value (Bolten et al 2011). When non-shrimp bottom trawls are included (eg – blue
crab, whelk, scallop), Bolten et al (2011) estimate d annual mortality of juvenile and adult loggerheads
combined to exceed 10,000.
For turtle activities onshore, mu ch research links d ecreased sea-turtle nesting in areas with human
activity, disruptions to hatchling ability to orient, and increased hatchling predation caused by high light
levels compared to natural beaches (Witherington 1992, Kikukawa et al 1999, Witherington and Martin
2000). Although nest relocations in the proposed project area already occur somewhat regularly due to
the narrow eroding beach, relocations as a result of the proposed project construction would be another
direct effect. Dredging itself, the noise associated with dredging and piping, and the concomitant

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increased turbidity in the borrow area waters could also present adverse effects to sea turtles. While
monitoring requirements and procedures prior to and during dredging make it unlikely, potential
entrainment of a turtle by the dredge operation could also be a direct effect.
As part of the standard , beach-nourishment harm reduction/mitigation practices, authorized person nel
conduct daily patrols and remain vigilant for evidence of sea turtle crawls, nests, or turtles on the beach
and for turtles in the vicinity of the dredge operations during the entire project activity. All sea -turtle nests
found ahead of construction w ould be relocated to safer and more appropriate locations, and beach or
dredge operations would cease until the turtle nest (or turtle in the water) is out of harm’s way. Any
relocations would follow all USFWS/NCWRC guidelines and protocols. During the 2011 Nags Head project,
four turtle nests were re located with a success rate of over 85 percent (CSE 2012). If the recent trend of
increased number of sea turtle nests in the Cape Hatteras National Seashore continues into 20 22, it is likely
that more nests may need relocation than during previous nourishment projects (Figure 6.3).
As described elsewhere, lack of safe harbors in the proposed project area results in preference for a sum -
mer dredging window. Therefore, the proposed project poses a higher threat to sea turtles because the
sand placement would occur during nesting season , w hich runs from May through September. Daily turtle
patrols during construction would limit and minimize adverse effects to these species.

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FIGURE 6.3. Number and trend of loggerhead and green sea turtle nests by year
(2000–2020) at the Seashore, and the low numbers of Kemp’s ridley turtle nests statewide.
(Sources: www.seaturtle.o rg on 8 November 2020 and NWRC).

0
100
200
300
400
500
200020012002200320042005200620072008200920102011201220132014201520162017201820192020Number of loggerhead sea turtle nests by
year at Cape Hatteras National Seashore
2000-2020
0
5
10
15
20
25
30
35
Green sea turtle nests at Cape Hatteras
National Seashore 2000-2020
0
2
4
6
8
10
12
2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020
Kemp's ridley sea turtle nests in
North Carolina 2010-2020

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The proposed project also may have indirect effects on sea -turtle nesting h abitat, which could include
changes in beach morphology or sediment characteristics. Changes in beach morphology could result in
less preferred nest sites , and changes in sand characteristics (higher mineral content or color change) can
cause a temperatur e change in the nest known to affect the sex ratios of hatchlings. Suitable sand size
and color and measures to avoid disturbance of sea turtles during dredging and sand placement will help
minimize effects. One beneficial direct effect for this species would include the potential for increased
habitat suitable for nesting due to the wider beach.
Although known turtle nests are protected with staked perimeter and signage, and incubating nests and
hatchlings are monitored and protected, a wider beach may also promote increased use of the beach by
pedestrians and pets. Under this scenario, the potential that a turtle is disrupted from nesting or that a
nest or hatchling is disturbed also increase s.
The proposed project construction may temporarily adversel y affect turtles during the short-term,
although it is likely to have a longer -term, beneficial effect post-construction as potential turtle nesting
habitat is likely to expand from a wider beach. The addition of appropriate sand from Borrow Area 3A and
4 similar in color and grain size is expected. The addition of sand in the nearshore environment replaces
sand lost as a result of natural processes of the eroding beach . This would reduce this beach’s
susceptibility to a breach in the near future, enhanc e its resilience, and help sustain its biological integrity.
While construction of a wider beach in more developed coastal regions of North Carolina may cause an
increase in summer rentals with a concomitant increase in nigh t lighting, the majority of the proposed
project would occur in the already highly developed portion of Dare County. Following nourishment, the
restored beach profile and width would provide improved habitat for sea -turtle nest laying. Th e southern
end of the project area will also be w ider; a wider beachfront may spur an increase in house rentals which
would increase the presence of nighttime lights and nighttime beach walkers.
Encounters with live turtles on the beach or relocated turtles captured in the protection trawl ahead of
dredge operations could be construed as both detrimental and beneficial. It would be detrimental in that
the individual turtle is disturbed or may be injured during the relocation (a non -lethal take). It would be
beneficial in that those turtles will be tagged for scientific study. T agged turtles can be monitored by sea
turtle biologists to expand the understanding of sea turtle behavior and help to improve recovery and
management efforts.
Differences in Direct and Indirect Effects
The difference between the potential effects on these five sea turtle species is based on the extent to which
the species is likely to be present during the proposed activity. Species presence and potential effects are
closely related to nesting with the leatherback, Kemp’s ridley , and green sea turtles being infrequent
nesters , while the hawksbill has never been known to nest in North Carolina until two nests were
documented in 2015 (NPS 2015 d). Of the five sea turtles, the loggerhead is the species most likely to be
affected by the proposed project .

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Kemp’s Ridley Sea Turtle — Of the sea turtles that commonly or occasionally nest in North Carolina, the
Kemp’s ridley is the rarest and is unlikely to nest on eroding or steep beaches, characteristics of the central
section of the p roposed nourishment area. Kemp’s ridley is primarily a tropical to subtropical nesting
species, although seven nests have been documented in North Carolina since 2010, and the Seashore
documented its first Kemp’s ridley nest in 2011 (Randy Swilling, Natural Resource Program Manager, Cape
Hatteras National Seashore, pers comm, 10 April 2015). Two nests were reported within the Buxton sand
placement footprint in 2018 (Source NPS –See Appendix E). Though found rarely, the use of North Carolina
beaches by th is species seems to be on the increase, so the potential exists for it to come ashore in the
proposed project area or to be in the waters in the vicinity of the dredge and pipeline.
Leatherback Sea Turtle — The leatherback is also a rare nester in North Ca rolina and especially rare in the
northern part of North Carolina. Although loggerhead, green, and Kemp’s ridley sea turtles are commonly
found in beach strandings along the Seashore and elsewhere, leatherbacks strand more rarely. Nine nests
have been documented in North Carolina since 2010, one of which was in the Seashore in 2012, but no
nests have been documented in North Carolina in the past four years. One leatherback nest was docu -
mented in the 53-mile-long N.E.S.T. corridor in 2009 and none since. This species is less likely to be
impacted by either dredge or sand placement activities than loggerheads or green sea turtles. Per project-
specific USFWS/NCWRC guidance, nest surveys for leatherback may be required to begin 15 April since this
species may nest earlier than May.
Green Sea Turtle — The green sea turtle is essentially a tropical species and does not generally breed in
temperate zones, but it does occasionally nest on NC beaches and occurs in NC waters during the warmer
months where it feeds on seagrass in the sounds. Green sea turtles have nested in the Seashore every year
since 2006, but represent only ~4 percent of the total sea turtle nests. Highest nest numbers occurred in
2019 (32) and 2013 (23). While nesting appears to be on the in crease, green sea turtles account for nearly
70 percent of the strandings found for all species in the Seashore (Table 6.4). Over the past ten years (2011-
2020) there have been 118 nests recorded in the Seashore (Figure 6.3). Individual green sea turtles may be
impacted in the water during dredg ing or on the beach during sand -placement activity.
Loggerhead Sea Turtle — The loggerhead sea turtle is well adapted to the highly dynamic environment of
the Outer Banks and since 1998 has been the most common sea turtle to strand in the northern Outer
Banks. The most common marine turtle nesting in North Carolina , the average number of nests per year
is around 750 (Godfrey 2013). From 2010 through 2016, 4,694 loggerhead nests were documented in North
Carolina, w ith 1,449 of them along the Seashore in that period and 148 of them in the northern Outer Banks
N.E.S .T. corridor (www.seaturtle.org). While tagging data has been used most exten sively to predict popu-
lation numbe rs for marine sea turtles, satellite telemetry of a southwest Florida loggerhead rookery im -
proved measurements of site fidelity (philopatry) and revealed a need to recalculate fecundity estimates
(Tucker 20 10). If clutch frequency numbers are representat ive of the Western Atlantic population of this
species, then confidence bounds on the estimated breeding stock could be under estimated by as much as
32 percent (Tucker 20 10). As Figure 6.3 shows, the number of loggerhead nests in the Cape Hatteras
National Seashore has increased significantly since 2000, with a record of almost 450 nests in 2019. Nests

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TABLE 6.4. Sea turtle strandings annual total by species at Cape Hatteras National Seashore (2014 -2019 reports and pers
comm. Cape Hatteras National Seashore, Paul Doshkov, Supervisory Biological Technician, 11 November 2020) and Hatteras
Island from 2014-18 November 2020 from www.seaturtle.org.
have been laid along virtually the entire length of the project area in recent years according to NPS
observers (Figures 6.4 and 6.5) (NPS, Paul Doshkov, Supervisory Biological Technician, pers comm 18
March 2021). The proposed project is most likely to impact the loggerhead sea tu rtle, the most common
nester in North Carolina, with either dredge or sand -placement activity.
Hawksbill Sea Turtle — Although four hawksbill sea turtle strandings were documented along the Seashore
between 1996 and 2006 (NPS 2007), no strandings of this spec ies were documented from 2009 to 2016 in
the Cape Hatteras National Seashore (NPS 2015d, 2016a). Two nests were documented along the Seashore
in 2015 for the first time; both were located close to the Proposed Action Area and involved the same turtle
based on genetic analysis (NPS 2015d). According to www.seaturtle.org , there have been no further nests
or strandings of hawksb ill sea turtles since 2015 on Hatteras Island. While it is possible for a hawksbill sea
turtle to occur in North Carolina waters , the proposed project is expected to have no effect on nesting
females, due to its rarity of regular occurrence in the state . Among sea-turtle species with the potential to
occur, hawksbill individuals are the least likely to be encountered.

Year Stranding
Total Loggerhead Kemp’s
Ridley Green Leatherback Hawksbill Unk.
Cape Hatteras National Seashore
2014 219 50 61 104 1 0 3
2015 286 44 39 198 3 0 2
2016 637 45 49 541 1 0 1
2017 280 56 53 168 1 0 2
2018 156 42 41 69 1 0 3
2019 137 31 14 91 1 0 0
1715 268 257 1,171 8 0 11
Hatteras Island total (includes CAHA numbers through 2019 and most of 2020)
2014 258 31 76 148 1 0 2
2015 254 37 40 174 3 0 0
2016 1057 57 45 954 1 0 0
2017 365 52 62 247 2 0 2
2018 126 37 28 59 1 0 1
2019 230 29 21 176 0 0 4
2020* 229 17 20 192 0 0 0
2,519 260 292 1,950 8 0 9
* not complete data for year

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FIGURE 6.4. Loggerhead sea turtle nests and locations recorded along the Village of Avon nourishment area from 2010
to 2020. [Source: Cape Hatteras National Seashore, Paul Doshkov, Supervisory Biological Technician, pers. comm. 18
March 2021].

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FIGURE 6.5. Loggerhead sea turtle nesting history for 2010 -2020 in the Avon sand placement
footprint (Cape Hatteras National Seashore, Paul Doshkov, Supervisory Biological Technician, pers.
comm. 18 March 2021). Note: numbers differ from Fig 7.9 because the northernmos t ~0.9 miles of
Avon is outside the proposed sand placement area. Note: numbers differ from Figure 6.4 because
the northernmost ~0.9 miles of Avon is outside the proposed sand placement area.

Cumulative Effects
Climate change directly affects the reproduction of sea turtles in numerous ways: (1) sea -level rise may
affect significant nesting beach areas on low -level sand beaches and affect back barrier foraging habitat;
(2) higher temperatures increase the chance that sand temperature will exceed the upper limit for egg
incubation of 34°C; (3) higher water temperatures drive prey into new areas which may increase human
encounters (inshore and offshore); and (4) higher nest temperatures bias the sex ratio toward females
because incubation temperature determines the sex of the egg. Owing to high temperatures , loggerhead
turtle nests in Florida are already producing 90 percent females , and if warming raises temperatures by an
additional 1°C or more, no males will be produced there.
Adult feeding patterns are also affected by climate change. Seagrass beds are in decline, water tempera -
ture is higher on intertidal se a grass flats, and coral reefs (typically feeding grounds for green turt les) are
affected by bleaching. Sea turtles have existed for more than 100 million years and have survived ice ages,
sea-level fluctuations of >100 meters (330 ft), and major changes to the continents and the seas. As a
result, they may be able to respon d to unfavorable nesting temperatures or inundation of beaches by seek -
ing out new nesting sites or modifying the seasonality of nesting. It may however take decades or centuries
for sea turtles to re -establish and stabilize their habitats . Steadily encr oaching human development of
coastal areas makes the availability of new habitat for them very limited.
Coastal development will continue to expand, increasing the number of buildings and roads that are
lighted at night, which may adversely affect nesting and hatching sea turtles. With more development
more residents and tourists arrive, which increase s recreational use of the beach in the proposed project
area and beyond. Increased use of the beach by both beach goers and their pets may contribute to the
increased disturbance of nesting sea turtles and turtle hatchlings in the area.
0
2
4
6
8
10
12
14
16
18
20
2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020Number of NestsEvent Year
Loggerhead Sea Turtle Nesting History
Avon Nourishment Project Area

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Interrelated and Interdependent Actions — No interrelated and interdependent actions are associated with
the proposed project; therefore, there are no anticipated adverse effe cts to sea turtles from such actions.
Determination — Minimization measures followed by the National Park Service (all nests will be relocated
prior to construction) and adherence by the dredge contractor to the required 2020 SARBO PDCs during the
project would minimize the likelihood of lethal take on the beach and in the nearshore waters; however,
there is a likelihood that an incidental take could occur (especially for the loggerhead). The 2020 SARBO final
NMFS determination for four of the five sea turtles addressed in this document was Likely to Adversely
Affect while a Not Likely to Adversely Affect determination was included for the hawksbill . The USACE
would initiate formal Section 7 consultation with USFWS for nesting sea turtles and the 2020 SARB O from
NMFS is expected to be utilized for any sea turtle take which may occur in nearshore waters. The National
Park Service would issue a Special Use Permit subject to issuance of the USACE permit for the project .
6.4.3.3 Evaluated Critical Habitat and Effects Determination (Sea Turtles & Atlantic Sturgeon)
Designated critical habitat for the loggerhead sea turtle , the “Constricted Migratory Corridor Critical
Habitat”, potentially traverses through the proposed offshore project area . Recent telemetric tracking of
juvenile loggerheads indicate s that the life history of sea turtles is likely more complex than previously
understood (Mansfield et al 2009, McClellan and Read 2007). Largely as a result of such tracking,
“Constricted Migratory Corridor Criti cal Habitat ” for the northwest Atlantic Ocean logger head turtle DPS
was designated by f inal rule in July 2014 . This habitat is designated primarily because of its high use and
constricted narrow width (land to west and Gulf Stream to east). The corridor is used by juvenile and adult
loggerheads migrating between nesting, breeding, and foraging areas . Because of such high use and
narrowness, the species is more subject to perturbation.
Dredging and sand placement activities could present obstructions to loggerhead turtles in transit through
either the surf zone or the offshore borrow area. But as stated in the final rule (CFR # 15725 on 7.10.2014,
Comments on Constricted Migratory Corridors , response to Comment 73), “…many of the possible impacts
associated with dredging and or disposal activities are not expected to occur, or to occur at a level that would
affect or modify the essential features of the critical habitat.” Additional conservation measures to avoid
impacts to this designated corridor are n ot likely beyond those measures that are typical for projects of
this type and which would be in place to protect the species itself.
There are 17 proposed critical habitat units for the Atlantic sturgeon in southeast US rivers, five of which
occur in North Carolina (C1 -Roanoke River, C2 -Tar Pamlico River, C3-Neuse River, C4 -Cape Fear River and
Northeast Cape Fear River, and CU1 -Cape Fear River). None of these designated critical habitats are within
the project area, and none of these habitats will be affe cted by the project activities. However, Atlantic
sturgeon on their way to or from any of these North Carolina rivers could be in the project area during the
offshore dredging activities.
Interrelated and Interdependent Actions — No interrelated and interdependent actions are associated
with this project; therefore, there are no anticipated adverse effects to critical habitat from such actions.
Determination — Effects are considered insignificant; therefore, no critical habitat for any species
will be adversely affected by the proposed project.

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6.4.4 EFH Species or Complexes Considered
The Magnuson-Stevens Fishery Conservation and Management Act (MSFCMA) defines EFH as “all waters
and substrates necessary to fish for spawning, breeding, feeding, or grow th to maturity” and may include
habitat for individual species or an assemblage of species so designated by regional fishery management
councils. The MSFCMA also requires these regional councils to develop a Fishery Management Plan (FMP)
for each resource or species and to identify any Habitat Areas of Particular Concern (HAPC) within an EFH;
the FMPs are periodically amended. The stated intent of the EFH provisions in the MSFCMA is that EFH
reflect only the important habitats and not the entire range of a species or assemblage (NMFS 2017). Not
only must any HAPC be within an EFH, the HAPC must meet one of four criteria based on either ecological
function, habitat sensitivity to human degradation, human development activities stresses, or rarity.
The FMP amendments of SAFMC and MAFMC identify numerous types of EFH and locations of HAPC, which
are listed in Table 6.5. Table 6.6 shows life stages for those fish species managed by SAFMC/MAFMC and
their association with the categories of Table 6.5 EFH and HA PC that occur in the project vicinity.
On a state level, as mandated by a 1997 state law, the North Carolina Marine Fisheries, Environmental
Management, and Coastal Resources commissions adopted the North Carolina Coastal Habitat Protection
Plan (CHPP) in December 2004 and published the document in January 2 005 (Street et al 2005). The
purpose of the CHPP was long -term enhancement of coastal fisheries associated with coastal habitats. It
provided a framework to protect and restore habitats deemed critical to North Carolina coastal fisheries
updated on a five-year basis. The most current CHPP was published in August 2016 (NCDEQ 2016). The
CHPP identifies six types of these habitats: shell bottom, sea grasses, wetlands, hard bottoms, soft
bottoms, and the water column; these six habitats also occur within, or overlap, some EFH habitats.
While all the EFH types occur in waters of the southeastern United States, and many occur in North
Carolina waters, only a few occur in the immediate project vicinity (wit hin 2 miles) or the project area itself
(maximum footprint of sand placement area = ~100 acres; maximum footprint of Borrow Area and pipeline
distribution area = ~250 acres; combined footprint of project area = ~350 acres). The entire ~330-acre
project area includes the dry beach, intertidal and subtidal surf zone, inshore area, and the entire marine
water column over the borrow area and the fill placement area along the intertidal beach.
Table 6.5 shows the categories of EFH and EFH/HAPC for manag ed species that were identified in the
applicable FMP or Amendments. In general, EFH/HAPC include high value intertidal and estuarine habitats,
offshore areas of high habitat value or vertical relief, and habitats used for migration, spawning, and
rearing of fish and shellfish. Due to characteristics of the proposed maintenance project location/vicinity
where only estuarine and marine environments occur, palustrine and freshwater EFH are not included in
other tables or in additional analyses.

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EFH TYPES BY REGIME GEOGRAPHICALLY DEFINED EFH -HAPC
Palustrine Areas Area - Wide
Unconsolidated bottom/aquatic beds
Tidal forest
Tidal freshwater
Sargassum habitat (pelagic and benthic)
Hard bottoms
Hoyt Hills
State-designated areas of importance
All coastal inlets
Hermatypic coral habitat and reefs
Council-designated Artificial Reef Special
Management Zones (SMZ)

Estuarine Areas
Subtidal/intertidal non -vegetated flats
Emergent wetlands
Estuarine scrub / shrub (mangroves)
Water column
State-designated PNAs and SNAs
Unconsolidated bottom
Oyster reefs and shell banks
Submerged aquatic vegetation (SAV)
Coastal inlets
High salinity bays, estuaries, and seagrass habitat

North Carolina
Bogue Sound
Pamlico Sound at Hatteras/Ocra coke islands
New River
The Ten Fathom Ledge
Big Rock
Sandy shoals at capes (Hatteras, Lookout, Fear)
The Point
Primary and Secondary Nursery Areas
Cape Lookout South Spawning SMZ

Marine Areas
Unconsolidated bottom/aquatic be ds
Artificial / manmade reefs
Coral reefs
Live/hard bottom
Sargassum
Water column
Emergent wetlands
Submerged aquatic vegetation (SAV)
Continental shelf currents/Gulf Stream
Ocean high salinity surf zones
Sandy shoals of capes and offshore bars
Coastal inlets
Offshore habitats used for spawning & growth to maturity

Table 6.5 Notes: EFH identified in FMP Amendments for SAFMC and MAFMC. Geographically defined HAPC are identified in FMP Amendments affecting the south Atlantic area. The EFH for species managed under NMFS Billfish and Highly Migratory Species generally falls within the marine and estuarine water column habitats designated by the Councils. Information in this table w as derived from Appendices 4 and 5 of NMFS 2010 and SAFMC EFH and HAPC designations from https://safmc.net/wp-content/uploads/2016/06/EFH20Table.pdf and https://safmc.net/wp-content/uploads/2016/06/EFH-HAPC20Table.pdf

TABLE 6.5. Types of Essential Fish Habitat (EFH) by water re gime and EFHHAPC defined in the south Atlantic region and in
North Carolina.

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Table 6.6 lists the federally managed fish species for which Fish ery Management Plans (FMPs) have been
developed by the South Atlantic Fishery Management Council (SAFMC) and/or the Mid -Atlantic Fishery
Management Council (MAFMC) and which may occur in the project area waters or vicinity. In addition, the
table shows EFH by fish life stage category for those species that have designated EFH. Fish species which
utilize habitats shown in Table 6.5 and occur in the water bodies of NC shown in Table 6.6 require special
consideration to promote their viability and sustainabil ity.
The habitats and HAPC for species managed by the Atlantic States Fishery Management Council (ASFMC)
and EFH and HAPC for SAFMC -managed species are shown in Table 6.7 along with the species for which a
FMP has been developed and the species with ASFMC strategies and management goals. The management
history for Highly Migratory Species is shown in Table 6.8. The potential effects of the proposed project on
species and habitats are summarized in Table 6.9 ; for the purposes of this analysis, project vici nity is within
2 miles and the project footprint includes the dredged borrow area, the pipeline footprint, staging area
footprint on the beach, and the sediment placement area.
Figure 6.6 shows the hard bottom, possible hard bottom, shipwrecks, and artif icial reefs in state and federal
waters of the North Carolina coast in the vicinity of Cape Hatteras as depicted in NCDEQ (2016), the most
recent version of North Carolina’s Coastal Habitat Protection Pl an. The small black square south of Buxton
indicated as “hard bottom – point” from the Moser Taylor 1995 data represents the existing groins installed in
the 1970s under the direction of the US Navy to protect a facility adjacent to Cape Hatteras Lighthouse and to
hold sand along the beach around the lighth ouse. This habitat is ~4.5 miles south of the Avon project area.
Geotechnical studies of the proposed borrow area including ~12 borings 10 ft long and over a dozen
additional in and around the area to ~7 ft, and geophysical surveys for the project by TA R confirm there is
no hard bottom in the borrow area (Appendix G – Cultural Resources Study). Previous surveys conducted
or reviewed as part of the NOAA Southeast Area Monitoring and Assessment Program (SEAMAP) indicate
that the nearest offshore hardbotto m habitat is ~13 miles southeast of the proposed project area. The
cultural resources surveys by TAR confirm by remote sensing (ie – shallow seismic, magnetometer and side
scan surveys) that no significant cultural resources such as wrecks and their associ ated habitat occur
within the proposed Avon borrow area . All interim and final survey data will be coordinated and provided
to representatives of the NMFS and North Carolina Division of Marine Fisheries (NCDMF) (See Appendix G).
Current NC Coastal Resou rce Commission (CRC) rules discourage dredging activities within a 1,640 -foot
buffer of significant biological communities, such as high relief hard bottom areas [T15A NCAC 07H
.0208(b)(12)(A)(iv)]. Under this rule, “high relief” is d efined as greater than or equal to ~1.7 -feet per ~16
feet of horizontal distance. Because reef fishes derive a significant portion of their nutritional requirements
within a 500 m “halo” of exposed hard bott om Lindquist et al (1994), this sand dredging buffer was
recommended by the NCDCM-appointed Ocean Policy Steering Committee around hard bottom areas,
including those periodically buried with thin, ephemeral sand layers (NCDCM 2009). No hardbottom
features, or significant cultural resources have been identified within the pr oject area. See Appendix G.

TABLE 6.6. Life stage categories for managed species by geographic region within the Project Area or near vicinity (as shown on
NOAA/NMFS EFH mapper, depicted in figures of Fin al Amendment 10 to 2006 consolidated HMS, or described in various
management amendments). For some species, paucity of information results in all life stages combined into the ALL category.
Note: — = life stage category not shown on EFH mapper; N = speci es not shown on EFH mapper for this life stage category; Y =
species shown on EFH mapper for this life stage category. Some species with no life stage categories shown as EFH in the pro ject
area are included in table due to EFH in proximity and footnoted at the bottom of the table.
.

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TABLE 6.7. EFH type and EFH/ HAPC within the project vicinity or project footprint for which potential impacts may occur.
Includes ASFMC-managed species and SAFMC EFH or EFH/HAPC (as shown in Ta ble 6.5) and the protected resource designated to
that habitat under a fishery management plan (FMP) developed for each protected resource. Updated from SAFMC (2020)
http://safmc.net/download/SAFMCEFHUsersGuideFinalNov20.pdf
(* indicates ASMFC habitat, A SMFC EFH-HAPC, or SAFMC EFH; ** indicates SAFMC EFH -HAPC).
Eggs Larvae
Spawning,
eggs &
larvae
Neonate Neonate/
YOY Juvenile Adult ALL
Common name Latin name
*Atlantic butterfish Peprilus triacanthus N N ———Y Y
*Atlantic mackerel a Scomber scrombus N N ———N N
*Bluefish Pomatomus saltatrix N N ———Y Y
*Longfin inshore squid b Doryteuthis (Amerigo) pealeii N ————N N
*Scup Stenotomus chrysops N N ———Y Y
*Spiny dogfish Squalus acanthias —————N Y
*Summer flounder Paralichthys dentatus N Y ———Y Y
Spiny lobster Panulirus argus ———————Y
Snapper Grouper ———————Y
**Coastal migratory pelagics ———————Y
Albacore tuna Thunnus alalunga —————Y N
Bluefin tuna Thunnus thynnus ——Y ——Y Y
Yellowfin tuna Thunnus albacares ——N ——Y Y
Atlantic sailfish Istiophorus platypterus ——N ——Y Y
Blacktip shark Carcharhinus limbatus ———N —Y Y
**Sandbar shark Carcharhinus plumbeus ———Y Y Y Y
Scalloped hammerhead shark Sphyrna lewini ———N N Y Y
Spinner shark Carcharhinus brevipinna ————Y Y Y
Tiger shark Galeocerdo cuvier ———Y Y Y Y
Common thresher shark Alopias vulpinus ———————Y
Atlantic angel shark Squatina dumerii ———————Y
Dusky shark c Carcharhinus obscurus ————Y Y Y
Sand tiger shark Carcharias taurus ———Y Y Y Y
Smooth dogfish Mustelus canis ———————Y
Atlantic sharpnose shark Rhizoprionodon terraenovae ———Y Y Y Y
Blacknose shark Carcharhinus acronotus —————Y Y
a EFH for juveniles to Cape Hatteras; mostly north of 38° according to MAFMC Amendment 11 * indicates species managed by MAFMC
b EFH for adults includes Hatteras Inlet ** indicates EFH/HAPC within project area
c EFH Amendment 10 appears to not include Cape Hatteras when zoomed
Greater Atlantic region
Mid-Atlantic species
South Atlantic region (SAFMC)
Life stage category
Managed species and geographic region
Smoothhound shark complex (NMFS)
Small coastal sharks (NMFS)
Highly migratory species (NMFS)
Billfish (NMFS)
Large coastal sharks (NMFS)
Pelagic sharks (NMFS)
Prohibited sharks (NMFS)
https://www.habitat.noaa.gov/application/efhmapper/index.html
.

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HABITAT TYPE FMP ASMFC
Unconsolidated botto m* Red drum, snapper grouper,
spiny lobster1
Red drum, horseshoe crab, scup,
spiny dogfish, summer flounder

Offshore marine habitats used for
spawning and growth to maturity* Shrimp, snapper grouper
Atlantic menhaden, Atlantic
striped bass, Atlantic sturgeon,
bluefish, alewife, American shad,
blueback herring, hickory shad,
Spanish mackerel, spiny dogfish,
spot, spotted seatrout, weakfish,
Atlantic coastal sharks
Ocean high salinity surf zones* Red drum, coastal migratory
pelagics
Red drum, Atlantic striped bass,
bluefish, spotted seatrout,
Atlantic coastal sharks

Spawning area in the water column
above the adult habitat and the
additional pelagic environment,
including Sargassum; Sargasso Sea*

Snapper grouper, coastal
migratory pelagics American eel

Barrier island ocean side waters from
the surf to shelf break zone but
shoreward of the Gulf Stream*

Coastal migratory pelagics

Horseshoe crab

Shallow subtidal bottom*

Spiny lobster1 Horseshoe crab, scup

Pelagic sargassum habitat** (windrows
in nearshore project vicinity)**

For dolphin under coastal
migratory pelagics American eel, cobia
Sandy shoals of Cape Hatteras from
shore to the ends, but shoreward of the
Gulf Stream**

Coastal migratory pelagics Red drum, horseshoe crab, scup,
bluefish, summer flounder
1 not usually found north of southern North Carolina coast

TABLE 6.8. Management history of designated EFH for highly migratory species (HMS). (Table 3.1 from NOAA 2017; updated).

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FMP or Amendment EFH and Species
1999 FMP for Atlantic tuna,
swordfish, and sharks
EFH first identified and described for Atlantic tunas, swordfish and
sharks; HAPCS designated for sandbar sharks
1999 Amendment 1 to the 1988
Billfish FMP EFH first identified and described for Atlantic billfishes
2003 Amendment 1 to the FMP for
Atlantic tunas, swordfish and sharks
EFH updated for five shark species (blacktip, sandbar, fin etooth, dusky,
and nurse sharks)
2006 Consolidated Atlantic HMS FMP
Comprehensive review of EFH for all HMS. EFH for all Atlantic HMS
consolidated into one FMP; no changes to EFH descriptions or
boundaries
2009 Amendment 1 to the 2006
Consolidated Atlantic HMS FMP
EFH updated for all federally managed Atlantic HMS. HAPC for bluefin
tuna spawning area designated in Gulf of Mexico
2010 Amendment 3 to the 2006
Consolidated Atlantic HMS FMP
EFH first defined for smoothhound sharks (smooth dogfish, Florida
smoothhound, and Gulf smoothhound)
2010 White Marlin/Roundscale
Spearfish Interpretive Rule and Final
Action
EFH first defined for roundscale spearfish (same as white marlin EFH
designation in Amendment 1 to 2006 Consolidated Atlantic HMS FMP)
2015 Atlantic HMS EFH 5-Year Review Comprehensive review of EFH for all HMS. Determined that changes to
some EFH descriptions and boundaries were warranted.
2016 Draft Amendment 10 to the 2006
Consolidated Atlantic HMS FMP
Presents alternatives th at would update EFH for all federally managed
Atlantic HMS. Existing HAPCs for sandbar shark and bluefin tuna would
be adjusted, and new HAPCs for sand tiger shark and lemon shark would
be created to reflect recommendations in the 5 -year review
2017 Final Amendment 10 to the 2006
Consolidated Atlantic HMS FMP
Public comment period ended 22 December 2016. Final amendment
approved 30 August 2017 and published in Federal Register on 7
September 2017

2019 Final Amendment 11 to the 2006
Consolidated Atlantic HMS FMP
Public comment period ended 1 October 2018 and Final became
effective 3 March 2019. Included management measures to address
overfishing and rebuild stock of North Atlantic shortfin mako shark
2020 Draft Amendment 12 to the 2006
Consolidated Atlantic HMS FMP
Announced 23 June 2020 integrates provisions of recently revised
National Standard guidelines, a standardized bycatch reporting
methodology rulemaking, and NOAA Fisheries policy directives . Public
comment closed 26 October 2020.

TABLE 6.9. EFH categories and geographically defined HAPCs within project vicinity or area and potential impacts of proposed
project by activity (Y = yes; N = no; W =within acceptable limits). Refer to Appendix F‒Essential Fish Habitat Assessment for details.

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PROXIMITY IMPACT ACTIVITY
ESSENTIAL FISH HABITAT Project
Vicinity
Project
Impact Area
Dredge
Operation
Sand
Placement
Estuarine
Emergent wetlands Y N N N
Estuarine scrub/shrub mangroves N N N N
Submerged aquatic vegetation (SAV) Y N N N
Oyster re efs and shell banks Y N N N
Intertidal flats Y N N N
Aquatic beds N N N N
Estuarine water column Y N N N
Seagrass Y N N N
Creeks N N N N
Mud bottom N N N N
Marine
Emergent wetlands Y N N N
Unconsolidated/shallow subtidal bottom Y Y Y Y
Live/hard bottoms N N N N
Coral and coral reefs N N N N
Artificial/man-made reefs N N N N
Sargassum Y Y W N
Water column & high salinity surf zones 1 Y Y W W
GEOGRAPHICALLY DEFIN ED HAPC
Area-Wide
Council-designated artificial reef Special managemen t zones N N N N
Hermatypic (reef-forming) coral habitat and reefs N N N N
Hard bottoms N N N N
Hoyt Hills N N N N
Sargassum habitat Y Y W N
State-designated areas of importance for managed species (PNAs) N N N N
Submerged aquatic vegetation (SAV) Y N N N
North Carolina
Big Rock N N N N
Bogue Sound N N N N
Pamlico Sound at Hatteras/Ocracoke Islands N N N N
Cape Fear sandy shoals N N N N
Cape Hatteras sandy shoals Y Y W N
Cape Lookout sandy shoals N N N N
New River N N N N
The Ten Fathom Le dge N N N N
The Point N N N N
1 effect is likely to be negligible (eg – project turbidity in surf zone water column would be very temporary and similar conditions
commonly occur naturally and often for longer duration)

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FIGURE 6.6. Location of hard bottom, possible hard bottom, shipwrecks, and artificial reefs in state and federal waters off
North Carolina- northern coast (from NCDEQ 2017, Map 7.1.a). Blue arrow points to Avon Village.

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Areas shown in Fig. 6.7 include EFH-HAPC as follows: The Point (largest green unidentified rectangle) for
Coastal Migratory Pelagics, Coral, Coral Reef, Live/Hard Bottom, Tilefish, Snapper/Grouper, and
Dolphin/Wahoo is located approximately 25 miles offshore from Avon/Cape Point/Cape Hatteras and the
proposed project area; the sand colored narrow polygon south and north of The Point for tilefish; coastal
inlets (blue circles) for Shrimp and Snapper/Grouper, and; the grey, blue, or green colored polygons along
the shores of Pamlico Sound for Primary and Secondary and Permanent Secondary Nursery Areas for
Shrimp and/or Snapper/Grouper. Note: the marsh on the sound side of Hatteras Island in vicinity the
proposed project area contains no EFH -HAPC designated Nursery Areas.

FIGURE 6.7. A screen shot of SAFMC designated EFH-HAPC near proposed project (SAFMC EFH Viewer webpage accessed 15
October 2020) https://www.habitat.noaa.gov/protection/efh/efhmapper/. See text for description of habitats in the various
polygons of this figure.

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6.4.5 Potential EFH or HAPC and Fish Species with Potential Effects
This section expands upon the currently designated EFH or EFH -HAPC with the potential to occur within
the project vicinity (within 2 miles of project area footp rint) or project area (actual project footprint) shown
in Table 6.9. Fish utilization is described in more detail for only those EFH or EFH -HAPC found within the
project area. For a full description of other EFH occurring within the vicinity, see Appendi x F – Essential
Fish Habitat Assessment.
Potential EFH and HAPC in the vicinity not evaluated further (see Appendix E for more details).
 Estuarine Emergent Wetlands – Although this habitat occurs close by on the west side of Hatteras
Island, there is no direct connection with the Proposed Action Area. The closest inlets are ~1 6 and
30 miles away.
 Submerged Aquatic Vegetation (SAV) and Seagrass – The nearest SAV is located in the vicinity
in Pamlico Sound, but not in the project area because of its separati on by Hatteras Island. Figure
6.8 shows the distribution of submerged aquatic vegetation west of the Proposed Action Area.
 Oyster R eef and Shell Banks – This habitat may occur in the vicinity in Pamlico Sound west of
Hatteras Island, but is not present in the project area because of the land barrier separating the
habitat from the Proposed Action Area.
 Estuarine Intertidal Flats – This habitat occurs west of Hatteras Island in Pamlico Sound in the
vicinity of the project, but not within the Proposed Action Area.
 Estuarine Water Column – This important habitat which supports numerous managed species is
in the vicinity of the proposed project, but separated by the land mass, Hatteras Island. The
closest inlet is ~1 6 miles away and therefore it is not evalua ted further.

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FIGURE 6.8. Submerged aquatic vegetation within the project vicinity. See Appendix F – EFH for details on this
habitat in the vicinity of the Proposed Action Area, but physically separated from the project.

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Potential EFH and HAPC that may be Impacted by the Project
Sargassum and Sargassum Pelagic Habitat – Sargassum filipendula is a benthic brown macroalgae
found along the Atlantic coast of the Americas in shallow subtidal zones attache d to rocks or shells, but is
also found in deeper waters of 80 to 100 ft. In North Carolina, this alga occurs predominantly south of
Cape Hatteras often growing on jetties near stabilized inlets. As it has larger floats than other species of
Sargassum and weaker holdfasts, rough weather will often dislocate the holdfasts and it is often carried
out to the open ocean where it joins other species of seaweed and Sargassum in the Sargasso Sea.
Positively buoyant, the larger floats of S. filipendula keep it on top of the large floating mats of seaweed
common to the Sargasso Sea. Of the 150 species worldwide, two other free -floating species of Sargassum
are found in the Atlantic, S nutans and S fluitans with S. nutans the most common.
Sargassum can occur in large floating mats in the waters of the continental shelf, in the Sargasso Sea, and
in the Gulf Stream and can appear as concentrations of small patches (Fig 6.9), large mats, or often miles -
long weed lines, or windrows, along current convergence boundari es in the open or coastal ocean (Deaton
et al 2010, NCDEQ 2016 ). It circulates primarily between 20° and 40° N latitudes and 30° W longitude and
the western edge of the Florida Current/Gulf Stream.
Masses of S argassum provide a mobile structural home fo r over 100 species of fish (mostly larval and
juveniles; left photo Fig 6.9), fungi, and micro- and macro-epiphytes, at least 145 species of invertebrates,
four species of sea turtles, and numerous marine birds. Roughly 2M square miles in area, the Sargas so Sea
is bordered by a ring of four currents; on the north by the North Atlantic Current, on the east by the Canary
Current, on the south by the North Atlantic Equatorial Current, and on the west by the Gulf Stream. These
currents rotate a large eddy in a clockwise circulation (the North Atlantic Central Gyre) and also trap
floating debris and trash/plastics such that the area is known as the North Atlantic Garbage Patch. The
Sargasso Sea receives little wind or rain. The rotation keeps the masses of Sargassum and other seaweed
in the Sargasso Sea from dispersing into other parts of the ocean; although some smaller rafts or windrows
do separate from the larger masses under certain wind and current conditions and drift in the open ocean
(middle photo, Figur e 6.9) or can be driven all the way to shore (right photo, Figure 6.9).
Under certain wind conditions, relatively small masses of Sargassum may wash ashore from the Gulf
Stream or outer continental shelf waters and it can also be found occasionally in near shore waters. Since
2011, beaches of the Caribbean have experienced massive influx es of two species of Sargassum along with
the western equatorial coast of Africa. The source of this new and unpleasant (for tourism) and fatal
(smothered sea turtle nests, fish kills) Caribbean phenomena at first was thought to be the Sargasso Sea
or the Gulf of Mexico but satellite images revealed it to originate from the coast of Brazil transported by
equatorial currents. This recent spate of Sargassum blooms is suspected to be driven by increased
nutrients from the Amazon River (and potentially the Congo River) in addition to potential changes in
water temperature due to climate change, iron rich African dust plumes, or changes in the complex
dynamics of the North Equatori al Recirculation Region (NERR) (Oxenford et al 2015; Louime et al 2017;
University of South Florida 2019; Langin 201 8; McBride 2019 ).

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Pelagic Sargassum species could drift through the Proposed Action Area offshore, or depending on wind
and currents, could drift into the nearshore or surf zone. Because it occurs in the upper few feet of the
water column, it is not subject to direct effects from dredging, although sediment placement activities
associated with the proposed project could introduce temporary t urbidity in the shallow water column
during sand placement. However, this turbidity is short -lived and will likely duplicate storm conditions;
thus, no impacts are expected to this EFH or its associated managed fish species from turbidity.
Juvenile fish or other organisms associated with Sargassum may serve as food for managed fish when
any mats have floated into the nearshore or surf zone; species already in the nearshore/surf zone water
column may also use the mat as refugia. If floating mats are encoun tered during dredging or are washed
ashore during sand placement and are buried, these mats would represent a very small portion of the
total EFH or EFH-HAPC available. Since Sargassum occurs in the upper few feet of the water column
and is not commonly found in the project area, the project is not expected to have any impact on
this EFH or HAPC or the life stages of managed species which utilize them; any impacts that may
occur are expected to be minor and within acceptable limits .
Water Column – the water column is the medium which connects all aquatic habitats, provides a basic
ecological role for all organisms within it, and performs an essential corridor function for species which
depend on more than one habitat for various life stages (Deaton et al 2010; NCDEQ 2016). Either or both
the estuarine and marine water column are EFH for all managed species as shown in Table 6.6. Life stages
of many of the species are found in the nearby estuarine waters of the North Carolina back -barrier sounds
(Roanoke, Paml ico, and Croatan sounds) and/or nearest inlets (Oregon Inlet is ~30 miles to the north and
Hatteras Inlet is ~12 miles to the southwest). Some other managed species can be found in the nearshore
marine waters of the proposed borrow area or in the surf zon e in the vicinity of proposed sand placement.
A project conducted from March 2015 to October 2019 by NOAA’s National Center for Coastal Ocean
Science (NCCOS) developed a calendar of environmental windows which shows the monthly distribution
of sensitive e arly life stages for important fishery species in the Carolinas and which aquatic regime/type
these stages are found (Figure 6.10). The purpose of the project was to provide a guide for coastal resource
managers to reduce and minimize development -related impacts to fisheries. Of direct relevance to the
proposed action, marine water column is the specific habitat that could be potentially affected (addressed
in the following section).

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FIGURE 6.9. Floating mat of Sargassum with associated small fish (courtesy of NOAA Ocean Explorer Gallery),
weedline/windrow of Sargassum (SAFMC website) and drifts on Caribbean island of Tobago in 2015 (Credit:
rjsinenomine (CC BY 2.0)] and monthly Sargassum distribution derived from MERIS satellite imagery from 2002 -2008
(as shown in Oxenford et al 2015).

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FIGURE 6.10. Distribution of sensitive life stages of important fishery species in the Carolinas across the months of the
year by aquatic type/location. (https://coastalscience.noaa.gov/project/fisheries -assessment-to-inform-time-of-year-
restrictions-for-nc-and-sc/)

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Marine Water Column – this broad EFH also includes ocean high salinity surf zones EFH for red drum and
coastal migratory pelagics, barrier island ocean -side waters from surf to shelf break zone and from Gulf
Stream shoreward EFH for coastal migratory pelagics, and spawn ing area above adult habitat and
additional pelagic environment EFH for snapper , grouper, and shrimp under various FMPs. Additionally,
the marine water column is utilized by various life stages of ASMFC species including Atlantic menhaden,
shad, spotted s eatrout, spiny dogfish, and Atlantic coastal sharks among others.
The coastal and nearshore Atlantic Ocean waters of North Carolina occupy a unique location in that the
colder southerly Labrador Current (a portion of the North Atlantic gyre) intersects w ith the warmer
northerly Gulf Stream in the vicinity of Cape Hatteras, which also is a biogeographic boundary and is the
closest point of land to the Gulf Stream along the mid -Atlantic coast (see Appendix F for further
discussion). This collision of curren ts generally reduces the marine water column temperatures north of
Cape Hatteras and increases temperatures south of Cape Hatteras. The collision generates offshore
frontal mixing zones which, combined with the varied winds and shifting bottom topography
characteristic of Cape Hatteras shoals, causes nutrient -rich upwelling. See Figure 6.11 for a general
depiction of marine water column masses around the Proposed Action Area. Appendix F (Essential Fish
Habitat Assessment) discusses the species that utili ze the marine water column around Cape Hatteras.

FIGURE 6.11. Depiction of Cape Hatteras marine water column dynamics .
(https://www.coastalstudiesinstitute.org/rese arch/coastal-engineering/research-
project-processes-driving-exchange-cape-hatteras).

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Dredging and sand placement activities conducted during project construction will occur in the marine
water column in the immediate vicinity of the borrow area and the target beach which h ave the potential
to impact nearshore and intertidal surf zone resources of larval, juvenile, and/or adult life stages. These
impacts may include minor and short -term sediment plumes (and related turbidity) as well as the release
of trace constituents from the sediment into the water column.
Marine sediments can be sinks/reservoirs for various pollutants most typically sourced to atmospheric or
riverine deposition. Trace constituents found in the sediments which may be released into the water
column during dredging or sand placement activities in connection with beach nourishment projects are
usually associated with source sediment having proximity to either an active or old port, wastewater
treatment facilities, effluents from industries, or undocumented s pill of pollutants. Additionally,
important nutrients can accumulate in various soft bottom sediments and be reintroduced into the water
column when disturbed. Although it could possibly contain constituents from an unknown spill, the
proposed Borrow Are a is a naturally formed, sandy high energy shoal located at considerable distance
from a port, inlet, or known effluent source so it is unlikely to release harmful contaminants or nutrients
during dredging or placement activities. The borrow area is regul arly exposed to waves greater than 10 ft
and generally exhibits only trace amounts of fine -grained clays to which contaminants can adsorb.
Other effects from turbidity in the water column would include changes in light penetration and visibility
which may be either beneficial or problematic (whether predator or prey) and can interfere with nutrient
availability for filter -feeders. Because the proposed borrow area consists of >99 percent sandy or shelly
material, settling of sediments placed into suspension during dredging operations is expected to be rapid
and measured in minutes, returning the borrow area to ambient conditions soon after cessation of
operations. The fishes of the ocean high salinity surf zone are adapted to frequent and naturally turbid
habitat conditions; higher turbidities which occur during sand placement operations of the proposed
project will be of shorter duration than many common weather events and be concentrated close to a
single discharge point at any given time during constructio n.
Turbidity in the water column from beach placement of sand may create localized stressful habitat
conditions and may result in the temporary displacement of fish and other biota. Given the high -energy
offshore environment and the coarse sediment compos ition, the turbidity plume created is expected to be
short-lived. Coarse sediments have much higher settling velocities than finer material (Table 6.10). Fine-
grained sediments (such as silts and clays) produce greater and longer lasting turbidity plumes, which can
impact large areas of the sea floor more than coarser, sand -sized material (USACE 2002a). Suspended
sediments settle at predicted rates dependent on grain size as shown in Table 6.10 below. The time
necessary for sediments in the turbidity plume to settle whether in suspension from dredge activity, in the
slurry itself, or resuspended during manipulation is also affected by current and wave climate in the
borrow area during dredge activity and in the intertidal zone during placement and manipulat ion. While
turbidity plumes associated with dredging are often short -lived and may affect relatively small areas,
subsequent resuspension and redispersal of dredged sediments can propagate beyond the dredged area
for extended periods in certain wave climat es (CSA International et al 2010). However, these effects are
minimal in sandier offshore areas such as the high energy shoal of the proposed borrow area.

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ds
(mm)
dv
(mm)
df
(mm)
@ 10°C
(m/sec)
@ 20°C
(m/sec)
*Sand
Classification
0.089 0.10 0.1 0.005 0.007 vf
0.126 0.14 0.14 0.010 0.013 vf-f
0.147 0.17 0.16 0.013 0.016 f
0.208 0.22 0.22 0.023 0.028 f
0.25 0.25 0.25 0.028 0.033 f-m
0.29 0.30 0.29 0.033 0.039 m
0.42 0.46 0.40 0.05 0.058 m
0.59 0.64 0.55 0.077 0.084 c
0.76 0.80 0.70 0.100 0.110 c
1.25 1.40 1.00 0.15 0.160 vc
1.8 1.90 1.20 0.17 0.170 vc

The impacts associated with the proposed project from turbidity are likely to be similar, on a smaller scale,
to the effects of storms. Storm effects also generally include increased turbi dity and suspended sediment
load in the water column and, in some cases, changes in fish community structure (Hackney et al 1996).
Severe storms have been associated with fish kills, but such situations are not associated with beach
disposal of dredged sand. Turbidity will be most noticeable in proximity to the slurry discharged from the
pipe head which operates ahead of the beach building activities. The section of beach affected per day will
vary from 800 to 1,000 ft in length with 300 ft per day as the estimated completion rate. Elevated turbidity
levels were detected within up to ~500 ft down -current of the discharge point along Nags Head during the
2011 project (CSE 2012). The discharge plume was generally not detectable at greater distances.
Van Dolah et al (1994) assessed turbidity conditions associated with a beach nourishment project at Folly
Beach (SC), where native mean grain size is ~0.2 mm, and drew the following conclusion:
Although dredge effluent does increase turbidity levels in the immed iate vicinity of the
outfall, there are many other factors such as local weather and wave energy that will also
produce this effect. The turbidity levels at Folly Beach during nourishment and the dispersal
of the sediment plume were not considered unusual or severe relative to normal fluctuations
and background levels.
As mentioned in USACE (2014) in their Environmental Report on the Use of Federal Offshore Sand
Resources for Beach and Coastal Restoration in New Jersey, Maryland, Delaware and Virginia (MMS 1999),
the U.S. Department of Interior BOEM (previously MMS) provided the following assessment:
TABLE 6.10. Sediment settling velocities. [ds- sieve diameter. dv- volume sphere
diameter. [df- sedimentation diameter. *Wentworth Classification.].

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In order to assess if turbidity causes an impact to the ecosystem, it is essential that the
predicted turbidity levels be evaluated in light of conditions such as during storms. Storms
on the Mid-Atlantic shelf may generate suspended matter concentrations of several hundred
mg/L (e.g., Styles and Glenn 1999). Concentrations in plumes decrease rapidly during
dispersion. Neff (1981, 1985) reported that solids con centrations of 1000 ppm two minutes
after discharge decreased to 10 ppm within one hour. Poopetch (1982) showed that the initial
concentration in the hopper overflow of 3,500 mg/L decreased rapidly to 500 mg/L within 50
m. For this reason, the impact of the settling particles from the turbidity plume is expected
to be minimal beyond the immediate zone of dredging.
Burlas et al (USACE 2001) found that certain fish species (e,g., kingfish) were attracted to higher turbidity
waters, whereas other species (e.g., bluefish) avoided high turbidity water around the discharge pipe
during a major nourishment project along the central New Jersey coast. This study indicates that fish may
seek as well as avoid locally turbid water associated with beach nourishment and th at the presence of
elevated turbidity can repel, or even attract, certain species dependent upon their particular adaptive
behavior. In addition to USACE 2001, other studies have also found insignificant impact or even a
temporary increase in surf zone fi sh populations associated with nourishment projects as possibly
attributed to:
1) release of nutrients and infauna during dredging,
2) wide-foraging nature of surf zone fish, or
3) short term stay of migratory fish in the project area (Deaton et al 2010; NCDEQ 2016).
So while highly migratory managed species such as bigeye, bluefin, skipjack, and yellowfin tuna all have
been documented as juvenile and adults in Hatteras Inlet and presumed to be in the waters near Avon, it
is unlikely these species will be affecte d by the associated turbidity of the proposed project.
Fish larvae in the ocean waters near Oregon Inlet generally travel westward until they encounter the
shoreline then migrate along the shoreline until they encounter the inlet (USACE 2002b). As stated in the
EFH assessment prepared for the Rodanthe project (USACE 2014) larval ingress and egress studies suggest
that larval transport from offshore shelves to estuarine nursery habitats occurs in three stages: offshore
spawning grounds to nearshore, nearsho re to the locality of an inlet or estuary mouth, and from the mouth
into the estuary (Boehlert and Mundy 1988). Re sults from the Hettler and Hare 1998 study suggest two
bottlenecks for offshore -spawning fishes with estuarine juveniles: the transport of la rvae into the
nearshore zone and the transport of larvae into the estuary from the nearshore zone. While the methods
fish larvae use to cover large distances over the open ocean and find the inlets to their estuarine nurseries
is uncertain, both passive a nd active methods of movement are suspected along with use of environmental
cues such as salinity, depth, temperature, swells, etc. Various studies have hypothesized passive wind and
depth-varying current dispersal and active horizontal swimming transport. However, data are limited
regarding larval distribution in the nearshore area. As indicated in USACE (2014), population level

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calculations of larval entrainment from hydraulic dredging activities were insignificant within a
representative high concentra tion inlet bottleneck at Beaufort Inlet, North Carolina. Therefore, the risk of
larval entrainment from dredging activities in the proposed borrow area associated with this project would
likely be even less. However, some larvae in the marine water column adjacent to the beach could be
buried or injured during sand placement activities but not in numbers that would have a long -term effect
at the species level. Diamond Shoals lies between the Avon project area and Hatteras Inlet (the nearest
inlet). Currents and waves associated with these shoals act as a barrier to longshore transport which
naturally converges toward Diamond Shoals (Deaton et al 2010; NCDEQ 2016 ) and therefore likely divert
seaward a component of larvae drifting in the littoral current in the Avon and Buxton vicinity.
For the reasons described above, marine water column EFH including the surf zone EFH will experience
temporary turbidity from both the dredge operation and the sand placement activity along with the
potential for some fish or benthos larval death and/or injury from turbidity; however, mobile juvenile and
adult fish species have the ability to locate away from the most disruptive activities. Noise levels may result
in avoidance behaviors in some mobile fish species but leve ls are not expected to cause hearing damage.
Temporary interruptions to feeding activities of fish that predate on the benthic invertebrates may occur
but these interruptions would be minor since large expanses of similar habitat are nearby. These effects
are not expected to be long lasting or cause significant impact to the marine water column or ocean
high-salinity surf zone EFH or the life stages of managed species found within these habitats .
Hard Bottom – while more than 90 percent of the hard bottom EFH of North Carolina occurs south of Cape
Lookout, numerous occurrences of hard bottom or potential hard bottom exist north of Cape Hatteras.
However, north of Cape Lookout the nearshore hard bottom EFH including shipwrecks often have low
relief which ma kes them ephemeral (a storm may bury or uncover the habitat). The EFH can include both
natural (rock outcrops) and unnatural components (shipwrecks). Pleistocene algal communities account
for the natural hard bottom features (slight ridges, ledges and sm all terraces) found on the continental
margin hard bottoms of both North and South Carolina; hard bottom can also be other natural
outcroppings of limestone or unnatural man -made debris/structure.
All hard bottom vertical structure attracts and supports a diverse assemblage of invertebrate colonizers (eg
– sponges, seaweed) which in turn attract and support a diverse assemblage of vertebrate organisms. All
nearshore hardbottom is designated EFH for snapper, grouper, gag grouper, mackerel, and spadefish. The
NCDMF website states that hard bottom provides nursery habitat for grouper, spadefish, and black sea bass
while king mackerel, gag grouper, and grouper forage above or on hard bottom itself
(http://portal.ncdenr.org/web/mf/habitat/hard -bottom). The NCDMF website also states this EFH provides
spawning area for black sea bass, grouper, and damselfish and refuge for gag grouper and black sea bass.
The submerged remnants of the three groins , which are south of Buxton and the Avon Pier, provide similar
functions for surf zone fish as that provided by hard bottom EFH of deeper water (e.g., diversity of surfaces
for colonization, complexity of refugia, alternative food/prey sources). As m entioned elsewhere turbidity
of the surf zone is often high due to natu ral conditions. Visually oriented capture of prey may be
temporarily disrupted for some fish, but turbidity also provides increased cover for others. Any turbidity

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that does occur is likely to be of shorter duration than that associated with some weather e vents but
nonetheless could affect some of the filter -feeder colonizers which provide refuge or are prey to managed
fish of the surf zone . Considering that there is limited hard bottom habitat in the proposed project area,
and the only hard structures are pilings of Avon Pier in the active surf zone, adverse effects are not
expected to be long -lasting or cause significant impact to hard bottom EFH or the life stages of
managed species which may be in the vicinity .
Unconsolidated/shallow Subtidal Bottom – this EFH consists of soft estuarine or marine sediments
inhabited by a diverse assemblage of invertebrates that serve as prey to demersal fishes. Some managed
species that require this essential habitat include, bluefish, red drum, snapper grouper, spiny l obster,
summer flounder, smooth dogfish, and numerous shark species. Typically, very mobile in response to
wave and current conditions, these sediments lack stable surfaces for extensive vegetation or animal
attachment. Changes in type or amount of sedime nt supply, energy of wave and currents, and changes in
water quality chemistry drive the biodiversity within this EFH.
In the project vicinity, this EFH is found beneath both estuarine and marine waters, but for the same
reasons given for other estuarine EFHs above, only the marine sediments of this EFH will be evaluated
further. The offshore component of this EFH is typically more taxa rich than the surf zone and nearshore
components because of differences in sediment transport forces and the dynamics o f breaking waves in
the surf zone. Subtidal soft bottom may contain up to 600 benthic species, and the intertidal zone of the
lower beach is diverse with meiofauna, but the beach benthic community is primarily composed of 20 to
50 species of macrofauna (D eaton et al 2010 and NCDEQ 2016a,b). Marine EFH of this type is found both
within the project vicinity (within 2 miles of project area) and within the project area itself (offshore borrow
area and Avon beach intertidal beach/surf zone).
Dredging of sedi ments in the borrow area will disturb and dislodge benthic organisms and either cause
mortality from burial or entrainment, or disrupt their normal behaviors during the disturbance window.
Benthic dependent fish in the area, and/or their predators, along w ith various life stages of other managed
species may also experience entrainment mortality (eggs and larvae are particularly likely to suffer lethal
effects due to dredge processes) or avoidance behavior effects due to noise or turbidity, or physiological
effects such as clogged gills and visual impairment. In ASMFC’s Habitat Management Series #14, beach
nourishment and dredging were rated as medium threats for benthos -dependent species such as red drum
(due to changes in prey community, preferred substrat e changes and burial of individuals) while climate
change and coastal development were rated as high threats (Odell et al 2017).
Beach disposal of the dredged sediments can affect fishery resources through burial of intertidal and surf
zone resources that managed fish may utilize. However, some demersal fish species are sometimes
attracted to this type of disturbance (northern kingfish) and feed on the numerous fauna that may be
suspended in the water column from the dredging or disposal activity. Other more sensitive demersal
species can opt to move away to adjacent feeding areas (bluefish) (USACE 2001). While Deaton et al (2010,
page 364) acknowledge “the relative quick recovery on intertidal and shallow subtidal benthic
communities” assoc iated with soft stabilization projects on oceanfront shorelines such as bulldozing,

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without adequate best management practices known to enhance biological recovery, recovery rates in
mined areas are usually longer. Periodic storms affect benthic communiti es along the Atlantic coast to a
depth of about 115 ft (35 m); therefore, the soft bottom marine benthic community tends to be dominated
by opportunistic taxa that are adapted to recover relatively quickly from disturbance (Posey and Alphin
2001; Posey and Alphin 2002 in Deaton et al 2010; and NCDEQ 2016).
Managed species are attracted to this EFH largely due to its use by their preferred food, a process driven
by the dynamics of a typical food web which is built from the bottom to the top and largely de pendent on
the benthic community in the unconsolidated sediments. Spatial and temporal variation in the benthic
community prey species can therefore affect growth, survival, population levels of predators and all higher
trophic level species (Normandeau A ssociates 2014). The annual and seasonal variability in the benthic
community of this EFH is well documented and when subject to storms (hurricanes or nor’easters common
to the Outer Banks) project effects can be difficult to distinguish from natural proc esses (Deaton et al 2010,
NCDEQ 2016a,b). However, known factors which maximize benthic biological recovery rates in the
offshore portion of this EFH include use of hopper dredges, shallow excavation, use of topographic highs,
and rate of sand movement. In US Gulf and Atlantic sandy borrow areas studied within BOEM jurisdiction,
general faunal recovery (total abundance and biomass) has been shown to vary from 3 months to 2.5 years;
however, paucity of long term studies suggest that diversity and dominants composition may take 3.5
years (Michel et al 2013). Those factors which maximize recovery in the beach intertidal zone include the
following:
 grain size (similarity between native beach and borrow source is considered the most
important factor; this comp atibility is the main component of the sediment criteria
requirements in North Carolina in place since 2007),
 season of nourishment (winter placement avoids peak recruitment periods),
 frequency of nourishment (allow for growth to maturity across years),
 location of sediment placement (maintain stable geomorphology across the normal
beach seasonal profile to ensure sand remains in the system as long as possible), and
 rate of longshore transport (upstream recruitment opportunity).
No infilling fines in t he borrow area and accurate placement of properly sized sediment at Nags Head
Beach in 2011 allowed a full suite of species similar to the native beach and offshore zone to recolonize
the impact areas within one season and by the second year taxa richness and abundances were similar to
controls (CZR-CSE 2014).
In high energy beach and shoal borrow area environments frequently disturbed by natural events, infauna
are well adapted to natural perturbations by being small bodied, short lived, with a maximum r ate of
fecundity, efficient dispersal mechanisms, dense settlement, and rapid growth rates. Burial or temporary
exposure from dredging could also be beneficial or problematic depending on species and niche (a more

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mobile fauna may be able to dig verticall y to the new surface and avoid burial and less mobile prey species
temporarily exposed may provide more available food source for predator species).
Dredging in the borrow area and sand placement on the beach may temporarily disrupt food webs, change
predator-prey relationships, reduce community stability, and change age structure of populations by
selective mortality. However, it is recognized that tube dwellers and permanent burrow dwellers are most
susceptible to these types of disturbances compared to more mobile organisms.
A study of 50 dredge and disposal projects concluded that benthic recovery measured in months was
associated with shallow, naturally disturbed habitats, unconsolidated fine grain sediments, and univariate
analytical approaches while longer recovery (years) was associated with deep stable habitats, sand and
gravel sediments, and multivariate or functional group analytical techniques (Wilber and Clarke 2007).
This same study also noted that absence of both deposit feeders and of mi d-depth burrowers may indicate
an area is in a state of recovery. Polychaete worms and crustaceans recover most quickly (several months)
while deep burrowing mollusks are slower and may take several years (Rutecki et al 2014 and Brooks et al
2006, respectively). Studies have also shown that avoidance of the peak larval recruitment period (early
spring in the eastern US) can have a beneficial effect on the recovery rate (Wilber et al 2009). The Avon
nourishment is proposed to occur in the summer. Finally , the scale of the Action Area will be a small
fraction of the available unconsolidated marine shallow subtidal bottom and natural recruitment of
benthic species is expected to be rapid from surrounding undisturbed areas.
While some disturbance, mortality, and burial will occur with dredging and sand placement
activities, these effects are not expected to be long -lasting or cause significant impact to this EFH or
the life stages of managed species which are found within this habitat.
Cape Hatteras Shoals – these shoals are part of the sandy shoals of capes and offshore bars EFH for
Coastal Migratory pelagics, Highly Migratory Species, and summer flounder, a habitat of concern for red
drum, and HAPC for sandbar shark. Such shoals include the marine soft bot tom community identified and
discussed in the CHPP (Deaton et al 2010 and NCDEQ 2016 ). Diamond Shoals at Cape Hatteras are a major
sink in the coastal sediment transport system and are formed by convergent waves and longshore currents
associated with cuspate forelands (Moslow and Heron 1994). The shoals are fed by sand moving south
along the north segment of Hatteras Island under predominant northeast winds and waves, and sand
moving east along the southern arm of Hatteras Island under prevailing south west winds and waves; as
such the individual features (ridges and troughs) shift in response. Diamond Shoals encompass over
15,000 acres of shoal habitat (an area approximately 7 by 2.5 nautical miles extending southeast from Cape
Point beginning ~12,000 ft south of the project area. A continuous supply of sand from adjacent beaches
feeds Diamond Shoals and maintains them as an underwater extension of the coastlin e (Armstrong et al
2013). Diamond Shoals contains roughly 100 times the volume of sediment i n the proposed borrow area
within the upper ~ 8 ft of substrate.
Cape Hatteras also marks a convergence zone where the southerly flow of the Labrador Current meets the
northerly flow of the Florida Current/Gulf Stream and where the Florida Current separat es from the

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USACE–Wilmington District (NC) 179 Avon Village, Dare County (NC)
continental shelf and the flow becomes the singular Gulf Stream, and where the current begins its passage
over the deep ocean. This dynamic zone of mixed oceanic waters marks a distinct transition between
warmer Gulf Stream waters and cooler L abrador waters with associated upwelling of nutrient laden waters
and changes in dominant species. Cape Hatteras shoals represent the northern and the southern terminus
of the range of numerous species and results in a diverse biological assemblage. These two currents deliver
both warmer species from the south and cooler species from the north to the shoals in the area and
adjacent habitats.
The Cape Hatteras shoals support seasonal congregations of baitfish and shrimp preyed upon by
numerous managed spec ies (eg – red drum and Spanish mackerel) and serve as staging areas for other
coastal migratory species. The named shoals further north of Cape Hatteras (eg – Kinnakeet and Wimble)
serve as spawning habitat for summer flounder aggregation s (MAFMC 1998, De aton et al 2010, NCDEQ
2016). Nearshore ocean waters and subtidal bottom habitat also serve as important pupping areas for
several species of small coastal sharks (eg – Atlantic sharpnose, bonnethead, blacknose shark); larger
coastal sharks pup in these areas to a lesser extent.
Acoustical arrays deployed south of Cape Hatteras (2008 -2011 and 2012 -2014) demonstrated how the
shoals act to constrict both shelf habitat and the migratory corridors of several highly migratory and/or
managed species whose a coustic tags were tracked (eg – spiny dogfish, Atlantic sturgeon, and sandbar
shark) into this narrow convergence zon e (Rulifson et al 2020). Some tagged Atlantic sturgeon remained
in the area all year and other Atlantic sturgeon and some shark species rem ained in the area only during
the winter (November to April was shown as most critical period for these wintering speci es) ( et al 2020).
While not considered to be within the nearby Kinnakeet Shoals found north of the project area, the smaller
shoal targeted within the proposed borrow area likely formed under similar dynamics and performs
similar functions.
The water depth in the shallowest portion of the propose borrow area ranges from about 30 to 35 ft (9 to
11 meters) at the top of the ridge to about 4 0 to 45 ft (12 to 14 meters) in the flatter topography on either
side of the gentle slopes of the ridg e. As described in the EFH assessment for the 2014 nearby Rodanthe
beach nourishment project, modeling performed for that project showed that for shoals in water depths
like the Avon borrow area, waves more likely influence their formation rather than currents (USACE 2013).
However, the borrow area depths are at the shallower end of the 10 to 30 m range of the model range.
Another model suggests that pos t-dredge infill of borrow areas is largely dependent on whether or not the
ridge is active, whether or not there is sand available for refilling, and the actual dredging location within
the ridge (CSA International et al 2010). This model suggests that th e best location for dredging on a shoal
or ridge, at least from a physical standpoint, is the leading, down -drift edge as the borrow scour area can
then be fed by ongoing physical (wave) processes which if active, are presumed to quickly refill the
borrowed area. The ridge crest would be the second best, followed by the trailing edge. If the ridge is not
active, only larger scale processes, e.g., major storms will rebuild the ridge. The Dibajnia and Nairn (2011)
model referred to in the Rodanthe EFH asses sment also tested various dredging methodologies and
subsequent reformation scenarios in order to suggest ways to dredge offshore that would protect and

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maintain the morphologic integrity of ridge and shoal features; thereby also affording protection of or
reestablishment of benthos and fish habitat. In the present case, only a small part of the isolated shoal
will be dredged, leaving shoal topography in the vicinity of the Action Area.
Only coarse grain sediment (≥90 percent sand) will be placed on the ocean beach strand in Avon and any
turbidity with this placement is not expected to extend to the Kinnakeet or Cape Hatteras sandy shoals.
However, turbidity associated with the removal o f sediment from the offshore borrow area (in an unnamed
shoal adjacent to the larger shoal) will have short term impacts on the water column in the immediate
vicinity and potentially allow some settlement of fines to the bottom. However, the associated tur bidity
effects from dredging in the borrow area and from sand placement on the Avon beach will not adversely
impact nearby shoals with altered longshore currents or altered tidal climate. For additional information
on this EFH, see Appendix F.
Use of the topographic high within the proposed borrow area, the overall shallow excavation depth of the
hopper dredge, and the borrow site’s location in an area of high sand movement are important factors
that will maximize biological recovery rates (Deaton et al 2010; NCDEQ 2016 ). Further, the area of the
proposed borrow excavations represents less than 1 percent of the extant similar habitat available nearby
in Diamond Shoals and Kinnakeet or Wimble Shoals. Therefore, the project is not expected to pose a
threat to Cape Hatteras Shoals EFH or the life stages of managed species which are found within this
habitat; any impacts that may occur are within reasonable limits .

6.5 Potential Impacts on Special Aquatic Sites (Subpart E)
Potential Impacts on Special Aqu atic Sites
Special Aquatic Sites N/A No Effect Negligible
Effect
Minor Effect
(Short-Term)
Minor Effect
(Long-Term)
Sanctuaries and R efuges X
Wetlands X
Mud flats X
Vegetated Shallows X
Coral reefs X
Riffle Pool Complexes X
No discussion is needed. All not applicable (N/A) based on USACE definition of special aquatic sites.

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6.6 Potential Impacts on Human -Use Characteristics (Subpart F)
Potential Impacts on Human-Use Characteristics
Human Use Characteristics N/A No
Effect
Negligible
Effect
Minor Effect
(Short-Term)
Minor Effect
(Long-Term)
Major
Effect
Municipal and Private Water Supplies X
Recreational and Commercial Fisheries X X
Water-Related Recreation X
Aesthetics X
Parks, National and Hi storical Monuments,
National Seashores, Wilderness Areas,
Research Sites, and Similar Preserves
X

Recreational and Commercial Fisheries are rated a negligible or short-term minor effect because t he
“Preferred Alternative–Beach Nourishment with Summer Construction” will disturb a portion of the ocean
bottom at the borrow areas and displace in situ organisms on which certain recreational and commercial
fisheries feed during nourishment operations. Impacts to the benthic communities are expected to be
neutral and short-term based on detailed monitoring results after another nourishment project at Nags
Head in Dare County (CSE–CZR 2014). Some impacts will be positive in connection with sediment
excavation and releases of organisms into the water column where they will be more readily available to
fish (cf – USACE 2001). Impacts near active dredging and fill placement will be negative, but short -lived,
for fish that tend to avoid turbid water. The population of benthic organisms will be imp acted, but not
likely perma nently impacted with the recovery of populations over time periods related to the growth
cycles of individual organisms.
Water-Related Recreation is rated a major positive effect because the “Preferred Alternative –Beach
Nourishment with Summer Construction” will widen the recreational beach and provide more area to
accommodate visitors on whom the applicant depends for the economic well -being of the community.
The “No-Action Alternative” would have a negative effect on water -related recreation because beach area
would decline over time as erosion continues.
Aesthetics is rated a major positive effect because the “Preferred Alternative–Beach Nourishment with Sum-
mer Construction” adds sand to the beach system, provides a protect ive buffer between the ocean and the
foredunes, and reduces the need for emergency shore protective devices such as sand bags. The project
design seeks to construct a profile closely resembling the natural beach using sediments that have similar
texture. The project will be left to adjust naturally to tides, waves, and winds so that over time the
renourished beach takes on characteristics of a nat ural beach/dune system. The “No-Action Alternative”
would degrade aesthetics because continued erosion would encroach on the foredune and developed
property, leading to the installation of emergency protection such as sand bags. Buildings along portions
of the project area would become exposed on the active beach, thus detracting from the aesthetic quali ty
of the oceanfront.

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Parks, National and Historical Monuments, National Seashores, Wilderness Areas, Research Sites, and
Similar Preserves are rated a major positive effect because the nourishment project at Avon will add sand
directly to approximately 2 .5 miles of developed National Seashore beach, and benefit the undeveloped
beach to the south between Avon and Buxton. This southerly transport and deposition was demonstrated
after the initial nourishment project at Buxton. Sand will move from the proposed project area to the
undeveloped National Seashore beach under both alternatives. However, the “Preferred Alternative–Beach
Nourishment with Summer Construction” adds a significantly larger new sand supply to Outer Banks beaches
than would be possible with wi nter construction. This sand would be available to augment the existing
sand supply, thereby lessening the effect of cannibalization of the existing beach during erosion events.
6.7 Pre-Testing Evaluation (Subpart G)
The following information has been considered in evaluating the biological availability of possible contami-
nants in dredged or fill material. There is no known contamination in the proposed borrow area sediments,
which consist of ~99 percent sand or granular sized material [mostly quart z and calcium carbonates
(shell)]. Because the borrow site is open ocean bottom substrate away from any freshwater river
discharges, the likelihood of contaminated sediments is negligible .
Possible Contaminants in Dredged/Fill Material
Physical characteristics NONE
Hydrography in relation to known or anticipated sources of contaminants NONE
Results from previous testing of the material or similar material in the vicinity of the project NONE
Known, significant sources of persistent pesticides from land runoff or percolation NONE
Spill records for petroleum products or designated (Section 331 of CWA) hazardous substances NONE
Other public records or significant introduction of contaminants from industries, municipalities, or other sources NONE
Known existence of substantial material deposits of substances that could be released in harmful quantities to
the aquatic environment by man-induced discharge activities NONE
6.8 Evaluation and Testing (Subpart G)
Not applicable.
6.9 Actions to Minimize Adverse Impacts
Actions to Ensure Adverse Effects are Minimized
Yes No
Actions concerning the location of the discharge X
Actions concerning the material to be discharged X
Actions controlling the material after discharge X
Actions affecting the method of dispersion X
Actions affecting plant and animal populations X
Actions affecting human use X

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The “Preferred Alternative –Beach Nourishment with Summer Construction” incorporates contr ols on the
areas where sediments will be dredged and on th e configuration of material as discharged along the active
beach. The location of the discharge will be along the wet -sand beach, working parallel to shore with
training dikes (if necessary) to retain material close to the shoreline and minimize turbidity . If poor quality
material (eg – high concentrations of fine-grained material) are encountered, the dredge will be moved to
other parts of the permitted borrow area until suitable sediments are found. The applicant and dredging
contractor have a mutual self-interest in placing beach -quality material rather than fine -grained silts and
clays that tend to wash offshor e and not expand the beach or count as pay volume.
After discharge, the nourished beach will be graded to slopes and elevations closely matchin g the native
beach. It will be measured to ensure the fill densities at each section closely match the design volumes
prescribed for the area. The discharge point will include spreaders at the end of the pipe to disperse
sediment across the profile and n ot leave depressions or points where significan t fine material can
accumulate. The fill will be placed seaward of all existing vegetation on the foredune or beach system. Fill
will progress gradually along shore , providing time for some species to move s eaward away from the
nourishment. As soon as a section is completed each day, it will attract pioneering species which will
eventually fill any vacant biological niches. These species (eg – polychaete worms and amphipods) will then
attract higher order species to the nourished beach until similar assemblages of species inhabit the area.
The project will disrupt human use of the beach in the immediate vicinity of the discharge point(s). As the
project progresses, newly nourished area will be open to the public within 24‒48 hours after the section is
complete. Thus, the time of impact to any given area of the project site will be limited to several days.
Similar to other nourishment projects, the applicant expects short -term, temporary, small-scale impacts
to human use in each section of the project.
6.10 Factual Determinations (Subpart B)
Factual Determinations of Potential Impacts
Site N/A No
Effect
Negligible
Effect
Minor Effect
(Short-
Term)
Minor Effect
(Long-Term)
Major
Effect
Physical substrate X
Water Circulation, Fluctuation , and Salinity X
Suspended particulates/turbidity X
Contaminants X
Aquatic Ecosystem and O rganisms X
Proposed Disposal Site X
Cumulative Effects on the Aquatic Ecosystem X
Secondary Effects on the Aquatic Ecosystem X

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The “Preferred Alternative–Beach Nourishment with Summer Construction” will seek, by design, to leave
similar substrates at the borrow site by excavating relatively shallow cuts that leave similar types and
textures of sandy material on the bed. Undisturbed nearby sediments of similar quality are expected to
slough or to be transported into dredged depressions, leaving similar quality material on the bottom for
recolonization by a similar suite of organisms. The proposed borrow areas contain sediments that closely
match the existing sub aerial beach. The impacts to physical substrate are therefore expected to be minor
and short-term. Nourishment sediments will mix with existing beach sediments over time , producing
indistinguishable differences.
Suspended particulates and turbidity are expected to produce minor, short -term impacts, but return to
ambient conditions upon cessation of pumping. As discussed in Sections 5.1 and 5.2, the bor row
sediments are relativel y coarse-grained and will have settling velocities measured in seconds to min utes.
Impacts to benthic organisms are expected to be minor and short -term as discussed in Section 6.4 .
Benthic populations are expected to fluctuate seasonally at similar rate s as unnourished areas based on
results of biological monitoring following another nourishment project at Nags Head in Dare County (CZR-
CSE 2014).
6.11 Findings of Compliance/Non -Compliance
Compliance with Restrictions on D ischarge
Site Yes No
• Is ther e a practicable alternative to the proposed discharge that would be less damaging to the environment (any
alternative with less aquatic resource effects, or an alternative with more aquatic resource effects that avoids other
significant adverse environment al consequences?)
N
• Will the discharge cause or contribute to violations of any applicable water quality standards? N
• Will the discharge violate any toxic effluent standards (under Section 307 of the Act)? N
• Will the discharge jeopardize the continued existence of endangered or threatened species or their critical habitat? N
• Will the discharge violate standards set by the Department of Commerce to protect marine sanctuaries? N
• Will the discharge cause or contribute to significant degradation of waters of the U.S.? N
• Have all appropriate and practicable steps (Subpart H, 40 CFR230.70) been taken to minimize the potential adverse
impacts of the discharge on the aquatic ecosystem? Y
The proposed Avon nourishment project will be constructed in th e most efficient and practical way
possible under present technology . There are no other practical alternatives for a project of the proposed
scale (~1.0 million cubic yards) to be accomplished in several months. The construction method offers
proven tec hnology that has been widely applied throughout the world. The method is principally
hydraulic and does not require chemicals, harmful additives, or special techniques to facilitate construc -
tion. Post-project maintenance relies heavily on natural wave p rocesses to shape the fill to the slopes and
morphol ogy typical of a natural beach. The proposed project construction would draw sediment from pre -
tested borrow sites and would cause some turbidity and some disturbance of bottom substrate , which is
unavoidable and will be performed in a way that minimizes long-term adverse impacts.

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7.0 GENERAL PUBLIC INTEREST REVIEW (33 CFR 320.4 and RGL 84-09)
7.1 Public Interest Factors
Numerous public interest factors were considered in connection with the propo sed nourishment project.
Table 7.1 provides a synopsis of fourteen (14) factors. Additional factors are discussed in more detail after
Table 7.1.
TABLE 7.1 Summary of Public Interest Factors and Likely Effects of Proposed Project Effects
None Detrimental Neutral*(mitigated) Negligible Beneficial Not Applicable 1. Conservation: Neutral and Beneficial Effects (LT)
Conservation of native species will benefit from the proposed project as the widened beach and rebuilt
dunes will improve or add habitat. Avon beach and its environs is a permanent and temporary home to a
variety of terrestrial and aquatic life, including threatened, endangered, and other protected species. These
species depend on the special habitats resulting from the transition between th e northern and southern
habitat zones and the dynamic nature of the barrier islands.
The project extends along 2.5 miles of developed Cape Hatteras National Seashore beach, designated a
Globally Important Bird Area (GIBA), which serves as major resting and feeding grounds for migratory birds
throughout the year. Shorebirds are most abundant from late spring through the summer months.
Mitigation procedures would be implemented for the piping plover (T), rufa red knot (T), roseate tern (E),
and loggerhead sea turtles as described elsewhere in this EA.
X X
2. Economics: Beneficial Effects
The restoration of Avon beach is essential to the economy of Dare County and protection of NC 12, the only
access road servicing communities on Hatteras Island. A breach or flooding of the road at Avon effectively
shuts down much of the Hatteras Island economy until floods subside or repairs can be made. Tourism is
the largest industry in Dare County, which contributes to a significant portion of County assets and
revenues. The NCDOC estimated that tourism in Dare County produced an annual economic impact of $1.02
billion in 2014. The economy generates economic activity through home rentals, hotel visitation, food and
beverage services, recreational fishing and water-sports charters, commercial fishing, fishing tournaments,
and associated support services.
Dare County collects a 5 percent Occupancy Tax on gross receipts derived from accommoda tions rentals,
along with tax collected on restaurant food/beverages. In addition, real-estate taxes generate considerable
revenue for the County, which is used toward emergency services, fire, and police protection.
X
3. Aesthetics: Beneficial Effects
The aesthetics (how well a beach looks) are not only essential to attracting tourists and homebuyers, but to
indicating how well a beach and its environs can support wildlife. The 2018 Buxton nourishment project
added beach along ~3 miles of vulnerable dunes protecting Highway NC 12. This reduced the threat of a
breach and closure of the highway and helped prevent damages to oceanfront properties in Buxton. A
similar project as proposed for Avon would provide many benefits, including wider dry sand beach
enhanced critical habitat for sea turtles, piping plover, red knots, and other threatened species.
Nourishment along Avon would restore and help maintain a soft edge of dunes and vegetation between
structures and the ocean—a view that is typically associated with a healthy natural beach system. It would
also feed sand downcoast to undeveloped sections of the Seashore.
X

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4. General Environmental Concerns: Beneficial Effects
It is widely recognized that the beaches of Dare County are a valuable ecological re source. Of nearly 89 miles
of barrier island shoreline locat ed in Dare County, only half is developed. The remainder, made up of south
Bodie Island and the majority of Hatteras Island to Hatteras Inlet, will remain undeveloped in perpetuity as
part of Cape Hatteras National Seashore. This makes Avon, Buxton, and other Hatteras Island beach
communities even more important in providing public beach access. Highway NC 12 is the critical link for
Hatteras Island communities as well as National Seashore facilities. The damage associated with severe
storms results in road closures, loss of oceanfront dunes, damage to maritime forests, and loss of habitat
and wildlife use. Whether addressing normal or severe impacts, measures to maintain a healthy beach
environment are essential to maintenance of access, a positive experience for the beach visitor, and for
resource conservation.
X
5. Fish and Wildlife Values: Neutral (Mitigated) and Beneficial Effects
Avon beach and its environs is a permanent and temporary home to a great variety of terrestrial and aquatic
life, including threatened, endangered, and other protected species. Therefore, fish and wildlife values are
very high and are a main reason the area is frequently visited. Appendix E‒Biological Assessment evaluated
29 species that had the potential to occur in or near the project area and were listed by the USFWS or NMFS
to receive protection under the 1973 ESA (as amended). These 29 species included two plants, twelve birds,
five fish, six reptiles, and four mammals.
In addition, animal species designated by the NCDEQ Wildlife Resources Commission (NCWRC) and the
NCDEQ Natural Heritage Program (NCNHP) as threatened, endangered, or species of concern receive legal
protection by the ESA (Article 25, Chapter 113, NC General Statutes 1987). Plant species determined by the
Plant Conservation Program (NC Department of Agriculture) and the NC Natural Heritage Program as
threatened, endangered, or special concern are protected by the NC Plant Protection and Conservation Act
of 1979.
Regarding fish species, the applicant has notified NOAA’s Southeast Regional Office (SERO) of the
proposed project. It will continue to coordinate with the several agencies assigned to protect Essential Fish
Habitat (EFH) and Habitat Areas of Particular Concern (HAPC) to receive the required concurrence on the
effects of analysis of EFH and the conservation/mitigation recommendations included in Appendix
F─Essential Fish Habitat Assessment.
X X
6. Flood Hazards: Beneficial Effects
A healthy beach profile with rebuilt dunes accomplished by the proposed project will reduce risks from
storm runup over the dunes underneath beach home properties. Hurricane flooding often occurs with a
sand-impoverished beach and low dunes. A 2011 nourishment project in Nags Head was tested during and
immediately after its construction by hurricanes Irene and Sandy. A flat, wide beach remained after the
storm with the majority of nourishment sand retained in the littoral zone. When beaches are augmented by
new sand from an external source and maintained through a re gular nourishment program, storm impacts
of under-house and street flooding are significantly reduced or avoided.
X
7. Floodplain Values: Beneficial Effects
All federal agencies are required by Executive Order 11988 (Floodplain Management) to evalua te the likely
impacts of their actions in floodplains. The objectives of the EO 11988 are to avoid as much as possible, the
short- and long-term adverse impacts associated with occupancy, modification, or destruction of
floodplains and to avoid indirect support of development and new construction in such areas where there
is a practicable alternative.
The barrier-island floodplains help to reduce the impact of hurricanes and other storms on the shorelines
that they shelter. These floodplains provide storm-water holding capacity, reducing runoff that could
otherwise flood developed areas. Storm events such as hurricanes and nor’easters (winter storms along the
mid-Atlantic coast) and associated wave action and high precipitation are the main sources of flooding.
North Carolina’s barrier islands have historically been and continue to be affected by coastal forces and
flooding events. The barrier islands of the Outer Banks are predominantly flat and narrow and lie adjacent
to the shallow and wide Pamlico Sound. The proposed project area itself lies completely within the 100-
year floodplain (https://fris.nc.gov/fris/index.aspx?FIPS=055&ST=NC&user=GeneralPublic , accessed May
2015).
Generally, lands along the ocean beaches and adjacent to the sound (at wide points) are in flood zone
VE, which is the flood insurance rate zone that corresponds to 100 -year coastal floodplains that have
X

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additional hazards associated with storm waves, high water tables, and periodic flooding. Zone VE is also
referred to as the Coastal High Hazard Area. Only zone VE is found within the proposed project area.
None of the alternatives presented by the applicant would elevate the project area above the floodplain
or reduce the capacity and function of the affected floodplain. The propose d project can only occur within
the floodplain, but it would not reduce the amount of floodplain. It would likely widen the recreational
beach and potentially increase the capacity and function of the shoreface floodplain. The proposed project
would not pose a risk to humans, a risk to investment, or impact floodplain processes and values. The
proposed project in fact would create the opposite effect: reduce risk to humans and investment, and
decrease the effects of floodplain processes on property adjoini ng the shoreline. Therefore, the project is
deemed exempt from the need to prepare a floodplain statement of findings, and the impact of floodplains
is dismissed from further analysis.
8. Land Use: Beneficial Effects
By improving the beach, the proposed project would add value to land use in the immediate and general
area. No conflicts are identified between the proposed project and land use plans, policies, or controls for
the project area. The design of the built environment would remain consta nt within the project area with
the oceanfront bordered by the present beach community. Existing coastal zone management (CZM) rules
prohibit any new development on restored beaches. In accordance with North Carolina CZM rules
(deq.nc.gov/about/divisions/coastal-management/coastal-management-rules, accessed May 2021), a
mean high water survey would be performed along the proposed project area to record its location prior to
placement of any sand.
Rodanthe, Avon, Buxton, and other villages on Hatteras I sland support a thriving tourism business and
road system, providing outstanding access to National Seashore beaches and remote areas of the Outer
Banks. Millions of visitors travel to Outer Banks beaches each year, and a majority use NC 12 to access the
National Seashore and Hatteras Island communities. Tourism in coastal counties like Dare County
maintains infrastructure, housing, and beaches to support the demand for access to the shore.
X
9. Navigation: Negligible Effects
The proposed project would be constructed on the beach and would not be conducted near or in a port,
waterway, or other access point for ships and boats. If any actions are approved and permitted which
involve dredging in navigable waters of the United States, the applicant or contractor will be required to
contact the US Coast Guard so that a Notice to Mariners is published prior to mobilization of equipment or
any operations. The Notice would identify the equipment and potential obstructions that may be in the
project area and the dates of the action. Due to the visibility of the cutterhead and hopper dredges offshore,
vessels would be able to avoid entering the worksite over the borrow area. The buffer zones established to
protect cultural resources would also alert passing yachts, sailboats, sportfishing, and recreational boats. X 10. Shoreline Erosion and Accretion: Beneficial Effects
The purpose of the proposed project is to replace sand lost to natural causes on the beach and to restore
damage done by hurricanes Florence and Dorian. Therefore, the project would be designed to offset
shoreline erosion, especially the ~1 mile of severe erosion south of Avon Pier. It would also be designed to
rebuild dunes and restore a healthy beachface profile. The volume of sand need ed to restore the beach
profile would be calculated by the applicant’s project engineers to ensure the dredged sand is apportioned
along the entire length of the 2.5-mile shoreline according to need. Accretion would be artificially created
by the pumping of up to ~1.0 million cubic yards of sand onshore, which will be moved and shaped by land-
based equipment. The nourishment design includes long transitions at the end to improve project longevity
and benefit as much of the shoreline as practicable under th e fiscal requirements of the applicant.
X
11. Recreation: Beneficial Effects
A restored beach at Avon will improve the recreational outlets it provides. The additional volume of sand on
the beach will make activities such as beachcombing, sunbathing , day camping, and swimming a more
enjoyable experience with added area to accommodate more visitors.

X
12. Water Quality: Negligible Effects
The proposed project would cause negligible effects on water quality. Coastal waters offshore of Avon are
classified as “SB” waters by the State of North Carolina (NCDEM 1989), meaning they can be used safely for
X

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swimming, primary and secondary recreation, fish and wildlife propagation, and all other uses requiring
lower quality waters (NCDEM 1991) (USACE 2010). To maintain the SB designation, waters affected by the
proposed project must be analyzed to ensure the water stays within the SB-designated range.
Water quality at Avon beach is affected by the frequent, high-wave energy off the beach, which tends to
inhibit the accumulation of silts and clays. The inshore zone has free circulation of oceanic waters with little
direct input of fine-grained material from nearby inlets or estuaries. While dredging operations will mobilize
sediments in the borrow area, low percentages of silts and clays are expected to limit the scale of dredge -
generated sediment plumes in the water column. Sand - and granular-sized material settles almost
instantaneously relative to the settling rates of silts and clays.
Diver observations and borings by the applicant over the proposed borrow area showed low
concentrations of suspended sediment or in-situ silts and clays. Low concentrations of fine-grained material
tend to minimize the potential for pollutants to adsorb on particles and become concentrated within the
proposed project area. Therefore, water quality will return rapidly to its pre -project status and is expected
to retain its SB classification throughout project operations.
13. Consideration of Property Ownership: Beneficial Effects
The value of oceanfront and ocean view property will increase and be maintained as a result of the proposed
project. Property owners will benefit financially, aesthetically, and recreationally from nourishment. Nearly
33 percent of Dare County’s tax levy funds Dare County schools. Beach community properties such as Avon’s
effectively subsidize the Dare County school system via property taxes on high -value real estate.
Any reduction of the effective subsidy derived from Avon property and economic activity would result in
increased property taxes over the remainder of the County. Loss of the first row s of oceanfront properties
would result in an incremental county-wide tax increase to make up for the reduced tax base.
X
14. Needs and Welfare of the People: Beneficial Effects
Benefits to the people have been described above in economic, land use, and recreational terms. Another
factor is the strengthening of the social fabric when friends and families vacation together. Generations of
families living inland have been drawn to Avon and the northern Outer Banks for rest and relaxation. They
faithfully keep their annual tradition of hosting family gatherings (in owned or rented properties) at the
beach. This social tradition extends well beyond the County and draws visitors from many states and foreign
countries. As a popular destination, Avon and Cape Hatteras’ many assets build community and civic
welfare in a wholesome vacation setting.
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7.2. Other Public Interest Factor s
7.2.1 Geologic and Mineral Resources
The National Park System encompasses lands with significant geologic features, landforms , and
landscape characteristic of the United States. The principal landform associated with Cape Hatteras
National Seashore is the barrier island and its associated beaches, capes, inlets, sounds , and related
habitats. The Proposed Action Area does not represent any unique barrier island features that are only
found within the ~2.5-mile-long Avon segment of the Outer Banks. Furthe r, the Avon segment has been
modified by sand scraping, dune re -construction after storms, installed vegetation and emergency
shore protection devices, such as sand bags, to protect developed property. Any pr oposed action by
the Applicant should seek to ma intain or improve upon this altered landscape for the general benefit
of park users and indigenous wildlife.
No mineral resources, gas or oil reserves, or unique geologic features would be impacted by the
project. Therefore, the impact topic of geologic resources is dismissed from further analysis. The
impact of the project on the form and profile of the barrier island, beach, and borrow area is addressed
under Appendix D‒Littoral Processes.
7.2.2 Soils and Upland Topography
The proposed project would involve the placement of beach quality sand in the active beach zone. It
would not involve any direct sand placement on existing vegetation . The sand placement would seek to
match the natural elevation and slope of the dry sand beach , while widening this zone without significant
change in topography. The proposed project would involve some dune re -building with the aim of
restoring a protective dune where it has been lost or degraded due to accelerated erosion . It would
increase sand volume and widen the beach . Because the proposed project would not alter the basic
topography of the project area or modify soils where vegetation exists, the issue of soils and upland
topography are dismissed from further analysis .
7.2.3 Wetlands
Executive Order (EO) 11990 – Protection of Wetlands, directs all federal agencies to avoid, to the
maximum extent possible, the long - and short-term adverse impacts associated with the destruction
or modification of wetlands and to avoid direct or indirect support of new construction in wetlands
wherever there is a practicable alternative. In the absence of such alternatives, parks must modify
actions to preserve and enhance wetland values and mini mize degradation. Consistent with EO 11990
and NPS Director’s Order #77 –1: Wetland Protection, the National Park Service adopted a goal of no net
loss of wetlands. Director’s Order #77 –1 states that for new actions where impacts to wetlands cannot
be avoided, proposals must include plans for compensatory mitigation that restores wetlands on NPS
lands, at a minimum acreage ratio of 1:1.

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For the purpose of implementing EO 11990 on NPS -managed lands, any area that is classified as a
wetland according to the U SFWS Classification of Wetlands and Deepwater Habitats of the United
States (Report FWS/OBS -79/31 – Cowardin et al 1979) is subject to NPS Director’s Order #77 –1 and
its implementation procedures. Under the Cowardin definition, a wetland must have one or m ore
of the following three attributes:
 At least periodically, the land supports predominantly hydrophytes (wetland vegetation)
 The substrate is predominantly undrained hydric soil
 The substrate is non -soil and is saturated with water or covered by shallow water at some time
during the growing season of each yea r
The Cowardin wetland definition encompasses more aquatic habitat types than the definition and delinea -
tion manual used by the USACE for identification of wetlands under Section 404 of the Clean Wa ter Act.
Federal regulations define wetlands as:
Those areas that are inundated or saturated by surface or ground water (hydrology) at a frequency
and duration sufficient to support, and that under normal circumstances do support, a prevalence of
vegetation (hydrophytes) typically adapted for life in saturated soil conditions (hydric soils).
Wetlands generally include swamps, marshes, bogs, and similar areas (40 CFR 232.2 (r).
Wetlands can be identified by the presence of those plants (hydrophytes) that are adapted to life in the
soils that form under flooded or saturated conditions (hydric soils). The proposed Avon project area is a
high-energy, active beach zone where mobile sandy sediments preclude the establishment of vegetation.
The 1987 USACE Wetlands Delineation Manual and its regional supplements require that all three of the
parameters listed above (hydrophytic vegetation, hydric soil, wetland hydrology) be present in order for
an area to be considered a wetland.
Under the Cowardin wetland defin ition, the intertidal beach is classified as a marine wetland. Marine
wetlands are found along the entire length of ocean shoreline between extreme high tide and extreme low
tide and are subject to high wind , current, and wave energy. The intertidal beac h zone (Cowardin marine
wetland) continually adjusts to wave energy and sand supply, maintaining a profile under conditions of
erosion or accretion. Prior to the 201 7–2018 beach nourishment project, the intertidal zone in the
proposed project area was degraded by the presence of sand bags and homes with foundations in the
active surf zone . Any activity that increases the sand supply within the project area is likely to maintain or
incrementally increase the area of marine wetlands, provided the introduced sediments are similar in size
and texture as the native beach. In preparation for the proposed nourishment project , sand coring was
conducted in a broad sand search area to select the best offshore sediment match for the beach of the
project area.
For the proposed project, t he following best-management practices would be observed:
 Nourished shoreline would have similar slopes as the existing shoreline.
 Use of heavy equipment to shape the pumped sand would leave no trace of disturbance when
restoration efforts are complete

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Because no statement of findings for wetlands needs to be prepared, the impact on wetlands is
dismissed from further analysis.
7.2.4 Energy Resources
There are no known fossil energy resources in the proposed project area. Waves and winds are considered
an energy resource with potential to augment local power supplies along the coast. The proposed project
would not alter wave or wind power and would only impact a small area of ocean bottom for a few months
during construction. Impacts on energy resources under the proposed project were considered, but
were dismissed from further analysis in this EA.
7.2.5 Visual Resources
The proposed project would create temporary, short -term impacts to the vistas characteristic of a
developed barrier island. Heavy equipment and a dredge pipeline would be placed on the beach and
would be visible to beachgoers in the vicinity of the active construction area. These impacts are
unavoidable and are associated with all earthmoving projects. However, upon project completion after a
few months of local impacts, all equipment would be removed and the project area would be left to evolve
naturally. The vistas after project completion are expected to remain the same as pre -project conditions
or to improve with removal of emergency sand bags along areas where they have been placed due to
severe erosion. Extra sand added to the beach system is expected to eventually build up along the back -
shore and toe of the foredunes. As the sand placed on the beach would closely match the native sand in
terms of color, texture, and grain size distribution, no long -term adverse impacts on vistas or user experi -
ence would occur . Visual resources of the project area were considered, but were dismissed from
further analysis in this EA.
7.2.6 Climate Change
Climate change refers to any significant changes in average climatic conditions (such as mean tempera -
ture, precipitation, or wind) or variability (such as seasonality, storm frequency, etc) lasting for an
extended period such as decades or longer. Recent reports by the US Climate Change Science Program,
the National Academy of Sciences, and the United Nations Intergovernmental Panel on Climate Change
(IPCC) provide evidence that climate change is occurring and may acce lerate in the coming decades.
Strong evidence exists to show that global climate change is being driven by human activities world wide,
primarily the burning of fossil fuels and tropical deforestation. These activities release carbon dioxide and
other heat-trapping gases, commonly called greenhouse gases, into the atmosphere (Climate Change
2007, www.IPCC.ch.2017).
Impacts of climate change on the project are likely to be of a subtle, gradual nature. A rise in sea level
would modify the beach profile and may cause wave attack to occur at higher elevations and/or be trans-
lated farther inland. Changes in climate such as general warming, changes in water availability, and storm
frequency, intensity, or duration could cause changes in the rate of sand loss o n the beach over decades.
While most people visiting or passing through would be unaware of the changes, changes in shoreline

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position may occur as a result of sea -level rise (SLR). Because SLR operates at long time scales and the
proposed project is des igned to last approximately five years , the impact of SLR over less than one decade
is expected to be small in relation to the scale and scope of the proposed proj ect.
Beaches are generally considered to respond rapidly to changes in sea level with profile s displaced upward
and landward in relation to the rate of SLR (Bruun 1962, NRC 1995). This process occurs episodic ally during
storm events whereby a new (higher) berm is formed in relation to the particular combination of high
waves, storm surge and tid es superimposed on the eustatic change in sea level. The amount of shoreline
recession associated with a particular SLR is a function of the average foreshore or beachface slope (NRC
1995, Dean 2002).
Best-available data and projections of future SLR indicate strong probability for a rise of 3 –6 centimeters
(cm) over the next ten years (IPCC 2017 —www.ipcc.ch). A rise of this magnitude would equate to shoreline
recession of ~0.5–1.0 m2 (1.5–3.0 ft) along the beach foreshore. Such a recession would be dwar fed by the
anticipated average widening (~60 ft) of the beach associated with the proposed project.
Two aspects of climate change must be considered in an envi ronmental impact analysis and are recom-
mended for consideration in an EA:
 Human impact on climat e change (ie – through our actions, the potential to increase or
decrease emissions of greenhouse gases tha t contribute to climate change)
 The impact of climate change on humans (ie – how are the resources that we manage likely to
change in response to cha nging climate conditions, and how does that change otherwise
affect our management actions and the impacts of those actions on the resource?)
The proposed project would not result in the construction of any permanent carbon -emitting infra-
structure. It wo uld also not result in any enhancement of vehicular use or create any new recreational
attraction that would increase vehicular carbon emissions. During the construction process, the proposed
project could result in a temporary increase in emissions of gr eenhouse gases from the operation of
construction equipment. However, because temporary construction impacts would cease on completion,
the proposed project would have no effect on climate change. The applicant considered the impact of
the proposed project on climate change, but dismissed it as an impact topic for further analysis.
7.2.7 Soundscapes
The National Park Service strives to maintain or reduce existing noise impacts within its parks to
preserve, to the greatest extent practicable, the natural park sounds. The Proposed Action Area is
adjacent to NC 12 and is, therefore, subject to regular noise emissions from vehicles. During
construction activities, a temporary, localized increase in noise generation would occur due to the use
of heavy equipment; however, the soundscape of the project overall would not be noticeably altered.
Therefore, the impact topic of soundscapes was considered, but dismissed from further analysis in this
Environmental Assessment.

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The Village of Avon is a bustling beach com munity, but still maintains a family atmosphere in which
reasonable noise levels are the norm and encouraged by local law enforcement. T he proposed project
area is adjacent to a beach community, commercial activity, and local traffic and is, therefore, subject to
regular noise emissions from vehicles. During construction activities, a temporary, localized increase in
noise generation would occur due to the use of heavy equipment; however, the soundscape of the project
overall would not be noticeably alter ed. Once the project is completed over the course of a few months,
the soundscape would return to its normal levels. Therefore, the impact topic of soundscapes was
considered, but was dismissed from further analysis in this EA.
7.2.8 Noise
On shore, noise levels in the proposed project area are relatively low. No commercial or industrial
activities that create increased ambient noise levels exist in the project are a. Generally, noise levels near
the Avon beach are those associated with public use. Fo r example, additional noise may be generated from
vehicle and foot traffic to and from the pier , or local pier fishing, or beach surfing contests. T he residential
nature of ocean shoreline areas generally equates to low ambient noise levels (USACE 2010). Offshore
noise associated with dredging operations may trigger avoidance reactions in coastal wildlife and
particularly marine mammals reliant on sound for navigation and communication. Reine et al (2014)
found that the frequency and peak pressure of noi se generated during dredging varies , depending on the
type of dredge. Because sound plays an important role in the marine environment for certain species,
potential impacts of elevated sound levels are addressed for a number of species that may be present
in the project area including birds, whales, and sea turtles.
7.2.9 Lightscapes
In accordance with NPS Management Policies (NPS 2006), the National Park Service strives to preserve
natural ambient lightscapes and other values that exist in the absence o f manmade light. The Proposed
Action would not change lightscapes within the Action Area upon completion, and therefore the impact
topic of lightscapes is dismissed from further analysis in this EA.
Construction activities would temporarily impact lightsc apes in the active work area as a result of the likely
need to work 24/7 during a limited period of time when offshore dredging is feasible in the Avon project
area. Construction lighting at night is subject to OSHA regulations (CFR 1926.56). Because of the potential
impacts of construction lighting on threatened and endangered species, the USFWS has prescribed certain
mea sures if these species are present in the project area. These include the prescribed use of certain types
of lighting on the beach an d instructions for directing lights in particular ways to minimize impacts . More
detail on light minimization is provided in Appendix E–Biological Assessment. The proposed project
would not change lightscapes within the project area upon completion, and t herefore the impact
topic of lightscapes is dismissed from further analysis in this EA.

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7.2.10 Infrastructure
No Seashore infrastructure is located within the immediate boundaries of the proposed project area.
Therefore, infrastructure is dismissed from further analysis. Park operations include certain monitoring and
managing of threatened and endangered species, including patrols along the beach to locate and mark
nests. These activities are expected to continue during and after the Proposed Action and to be a key means
of minimizing impacts of the project by establishing no -work buffers and providing additional monitoring
beyond that which is proposed by the Applicant. Following the completion of construction, park operations,
with respect to endangered species monitoring, are expected to remain the same, albeit along a wider beach
with potentially more habitat area to consider. (See Appendix B for a complete discussion of monitoring
shorebird and sea turtle nests and relocating sea turtle nests.) The potential impact of the Proposed Action
on park operations was considered but dismissed from further analysis.
7.3 Public and Private Need
The proposed project is expected to mitigate erosion and provide continued access to a viable recreational
beach for the benefit of the public at large. The proposed project will also increase storm protection which
will provide benefits to public and private properties, help preserve the tax base of the community, and
reduce public expenditures after storms. These benefits will extend over multiple years and are consistent
with the applicant’s long-term strategy to monitor and maintain the beach using defined erosion (or beach
condition) thresholds. No additional public or private needs are identified and, therefore , the topic
of public and private need is dismissed from further analysis in this EA.
7.4 Unresolved Conflicts as to Resource Use
No unresolved conflicts related to the proposed project have occurred.
7.5 Extent/Permanence of Beneficial and/or Detrimental Effects
Detrimental effects are expected to be minimal and short -term. Beneficial effects are expected to be of
high value with project life up to five years. Many of these are discussed in Appendix E‒Biological
Assessment (see Table 11.2), and Appendix F‒Essential Fish Habitat Assessment regarding the impacts on
federal and state protected species.
Assuming the preferred alternative is approved, the applicant acknowledges that disruptions within the
environment would occur and the implementation of certain environmental protection measures would
be needed during the “Preferred Alternative‒Beach Nourishment with Summer Construction.” However,
upon completion of construction, the environmental effects would be beneficial due to the project’s
greater longevity and higher volume of sand, which would produce a wider, longer -lasting beach. “Beach
Nourishment with Summer Construction” is considered the safest and most efficient alternative and , over
the lon g-term, provides the most environmentally beneficial remedy for maintaining a healthy beach.

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8.0 CONSIDERATION OF CUMULATIVE IMPACTS
8.1 Geographic Scope for Cumulative Effects Assessment
A 2.5-mile length of oceanfront beach fronting the Village of Avon and beginning at the south boundary
with undeveloped Seashore area encompasses the project limits. The project area is bounded by the
foredune crest and the edge of the nearshore shelf at −24 ft NAVD. Its northern boundary is ~4,000 lf north
of Avon Pier. Avon is located near the downcoast end of the primary littoral cell between Cape Henry at the
mouth of the Chesapeake Bay and Cape Hatteras (~120 miles of oceanfront with similar exposure to waves from
the northeast). It is also situated near the south end of the secondary littoral cell bounded by Oregon Inlet and
Cape Hatteras (~45 miles). The primary and secondary littoral cells constitute the geographic limits for
consideration of the cumulative impacts of the proposed project.
8.2 Identify/Describe the Direct and Indirect E ffects
On shore in the project area, direct effects would be the construction activity itself. A pipeline from the
offshore dredge would be positioned on the beachface, where it would pump and place sand onto the
beach. Land-based equipment would move and shape the sand to create a new beach profile. These areas
would be marked off where beachgoers would not be able to pass. However, this would be short -lived as
the pump and fill operation completes a section and moves to the next fill area. Shorebirds would easily
relocate from the construction area, finding another stretch of shoreline for resting and foraging . Infauna
or benthic surf zone prey, such as sand crabs and beach hoppers, who live in the wet sand wo uld likely be
disrupted and/or buried by construction, but would rapidly recover.
Offshore dredge operations in the borrow areas w ould cause direct effects from water turbidity , but these
would be short-term as sediments would settle quickly once activit y stopped in the area . Many benthic
organisms would be destroyed by excavation or burial, but studies have shown that benthic assemblages
tend to experience recovery soon after project completion, measured in weeks to month s (USACE 2001,
CZR–CSE 2014). Another possible direct effect from dredge operations would be the presence of
endangered species in the borrow area such as sea turtles, manatees, or whales. However, endangered
species monitors/observers positioned on dredges would alert the dredge operator of any such specie s
spotted . Should one of these species be observed, mitigation procedures would immediately go into
effect, and the dredge would stop operations or relocate.
Immediately after project completion, the direct effects would be a newly restored beach of up to ~1.0
million cubic yards that will be placed, then shaped to form a new beach profile across the foreshore .
Dunes along portions of the Avon oceanfront that have been lost to erosion w ould be rebuilt by land-based
equipment with sand pushed up to create a larger volume of sand along the former dune alignment or as
landward as practicable . The beach w ould equilibrate over a few weeks to months, stabilizing the profile
and providing improved storm protection. The volum e of sand placed on the beach would be designed to
last up to five years along a majority of the project area before the profiles return to the pre -nourishment
condition.

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During operations, indirect effects would include construction impact s on noise levels, soundscapes, and
visual aesthetics, increasing noise levels in the immediate area , and blemishing scenic vistas of the beach
and shoreline. All would be temporary and cease with the completion of the project. Indirect effects will
be seen in improved shorefront for beach activities and improved habitat, especially for migrating
shorebirds and nesting loggerhead sea turtles. Surveys w ould be conducted annually to monitor the
performance of the beach and to measure the cumulative effects of the project.
8.2.1 Potential Effects on Species of Concern (MBTA, MMPA, State-Protected)
Section 6.4 , Appendix E (Biological Assessment), and Appendix F (Essential Fish Habitat Assessment) provide
a detailed discussion of the potential effects of the proposed project . Following is a summary of findings
with respect to the primary species of concern.
Colonial Waterbirds (Caspian Tern, Gull-billed Tern, Common Tern, Least Tern, Black Skimmer ) — The
proposed project would have direct, site -specific, short-term, negligible to minor impacts to foraging or
resting birds which may be in the area.
Wilsons’s Plover — The proposed project would have short -term adverse impacts during construction and
potentially long-term beneficial effects due to the addition of dry beach hab itat.
American Oystercatcher — The proposed project would have short -term adverse impacts during con-
struction and potentially long -term beneficial effects due to addition of dry beach habitat.
Bald Eagle — The proposed project would have a negligible impact during sand placement including
short-term, elevated noise levels. Long -term impacts would be imperceptible, but favorable with the
addition of new beach foraging habitat.
Peregrine Falcon — The proposed project would have short -term, negligible-to-minor impacts during
sand placement operations limited to the immediate area of active construction. Long -term impacts
would be minor, but beneficial with the addition of expanded beach foraging habitat.
Marine Mammals (e xcluding ESA species) (dolphin spec ies, pilot whales) — The proposed project will pro-
duce direct, minor, local and short -term adverse impacts due to construction noise. However, the noise
associated with operating dredges is unlikely to exceed Level A o r Level B thresholds (see Section 6.4.1.6).
Long-term impacts would be neutral.
Diamondback Terrapin (state-protected species) — No adverse impacts are likely to occur to diamond -
back terrapin because its habitat is back barrier areas landward of the foredune.
Seabeach Knotweed (state-protected species) — No adverse impacts are likely to occur to seabeach knot -
weed because there is currently no known occurrence of the plant.

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8.2.2 Potential Effects on Threatened and Endangered Species (see Section 6.4.3)
Piping Plover — The closest docu mented nest occurred on Cape Point approximately six miles south of
the proposed project. However, the piping plo ver utilizes the project beach for roosting, and therefore,
the project will produce minor, short -term, adverse impacts to the species. With an abundance of similar
habitat nearby and the limited sections of shoreline under construction at any particular time, the direct
and indirect impacts are considered insignificant with preferred habitats nearby. Upon completion of the
project, the long-term impacts will be beneficial due to the construction of a wider beach.
Roseate Tern — Due to rarity of appearance in the proposed project area, no direct or indirect impacts to
this species are expected.
Rufa Red Knot — The proposed project will produ ce minor, short-term, adverse impacts to the species,
because it is likely to be present from April through June foraging in the surf zone and roosting on the
beach. However, with an abundance of similar habitat nearby and limited sections of shoreline un der
construction at any particular time, the direct and indirect impacts are considered insignificant. Upon
completion of the project, the long -term impacts will be beneficial because of a wider beach.
Atlantic Sturgeon — The p roposed project is likely t o adversely impact the Atlantic sturgeon as a result of
its possible year -round presence near the borrow areas. Direct effects could include noise, turbidity, tem -
porary interruption of access to food sources, accidental collision with hopper dredge, and potential loss
of foraging habitat. Indirect effects could include changes in the marine nearshore bottom habitat. The
USACE will initiate formal Section 7 consultation with NMFS for the Atlantic sturgeon. The applicant antici -
pates incorporating protec tive measures, including ESA species observers onboard dredges, as required
under the 2020 SARBO.
Shortnose Sturgeon — Because the species is rarely documented within the marine habitats of the project
area, the proposed project may impact, but is not lik ely to adversely impact the shortnose sturgeon.
Seabeach Amaranth — The project may impact, but is not likely to adversely impact the seabeach ama -
ranth. Additions of new dry -sand beach would potentially have a beneficial effect on the propagation of
seabeach amaranth.
Whales — The proposed project may impact, but is not likely to adversely impact, any protected whale
species with the potential to occur in the project vicinity. The species most likely to be within the geo -
graphic limits of the propose d project (northern Outer Banks littoral cell) would be the right whale. Noise
and collisions with ships are the primary concern. Endangered species observers will be stationed on the
dredge(s), maintain lookout for whales in the project area, and trigge r avoidances as required under terms
and special conditions of the permit.
Sea Turtles — The proposed project may impact, and is likely to adversely impact nesting , female sea
turtles on the beach , or other sea turtles in nearshore waters. The USACE will initiate formal Section 7
consultation with NMFS for swimming sea turtles and with USFWS for nesting , female sea turtles on the
beach. The 2020 SARBO from NMFS will be utilized for any take which might occur.

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8.2.3 Potential Effects on EFH, HAPC, or L ife Stages of Associated Managed Fish
Increased development of barrier islands and increased erosion of low -lying, barrier-island segments with-
out adequate dunes have resulted in dredging (both inlet maintenance and excavation of offshore sites)
and beach placement of dredged sediments as common practices in coastal North Carolina. Out of 326
miles of ocean shoreline in North Carolina , 86 miles (~26 percent) have been nourished at least one time ,
and an estimated total of 163 miles (50 percent) have eithe r received nourishment or are being considered
for nourishment sometime in the future (unpublished data, NCDENR 2014). The proposed project is
included in this latter category. The average renourishment interval has been 4.4 years for NC projects.
This means that in a given year, ~6 percent of the NC coast has been subject to beach reconstruction over
the past several decades. The construction duration of nourish ment for any single project is typically ~3–
4 months.
Considering only nearshore waters wit hin state limits, the primary littoral cell to Cape Henry (VA) encom -
passes ~360 square miles (~230,400 acres). The secondary littoral cell is ~135 square miles (~86,400 acres).
Relative to these areas and assuming an average impact width of ~800 ft alon gshore, the footprint of the
proposed project (filling) represents ~0.38 square miles (~245 acres) or ~0.1 percent of the littoral and
nearshore zone within the primary cell. Borrow area totaling a maximum of ~250 acres represents <0.1
percent of the prim ary nearshore waters under consideration.
Several other beach nourishment projects have occurred or are ongoing between Cape Henry and Cape
Hatteras, including:
1) Encompassing 10 miles of shoreline —Nags Head (NC), a locally -sponsored nourishment
project (2 011 and 2019). A limited post-storm restoration project under FEMA funding will add
~0.5 million cy along an assumed ~4 -mile length of shoreline in 2022.
2) Encompassing ~8.9 miles of shoreline —Virginia Beach (VA), an authorized federal project
(2002), and Sandbridge (VA), a locally-sponsored, then federally sponsored project (1998,
2003, 2007, 2013, 2020 ).
3) Encompassing ~ 2 miles of shoreline —Rodanthe (NC), an NCDOT/USACE nourishment project
(2014).
4) Encompassing 7.9 miles of shoreline —Duck, Kitty Hawk, Kill D evil Hills, and the taper of Kitty
Hawk, Southern Shores (NC), a locally-sponsored nourishment project (2017) with
renourishment planned for summer 2022 .
5) Encompassing 2.9 miles of shoreline —Buxton (NC), a locally-sponsored nourishment project
(2017–2018) and a planned renourishment in summer 2022 or summer 2023, depending upon
dredge availability.
6) Encompassing ~2.5 miles of shoreline —Avon (NC) a locally-sponsored project, constituting the
present planned nourishment for summer 2022 or summer 2023, depending upon dredge
availability.
Combined with the Avon project area, these projects represent ~3 4.2 miles (28.5 percent) of the primary
length of shoreline from Cape Henry to Cape Hatteras. The average du ration between nourishment events

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along the Outer Banks and Virginia Beach is likely to be higher than the historical duration , which appears
biased by the relatively high frequency of nourishment at the beaches of Wrightsville, Carolina, and Kure
since the 1960s (USACE 2010). Northern Outer Banks (and Virgini a Beach) nourishment projects were
relatively rare before 2010. Dare County has developed a plan for assisting Outer Banks communities with
nourishment on a five-year schedule , and the Avon area may be on a de facto ~4–5-year schedule , pending
funding availability and performance of the initial project . Assuming the average renourishment schedule
is a five-year cycle, the average length of shoreline impacted in a given year is expected to be ~7 miles or
~6 per cent of the primary littoral cell. This esti mate will increase incrementally if additional Outer Banks
communities, such as Pine Island (Currituck County), elect to restore eroded beaches in the future. A n
increase of the average length of shoreline being nourished each year to ~12 miles or 10 perc ent of the
primary shoreline is considered realistic over the course of the next several decades due to anti cipated
impacts of erosion, sea-level rise , and historical development situated close to the foredune.
Potential effects to marine resources (including food sources and various life stages) or their habitats from
dredging or placement of sediments may include some or all of the following :
 Reduced food availability
 Direct habitat removal or burial
 Increased water-column turbidity
 Dissolved-oxygen reduction
 Contaminant and nutrient release
 Character changes in benthic sediment
 Character changes in benthic composition of infauna
 Suspension and dispersion of infauna
 Entrainment
The potential effect varies from project to project and is dependent o n methods, frequency, season, loca -
tion, and the marine resource s present in the project area.
Over the past few decades, improved dredging methods, equipment, and techniques, improved project
design, sustained interagency collaboration and coordination, the establishment of sediment criteria,
regional planning, and specific permit conditions have all contributed to the minimization of these
potential effects. Largely due to these improvements and collaboration for their NEPA process and
permitting, the USACE–Wilmington District has determined that most beach nourishment projects in North
Carolina can now be properly evaluated with a detailed Environmental Assessment/Finding of No Signifi -
cant Impact (EA/FONSI), instead of an environmental impact statement (Raleigh Bland, USACE–SAW
Regulatory Office, pers comm, 8 August 2017).
EFH and HAPC — Table 6.5 listed the EFH categories and geographically defined HAPCs within the pro-
posed project area or vicinity and , with the exception of Cape Hatteras shoals , only those categories/fea-
tures in the Impact Activity columns in that table which have designations other than N (for no potential
impact) are discussed below with emphasis on the SAFMC resource specifically designated within that EFH

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USACE–Wilmington District (NC) 200 Avon Village, Dare County (NC)
or HAPC. USACE (2013) contains descriptions of both cutterhea d and hopper dredge equip ment, potential
sedimentation and turbidity effects from their operation, and a summary table of minimization measure s
extracted from the final EFH a ssessment for the Emergency Beach Fill Along NC Highway 12 in Rodanthe,
Dare County, North Carolina (USACE 2013 —Sections 13.1 –13.2 and Table 4). For additional details on
differences between dredge types and the summary of various placement methods to reduce impacts,
please refer to Section 5 or USACE (2013).
While the purpose of this assessment is to address project-specific impacts to EFH/HAPC, a suite of large -
scale dynamics and changes in relationship patterns across trophic levels of the southeastern US Atlantic
coastal environment attributed to climate change are also likely to impact EFH/HAPC in various ways and
at an unknown pace. Natural long -term variability in the region and response to such larger scale drivers
is not well understood , but obviously large -scale oscillations in oceanic ci rculation influence oceanog-
raphy. Among other noted climate changes which impact EFH/HAPC (e g – increases in temperature, sea
level, and acidity), the Gulf Stream also appears to be weakening along with its associated Atlantic Merid -
ional Overturning Cir culation (AMOC), which may have implications for primary and secondary produc -
tivity if this weakening results in a decline in duration, magnitude, or frequency of Gulf Stream -associated
upwelling events [per S Rahmstorf et al (2015) in NOAA 2017].
Sargassum — Pelagic sargassum is positively buoyant and, depending on the prevailing surface currents,
remains in waters of the continental shelf for extended periods or can be cast ashore when storm currents
and wind allow such onshore/nearshore transport. There fore, pelagic sargassum species could drift
through the vicinity of the dredge operation in the proposed borrow area or, depending on wind and
currents, could drift into the nearshore or surf zone. Because it occurs in the upp er few feet of the water
colu mn, it is not subject to direct effects f rom dredging, although sediment -placement activities
associated with the proposed project could introduce temporary turbidity in the shallow water column
during sand place ment. However, this turbidity is short -lived and will likely duplicate storm conditions;
thus, no impacts are expected to this EFH or its associated managed fish species. If floating mats are
encountered during dredging or are washed ashore during sand placement and are buried, these mats
would represent a very small portion of this EFH or HAPC available.
Since sargassum occurs in the upper few feet of the water column and is not commonly found in the project
area, the project is not expected to have any impact on this EFH or HAPC or the life stag es of managed
species that utilize them. A ny impacts that may occur are expected to be minor and within
acceptable limits.
Marine Water Column — Dredging and sand placement activities conducted during project construction
will occur in the marine water co lumn in the immediate vicinity of the borrow area and the target beach,
which have the potential to impact nearshore and intertidal surf zone resources of both larval, juvenile,
and/or adult life stages of both predator and prey. These impacts may include minor and short-term
sediment plumes (and related turbidity) as well as the release of trace constituents from the sediment.
Marine sediments can be sinks/reservoirs for various pollutants most typically sourced to atmospheric or
riverine deposition.

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USACE–Wilmington District (NC) 201 Avon Village, Dare County (NC)
Regarding sediments that may be released into the water column during dredging or sand placement
activities in connection with beach nourishment projects, trace constituents are usually associated with
the following: source sediment having proximity to either an active or old port, wastewater treatment
facilities, effluents from industries, or undocumented spill of pollutants. Additionally, nutrients can
accumulate in various soft -bottom sediments and be reintroduced into the water column when disturbed.
Although it could possibly contain constituents from an unknown spill, the proposed borrow area is within
a naturally formed, relict underwater beach ridge located at a considerable distance from a port, inlet, or
known effluent source, so it is unlikely the proposed project would release harmful contaminants or
nutrients during dredging or sand-placement activities. The borrow area is regularly exposed to waves
>10 ft and generally exhibits only trace amounts of fine -grained clays to which contaminants can a dsorb.
Other effects from turbidity in the water column would include changes in light penetration and visibility
which may be either beneficial or problematic (whether predator or prey) and can interfere with nutrient
availability for fil ter feeders. B ecause the proposed borrow area consists of >99 percent sandy or
gravelly material, settling of sediments placed into suspension during dredging operations is expected
to be rapid and measured in minutes, returning the borrow area to ambient conditions soo n after
cessation of opera tions.
Turbidity in the water column from beach placement of sand may create localized, stressful habitat
conditions and may result in the temporary displacement of fish and other biota. Given the high -energy
offshore environmen t and the coarse sediment composition, the turbidity plume created is expected to
be of limited aerial extent and short -lived. Coarse sediments have much higher settling velocities than
finer material (Table 8.1). Fine -grained sediments (such as silts an d clays) produce greater and longer -
lasting turbidity plumes, which can impact large areas of the sea floor more than coarser, sand -sized
material (USACE 2002 a ). Suspended sediments settle at predicted rates depending on grain size as
shown in Table 8.1.
TABLE 8.1. Sediment settling velocities. The mean diameter of sediments for the
proposed project fall in the range of 0.29 –0.42 millimeters (mm). [ds – sieve diameter.
dv – volume sphere diameter. df – sedimentation diameter. *Wentworth
Classification ]
ds
(mm)
dv
(mm)
df
(mm)
@ 10°C
(m/sec)
@ 20°C
(m/sec)
*Sand
Classification
0.089 0.10 0.1 0.005 0.007 vf
0.126 0.14 0.14 0.010 0.013 vf-f
0.147 0.17 0.16 0.013 0.016 f
0.208 0.22 0.22 0.023 0.028 f
0.25 0.25 0.25 0.028 0.033 f-m
0.29 0.30 0.29 0.033 0.039 m
0.42 0.46 0.40 0.05 0.058 m
0.59 0.64 0.55 0.077 0.084 c
0.76 0.80 0.70 0.100 0.110 c
1.25 1.40 1.00 0.15 0.160 vc
1.8 1.90 1.20 0.17 0.170 vc

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The time necessary for sediments in the turbidity plume to settle whether in suspens ion from dredge
activity, in the slurry itself, or resuspended during manipulation is also affected by current and wave
climate in the borrow area during dredge activity and in the intertidal zone during placement and manipu -
lation. While turbidity plumes associated with dredging are often short -lived and may affect relatively
small areas, subsequent resuspension and redispersal of dredged sediments can be propagated beyond
the dredged area for extended periods in certain wave climates (CSA International et al 2010). However,
these effects are minimal in sandier offshore areas like the proposed borrow area.
The impacts from turbidity associated with the proposed project may be similar, on a smaller scale, to the
effects of storms. Storm effects also genera lly include increased turbidity and suspended sediment load
in the water column and, in some cases, changes in fish community structure (Hackney et al 1996). Severe
storms have been associated with fish kills, but such situations are not associated with b each disposal of
dredged sand. Turbidity will be most noticeable in proximity to the slurry discharged from the pipe head
which operates ahead of the beach -building activities. The section of beach affected per day will vary from
800 ft to 1,000 ft in le ngth with ~200 –300 ft per day as the estimated completion rate. Elevated turbidity
levels were detecte d within up to ~500 ft down -current of the discharge point along Nags Head during the
2011 project (CSE 2012). The discharge plume was generally not det ectable at greater distances. The
nearby Buxton 2018 project utilized similar sediments and demonstrated similar rapid reduction in
turbidity several hundred feet from the discharge point.
Van Dolah et al (1994) assessed turbidity conditions associated wi th a beach nourishment project at Folly
Beach (SC), where the native mean grain size is ~0.2 mm, and drew the following conclusion:
Although dredge effluent does increase turbidity levels in the immediate vicinity of the outfall, there
are many other facto rs such as local weather and wave energy that will also produce this effect. The
turbidity levels at Folly Beach during nourishment and the dispersal of the sediment plume were not
considered unusual or severe relative to normal fluctuations and background levels.
In their environmental r eport on the “Use of Federal Offshore Sand Resources for Beach and Coastal
Restoration in New Jersey, Maryland, Delaware and Virginia ” (MMS 1999), the US Department of Interior –
Bureau of Ocean Energy Management (BOEM) (previously MMS) provided the following assessment:
In order to assess if turbidity causes an impact to the ecosystem, it is essential that the predicted
turbidity levels be evaluated in light of conditions such as during storms. Storms on the Mid -Atlantic
shelf may generate suspended matter concentrations of several hundred mg/L (e.g., Styles and Glenn
1999). Concentrations in plumes decrease rapidly during dispersion. Neff (1981, 1985) reported that
solids concentrations of 1000 ppm two minutes after discharge decreased to 10 ppm within one hour.
Poopetch (1982) showed that the initial concentration in the hopper overflow of 3,500 mg/L
decreased rapidly to 500 mg/L within 50 m. For this reason, the impact of the settling particles from
the turbidity plume is expected to be minimal beyond the immediate zone of dredging.
Burlas et al (USACE 2001) fou nd that certain fish species (e g – kingfish) were attracted to higher turbidity
waters, whereas other species (eg – bluefish) avoided high turbidity wate r around the discharge pipe

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during a major nourishment project along the central New Jersey coast. This study indicates that fish may
seek as well as avoid locally turbid water associated with beach nourishment and that the presence of
elevated turbidity can repel, or even attract, certain species dependent upon their particular adaptive
behavior. In addition to USACE (2001), other studies have also found insignificant impact or even a
temporary increase in surf zone fish populations associat ed with nourishment projects as possibly
attributed to:
1) Release of nutrients and infauna during dredging .
2) Wide-foraging nature of surf zone fish . or
3) Short-term stay of migratory fish in the pro ject area (Deaton et al 2010).
So while highly migratory managed species (such as bigeye, bluefin, skipjack, and yellowfin tunas) all are
presumed to be in the waters near Avon , it is unlikely these species will be affected by the associated
turbidity of the proposed project. [N ote: While it is only a representational data set, NCDMF recreational
catch data from 2004 to 2019 show tuna in those intercepts only for private and charter boats , and not in
any beach intercepts including piers.]
Fish larvae in the ocean waters near Oregon Inlet generally trav el westward until they encounter the
shoreline, then migrate along the shoreline until they encounter the inlet (USACE 2002b). As stated in the
EFH assessment prepared for the recent Rodanthe project by th e USACE (2014), results from larval ingress
and egress studies suggest that larval transport from offshore shelves to estuarine nursery habitats occurs
in three stages: (1) offshore spawning grounds to nearshore, (2) nearshore to the locality of an inlet or
estuary mouth, and (3) from the mouth into the e stuary (Boehlert and Mundy 1988).
Results from the Hettler and Hare (1998) study suggest two bottlenecks for offs hore-spawning fishes with
estuarine juveniles: (1) the transport of larvae into the nearshore zone and (2) the transport of larvae into
the estuary from the nearshore zone. While the methods fish larvae use to cover large distances over the
open ocean and find the inlets to their estuarine nurseries is uncertain, both passive and active methods
of movement are suspected along with the use of environmental cues such as salinity, depth, temperature,
swells, etc. Various studies have hypothesized passive wind and depth -varying current dispersal and
active horizontal swimm ing transport. However, data are limited regarding larval distribution in the
nearshore area.
As indicated in USACE (2014), population level calculations of larval entrainment from hydraulic dredging
activities were insignificant within a representative high concentration inlet bottleneck at Beaufort Inlet,
North Carolina. Therefor e, the risk of larval entrainment from dredging activities in the offshore borrow
areas associated with th e proposed project would likely be even less. However, some larvae in the marine
water column adjacent to the beach could be buried or injured during sand placement activities, but not
in numbers that would have a long -term effect at the species level.
Very few peer-reviewed papers have discussed responses of fish larvae or eggs to man-made sounds. While
many other factors may be at play in the responses of juveniles and adults to man -made noise or to any
long-term consequences, one of the most important will be largely determined by the presence or absence

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of a gas bladder (Popper et al 2014). Gas bladders, along with their location within the bod y, make fish
more susceptible to pressure -mediated injury to the ears and other tissues than those without and allow
fish to detect a broader frequency range and at greater distances (Popper et al 2014). Most bony fishes
have gas bladders while the more p rimitive cartilaginous fishes (sharks and rays) do not. Despite recent
interest and increased concern, wide information gaps make it very difficult to draw conclusions about the
nature and levels of man -made sounds and their potential to cause harm on fis h, turtles, or invertebrates
(Hawkins et al 2014).
For the reasons described, marine water column EFH will experience temporary turbidity from both the
dredge operation and the sand -placement activity along with the potential for some fish or benthos
larval death and/or injury from turbidity; however, mobile juvenile and adult fish species have the ability
to locate away from the most disruptive activities. Noise levels may result in avoidance behaviors in
some mobile fish species, but levels are not exp ected to cause hearing damage. Feeding activities of
fish that prey on the benthic invertebrates may be temporarily interrupted, but these interruptions are
considered minor.
Effects of the proposed project are not expected to be long -lasting or cause sig nificant impact to
marine column EFH or the life stages of managed species that are found within this habitat.
Unconsolidated/Shallow Subtidal Bottom (Marine Only) — This EFH is extensive and includes all areas
of submerged or intertidal bottom seaward of the beach not considered hard bottom. This EFH provides
large areas of nursery and foraging grounds for invertebrates and managed fish. Dredging of sediments in
the offshore borrow area will disturb and dislodge benthic organisms and either cause mortal ity from
burial or entrainment or disrupt their normal behaviors during the disturbance window. Beach disposal
of the dredged sediments can affect fishery resources through the burial of intertidal and surf zone
resources that managed fish may utilize.
However, some demersal fish species are sometimes attracted to this type of disturbance and feed on the
numerous fauna that may be suspended in the water column from the dredging or disposal activity. Other
more sensitive demersal species can opt to move aw ay to adjacent feeding areas. While Deaton et al (2010,
364) acknowledge “the relative quick recovery on intertidal and shallow subtidal benthic communities”
associated with soft -stabilization projects on oceanfront shorelines, without adequate best mana gement
practices known to enhance biological recovery, recovery rates in mined areas are usually longer.
While not specifically designated as EFH, HAPC, Primary Nursery Areas (PNAs) or Strategic Habitat Areas,
features called Rippled Scoured Depressions (RSDs) and Rippled Channel Depressions (RCDs) should also be
considered. These are recognized as important soft -bottom habitat, and such features provide a structure
diversity for fish and benthos in the nearshore environment (Deaton et al 2010). As a no urished beach
equilibrates, sediment placed in the targeted nourishment zone could gradually move within these
nearshore RSD/RCD features, which shift seasonally in response to wave action. However, as stated in USACE
(2014), Thieler et al (1999, 2001) de monstrated it is likely that the features would be maintained through the
self-reinforcing pattern in response to both alongshore and across -shore flows independent of beach

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nourishment activities. Therefore, benthic organisms normally associated with fine - and coarse-grained
sediments in the nearshore component of this EFH are not likely to be significantly altered by the project.
Managed species, whether piscivorous or not, are attracted to this EFH largely due to its use by their
preferred food, a proce ss driven by the dynamics of a typical food web which is built from the bottom to
the top and largely dependent on the benthic community in the unconsolidated sediments. Spatial and
temporal variation in the benthic community prey species can therefore af fect growth, survival, popula -
tion levels of predators, and all higher trophic level species (Normandeau Associates 2014). The annual
and seasonal variability in the benthic community of this EFH is well documented, and when subject to
storms during a mon itoring period (hurricanes or nor’easters common to the Outer Banks), project effects
can be difficult to discern with confidence (Deaton et al 2010). However, known factors that maximize
benthic biological recovery rates in the offshore portion of this EFH include use of hopper dredges, shallow
excavation, use of topographic hig hs, and rate of sand movement.
In US Gulf and Atlantic sandy borrow areas studied within BOEM jurisdiction, general faunal recovery (total
abundance and biomass) has been shown to vary from 3 months to 2.5 years; however, paucity of long -
term studies suggest that diversity and dominants composition may take 3.5 years (Michel et al 2013). A
recent longer -term (6- and 8-year) study of offshore borrow areas dredged for two South Caro lina beach
nourishment projects indicated that both borrow areas shifted toward finer sediments post-dredging and
showed little recovery as measured by faunal density, number of species, and changes in composition at
the species level (eg – opportunistic t axa recolonization) (Crowe et al 2016). However, like others, this
study also surmised that dredging depth was a likely factor that contributed to the influx of finer sedi ments
which , in turn , affected the benthic community recovery.
Most offshore borrow sites along the South Carolina coast consist of fine sand (0.15 –0.3 mm diameter) and
are in close proximity to tidal rivers and inlet s with high concentrations of mud in suspension (Van Dolah
et al 1998). Infilling of borrow areas with muddy sediments is more likely at South Carolina sites than in
the proposed project area.
Those factors which maximize recovery in the beach intertidal zone include grain size (similarity between
native beach and borrow source is considered the most important factor), seaso n of nourishment (winter
placement avoids peak recruitment periods), frequency of nourishment (allow s for growth to maturity
across years), location of sediment placement (maintain s stable geomorphology across the normal beach
seasonal profile to ensure sa nd remains in the system as long as possible), and rate of longshore transport
(upstream recruitment opportunity). The Nags Head 2011 project, which was monitored quantitatively for
benthic populations on the beach and in the borrow area, showed n o infilling fines in the borrow area and
accurate placement of properly sized sediment . A full suite of species similar to the native beach and
offshore zone recolonize d the impact areas within one season. By the second year taxa richness and
abundances were similar to controls (CZR –CSE 2014).

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USACE–Wilmington District (NC) 206 Avon Village, Dare County (NC)
In subtidal environments frequently disturbed by natural events, infauna are well adapted to such pertur -
bations by being small -bodied, short-lived, with a maximum rate of fecundity, efficient dispersal mechan-
isms, dense settlement, and rapid growth rates. Burial or temporary exposure from dredging could also
be beneficial or problematic, depending on species and niche. [A more mobile fauna may be able to dig
vertically to the new surface and avoid burial , and less mobile prey species temporarily exposed may pro -
vide more available f ood source for predator species .] However, it is recognized that tube dwellers and
permanent burrow dwellers are most susceptible to these types of disturbances compared to more mobile
organisms.
A study of 50 dredge and disposal projects concluded that benthic recovery measured in months was
associated with shallow, naturally disturbe d habitats, unconsolidated fine -grain sediments, and univari-
ate analytical approaches, while longer recovery (years) was associated with deep stable habitats, sand
and gravel sediments, and multivariate or functional group analytical techniques (Wilber and Clarke 2007).
This same study also noted that absence of both deposit feeders and of mid -depth burrowers may indicate
an area is in a state of recovery. Polychaete worms and crustaceans recover most rapidly (several months)
(Rutecki et al 2014 ), while deep burrowing mollusks are slower and may take several years (Brooks et al
2006). However, while polychae tes comprise the larger component of soft sediment infauna, a complete
life history is known for only about 5 percent of the >8,000 described polychaete species (Ramey 2008).
Additionally, studies have shown that avoidance of the peak larval recruitment pe riod (early spring in the
eastern US) can have a beneficial effect on the recovery rate (Wilber et al 2009)—the Avon nourish ment
project is proposed to occur in the summer. On a spatial scale, which far exceeds the proposed borrow
area, another system dr iver which can affect both s peed and diversity of biological recovery of a post -
disturbance benthic assemblage is variability in supply, transport, and settlement of larvae for some
species (CSA International et al 2010).
While some disturbance, mortality, and burial will occur with dredging and sand placement activi-
ties, these effects are not expected to be long -lasting or cause significant impact to unconsolidated/
shallow subtidal bottom EFH (marine only) or the life stages of managed species which are found
within this habitat.
Nearshore Shoals Habitat — Shore-oblique ridges and shoals are common features in nearshore waters
of the northern Outer Banks (Swift 197 6). Some of the shoals, including Diamond , Kinnakeet, and Wimble,
cover thousands of acres and are recognized for their importance as spawning or nursery areas for finfish
(Deaton et al 2010). The proposed borrow area is situated on or within a similar nearshore shoal and
represents a minute fraction of the same type of habitat found in state w aters between Cape Henry and
Cape Hatteras. Underwater relief of natural shoals off the Outer Banks is of the order 30 ft or more in
comparison with the proposed maximum excavation dept h of 10 ft.
The proposed borrow area, as well as larger named shoal complexes represent low -relief features
characteristic of relict beach ridges (See Fig 1.2). However, the ridge and nearby flatter habitat provide
complexity for some species of fish and inverte brates. Site-specific information about the fish and

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USACE–Wilmington District (NC) 207 Avon Village, Dare County (NC)
invertebrates found within the borrow area was not located, but biological resources which may be
common in the area can be inferred from the offshore benthic data collected for the 2011 Nags Head
project. Any vertical relief can provide refugia for an abundance of potential prey, which then affords more
suitable foraging ground and likely attracts more predators.
A deeper understanding and appreciation for the diversity of demersal and pelagic fishes associated with
shoal complexes has been gained with recent stu dies in the Mid -Atlantic Bight (predominantly north of
Maryland) and support their designation as EFH (eg – pelagics such as bay anchovy, Atlantic menhaden,
Atlantic mackerel, butterfish, striped bass). Potential feeding, spawning, and maturation can take place
in these habitats during fall and spring migrations of numerous managed and unmanaged fish species,
especially those behaviorally and morphologically adapted to bottom feeding in sedimentary environ -
ments (ie – skates, scups, drums, sea robins, black seabass, flounders ) (CSA International et al 2010).
The water depths in the shallowest portion of the borrow area that is proposed to be dredged range from
about 35–40 ft (11–12 m) at the top of the ridge to about 45–50 ft (14–15 m) along the flatter top ography on
the inshore side of the ridge slope. As described in the EFH assessment for the 2014 nearby Rodanthe beach
nourishment project, modeling performed for that project showed that for shoals in similar water depths,
waves more likely influence their formation rather than currents (USACE 2013). However, depths in the
proposed borrow area are at the shallower end of the 33‒100 ft (10–30 m) model range.
Another model suggests that post -dredge infill of borrow areas is largely dependent on whether or not the
ridge is active, whether or not there is sand available for refilling, and the actual dredging location within
the ridge (CSA International et al 2010 ). This model suggests that the best location for dredging on a shoal
or ridge (at least from a physical standpoint ) is the leading, downdrift edge as the borrow scour area can
then be fed by ongoing physical (wave) proces ses which, if active, are presumed to quickly refill the
borrowed area. The ridge crest would be the second -best, followed by the trailing edge. [Note: the
proposed borrow area is considered by the applicant to be favorably positioned for natural infilli ng after
cessation of dredging.] If the ridge is not active, only larger -scale processes (eg – major storms will rebuild
the ridge). The Dibajnia and Nairn (2011) model (referred to in the Rodanthe EFH assessment ) also tested
various dredging methodologies and subsequent reformation scenarios in order to suggest ways to dredge
offshore that would protect and maintain the morphologic integrity of ridge and shoal features; thereby
also affording protection of or reestablishment of benthos and fish habitat.
The proposed borrow area is subject to periods of high waves from the south as well as high waves during
nor’easters. Consequent net shoal migration and the leading edges of the shoal are likely to fluctuate and
be of less significance with respect to the layout of the borrow area excavations (see Appendix D –Littoral
Processes).
Only medium to coarse grain sediment (≥90 percent sand) will be placed on the ocean beach strand in the
Avon project area. Any turbidity with this placement is not expected to extend to nearby named shoals ,
such as Diamond Shoals, which are located south of the proposed project area. However, turbidity
associated with the removal of sediment from the offshore borrow area will have short-term impacts on

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USACE–Wilmington District (NC) 208 Avon Village, Dare County (NC)
the water column in the immediate vicinity and will potentially allow some settlement of fines to the
bottom. The associated turbidity effects from dredging in the proposed borrow area and from sand
placement on the Avon beach will not adversely impact nearby sandy shoals with altered longshore
currents or altered tidal climate.
Dredge operations in the proposed , offshore borrow areas will alter the geometry of the existing sand
feature which can alter benthic species recruitment patterns, especially if the area refills with finer -grained
sediments. However, the effects of these alterations will be minimized by the metho d and location of
targeted cutting, such that portions of the habitat structure unique to the feature and important to
resource use will be maintained. A combination of physical and environmental variables (eg –
temperature, depth, current facing versus l ee side) as well as differences in sampling season or gear type
bias (otter trawl versus beam trawl) all contribute to differences in cr oss-shelf, species assemblage
distributions among research studies of shoals. Studies of shoals in the Mid -Atlantic Bight show most
diversity, taxa richness, and abundance documented from the flats adjacent to shoals . According to
Slacum et al (2010), winter was the period of lowest finfish and invertebrate use of shoal habitat (Diaz et
al 2004, Slacum et al 2010, an d Normandeau Associates 2014).
Vasslides and Able (2008) evaluated shoreface sand ridges as habitat for fishes of the northeast coast and
noted that shoreface sand ridges may have a distinct influence on fish abundance and assemblages. Con -
trary to other stu dies which found higher species richness and abundance in the surrounding inner shelf
habitat (Diaz et al 2004 and Slacum et al 2010), Vasslides and Able noted highest species abundance and
richness on either side of the sand ridge with distinct recrea tionally and commercially important species
assemblages. The fish found at the top of the ridge were typical prey species (sand lances, anchovies,
smallmouth flounder) favored by both resident and transient piscivores in the Mid -Atlantic Bight (Chao
and Musick 1977 , Chase 2002 , Walter et al 2003 , Gartland et al 2006) and, thus, sand ridges may influence
the distribution of these economically important piscivores (Vasslides and Able 2008).
Use of the topographic high and lee flank of the proposed borr ow area , overall shallow excavation depth,
and the location of the borrow site in an area of high sand movement are important factors that will
maximize biological recovery rates (Deaton et al 2010 , CZR–CSE 2014). Further, the area of the proposed
borrow excavations represents <<1 percent of the extant similar habitat available offshore within the
Avon/northern Outer Banks littoral cell .
Therefore, the proposed project is not expected to pose a threat to nearshore shoals EFH or the life
stages of managed speci es which are found within this habitat. Any impacts that may occur are
within reasonable limits.
8.3 Temporal Scope of Assessment
Through surveys planned for summer to fall each year, sand volume changes will be monitored on a
regular basis after project completion. Annual monitoring will be ongoing and published for interested
parties to review .

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8.4 Describe the Affected Environment
Within the primary littoral cell extending from Cape Henry to Cape Hatteras, net sand transport is predomi-
nantly to the south (Inman and Dolan 1989), but reverses along southern Virginia beaches where it is
directed north into the Chesapeake Bight (USACE 2010). The Avon project area is an east-facing beach
within the primary littoral cell. Beaches within the primary littoral cell are exposed to deep-water waves
from the southeast to the north, including some of the highest waves along the US East Coast (Leffler et al
1996).
During Hurricane Irene (2011) and Hurricane Sandy (2012), peak w ave heights about one mile off Duck and
Nags Head exceeded 27 ft (McNinch et al 2012, CSE 2013). While hurricane waves often propagate and
drive sand to the north, more frequent northeast waves produce net southerly transport in the Avon
project area (Inman and Dolan 1989).
Mean monthly wave heights near the proposed project area are ~3.7 ft in July and ~5.6 ft in January (see
Fig 5.2). The mean tide range is 2.99 ft and the spring tide range is ~3.5 ft (source: NOAA). Sea level rose
during the 20th century with the recent tide gauge record showing a 4.3 -inch (~11 cm) rise over 30 years at
Oregon Inlet (NCCRC 2015).
Everts et al (1983) prepared a detailed analysis of shoreline change for the Outer Banks , which researched
measurements of ocean and sound shoreline changes b etween the 1850s and 1980s , and reviewed earlier
maps and charts. This analysis was a cooperative study conducted by the Coastal Engineering Research
Center (CERC) and National Ocean Service (NOS) within USACE and NOAA. Everts et al found that the Outer
Banks, on aver age, was narrowing by ~0.9 m/yr (~3 ft/yr) with the majority of the recession occurring along
the oceanfront [~0.8 m/yr (2.6 ft/yr) average], and the sound shoreline was stable with a net recession of
0.1 m/yr (~0.3 ft/yr) on average. The Everts et al study (1983) theorized that the principal losses of sand
along the Outer Banks are associated with inlets, particularly the deposits of sa nd into the sound.
The Avon project area is vulnerable to natural losses of sand due to variable longshore transport rates
associated with wave refraction and shoaling (see Appendix D – Littoral Processes), as well as sudden sand
losses due to n or’easters and hurricanes. A regular schedule of beach surveys was initiated in 2020, the
first of its kind along Avo n Beach . In preparation for the proposed nourishment, the applicant conducted
condition surveys of the beach in July 2020. The surveys confirmed volumes of sand in the foredune, on
the visible beach, and in the near shore zone out to a depth >40 ft (see Fig 3.1). This analysis identified
which beach segments were critically eroded and provided a measure of sand deficits with respect to a
normal stable beach (see Appendix D–Littoral Processes).
Each nourishment project constructed or planned within the s tudy area will add sediment to the littoral
system. While this sediment remain s mobile, nearly all of the volume would be conserved given the nature
of the sediment quality. Therefore, on a site -specific basis, nourishment at the scale proposed greatly
exceeds the average annual erosion rate along the Outer Banks as repo rted by Everts et al (1983) or the
average volumetric loss -rate as determined by the applicant (see Appendix D) which accounts for recent
accelerated erosion . As nourishment sites lose sa nd, adjacent unnourished beaches tend to benefit over

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time by either a reduction in erosion rates or an increase in accretion rates. To some degree, each
nourishment project in the Outer Banks tends to offset a sand deficit and mitigate erosion somewhere for
many years after its design life for the locality has passed (Dean 2002). Because such effects are widely
spread and incremental, they can onl y be detected via rigorous comparative surveys. However, the impact
can be projected based on simple relatio nships between volumes of nourishment and added beach area.
CERC (1984) reported a typical nourishment impact of one square foot added to the beach for every
cubic yard of sand. Outer Banks projects from 2010 to 2020 have added over 17 million cubic yar ds to
the littoral zone from Duck to Cape Hatteras (~68 miles). If eventually distributed uniformly over this
shore length, the volume would add ~17 million square feet (~390 acres) of beachfront lands. This is
equivalent t o an average widening of ~45 f t, or roughly 15 times the average annual shoreline recession
rate for the Outer Banks measured by Everts et al (1983). A stated long-term strategy of Dare County is
to replace chronic sand losses along Outer Banks beaches and advance the shoreline seaward to create
a protective buffer between the ocean and development. Each planned project contributes to the goal
directly for the community involved and indirectly for neighboring communities and the Cape Hatteras
National Seashore.
8.5 Determine Environmental Consequences
The proposed action is a nourishment project designed to mimic the natural processes of accretion, which
also occur along Hatteras Island at neighboring beaches. The project will reverse the effects of sand loss
and severe erosion and protect the NC Highway 12 , and infrastructure of the Village of Avon , then rebuild
eroded dune s and the beach profile to enhance Avon beach. Additions of sand by artificial means are
generally more impactful than natural additions, because of scale and r ates of change to the profile (ie –
more sand can be placed on the beach in a short period of time to create a wider beach and counter the
effects of erosion). The added sand, if similar in texture to native sand, would be indistinguishable after
the beach equilibrates.
Evidence from the nearby 2017–2018 Buxton nourishment project indicates that few if any harmful effects
resulted from that project. The proposed project seeks to replicate similar features of the 2017–2018
project by using beach-quality sediments and by placing most of the sand in the active littoral zone. T he
cumulative beneficial effects of nourishment would be of high value to the shorebird and sea turtle species
attracted to a wider sand beach. It would also be of great si gnificance t o the local tourism economy and
would fortify real estate values and tax revenues.
8.6 Mitigation to Avoid, Minimize or Compensate for Cumulative Effects
As the proposed project will widen the beach and thus improve species habitat, cumulative effects a re
expected to be positive. Mitigation to avoid, minimize or compensate for cumulative effects related to
project construction would not be needed.

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8.7 Conclusions Regarding Cumulative Impacts
Section 8.2.3 discussed the geographical and physical impa cts of the project on similar habitats betwe en
Cape Henry and Cape Hatteras along with a list of anticipated nourishment projects in the northern Outer
Banks. When all planned or executed projects are considered along the 120 -mile primary littoral cell, s ome
temporal and spatial effects will occur.
It was demonstrated that the frequency of nourishment at any particular locality in Dare County is unlikely
to be more frequent than one event per five years. It was further shown that at this frequency, ~6 percent
of the study area would be impacted for part of any given year (the typical construction duration is 3 –4
months). A doubling of this rate of nourishment due to more communities at risk or higher erosion rates
associated with increasing sea levels a nd storm intensities would potentially involve 10 –12 percent of the
Dare County shoreline in a given year. This would leave ~90 percent of the shoreline out of direct effects
of nourishment in an average year.
It was further demonstrate d that nourishment sediment tends to be conserved in the littoral zone. There -
fore, as nourishment volume is lost over time in a particular project area, it likely contributes to the sand
budget along adjacent, unnourished beaches. This was proven for Cape Point’s east b each which accreted
significantly as a result of downcoast spreading of the 2017 –2018 Buxton nourishment project (CSE 2019 c).
Thus, indirect effects of the Avon nourishment would be positive and expand along shore into undeveloped
Seashore beaches over time. The principal benefit is the addition of beach area and dune habitat with a
concomitant reduction of storm damages . An improved and maintained beach tends to reduce the
installation of emergency sand bags to protect vulnerable property.
The borrow area proposed for the Avon nourishment is not unique habitat along the Outer Banks and
likely constitute s <1 percent of similar bottom habitat within state waters. The percentage of similar
offshore area would be substantially less if federal waters are i ncluded.
8.7.1 Potential Cumulative Effects of the Proposed Project on Species of Concern
Section 6.4 discussed the species of concern (MBTA-, MMPA-, state-protected), potential impacts of the
proposed project on those species , and the possible cumulative impacts for which all known or planned
projects in the study area are considered. This subsection repeats the conclusions given in Section 6.4
with respect to probable cumulative impacts.
MBTA-Protected Species
Colonial Waterbirds (Gull-billed Tern, Caspian Tern, Common Tern, Least Tern, Black Skimmer) — Habitat
loss or degra dation due to human activities associated with recreation or development elsewhere in Dare
County would continue. However, the proposed project would provide up to five years of w ider beach
availability for bird use. W hen added to the cumulative effects of the four 2022 northern Outer Banks
nourishment projects, construction of the NCDOT fly-over bridge (Rodanthe), periodic Oregon Inlet dredging,
and continued development in Dare County—the incremental adverse impact on colonial waterbirds of the

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“No-Action Alternative” is imperceptible, and impacts are imperceptible to noticeable for “Preferred
Alternative–Beach Nourishment With Summer Construction.”
Wilson’s Plover — Under the proposed project , impacts to nesting and foraging habitat would occur and
individual birds may be disturbed during construction, but these are considered negligible, temporary,
and short-term, and would not likely adversely impact Wilson’s plover. Sand that migrates from the nour-
ished beach downdrift within the littoral current would feed the existing foraging and roosting habitat along
the Seashore, a potential long-term benefit to the species. The incremental adverse impacts on Wilson’s
plover of either of the two evaluated alternatives are imperceptible when added to the cumulative adverse
effects of the four 2022 northern Outer Banks nourishment projects, construction of the NCDOT fly-over
bridge, periodic Oregon Inlet dredging, and continued developme nt in Dare County.
American Oystercatcher — The proposed project would have the short -term potential to adversely
impact nesting birds, but may provide beneficial impacts to nesting habitat due to a wider beach. Overall,
the American oystercatcher is not likely to be adversely impacted by the project. The incremental adverse
impacts on American oystercatcher are imperceptible when added t o the cumulative effects of the four 2022
northern Outer Banks nourishment projects, construction of the NCDOT fly-over bridge, periodic Oregon Inlet
dredging, and continued development in Dare County.
Bald Eagle — The bald eagle would not likely be adversely impacted by the proposed project. The incre -
mental adverse impacts to bald eagle are imperceptible when added to the cumulative adverse effects of
the four 2022 northern Outer Banks nourishment projects, construction of the NCDOT fly-over bridge,
periodic Oregon Inlet dredging, and continued development in Dare County.
Peregrine Falcon — Habitat loss or degradation due to human activities associated with recreation or
development elsewhere in Dare County would continue , but the proposed project would provide
beneficial impacts of a wider dry beach use d by shorebirds which are prey for peregrine falcon. The
incremental adverse impacts to peregrine falcon of either of the two evaluated alternatives are
imperceptible when added t o the cumulative effects of the four 2022 northern Outer Banks nourishment
projects, construction of the NCDOT fly-over bridge, periodic Oregon Inlet dredging, and continued
development in Dare Cou nty.
MMPA-Protected Species
Marine Mammals — The proposed project has the potential to temporarily affect certain behaviors of
some species, particularly avoidance of sounds generated by dredging activi ties, and may adversely
impact marine mammals. The incremental adverse impacts to marine mammals are imperceptible when
added to the cumulative adverse effects of the four 2022 northern Outer Banks nourishment projects,
construction of the NCDOT fly-over bridge, periodic Oregon Inlet dredging, noise from ocean-going vessels,
and offshore exploration for oil and gas.

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State-Protected Species
Diamondback Terrapin — No adverse impacts are likely to occur to the diamondback terrapin. The
negligible potential impacts to the diamondback terrapin due to the proposed project are imperceptible
when added t o the cumulative effects of four 2022 northern Outer Banks nourishment projects and other
development and infrastructure activity continuing in Dare County.
Sea beach Knotweed — Habitat loss or degradation due to human activities associated with recreation or
development elsewhere in Dare County would continue. Considering the lack of historic occurrence in the
proposed project area, it would be unlikely for seab each knotweed to be adversely impacted by either of
the two evaluated alternatives. The incremental adverse impacts to seabeach knotweed of either of the two
evaluated alternatives are imperceptible when adde d to the cumulative effects of the four 2022 northern
Outer Banks nourishment projects, construction of the NCDOT fly-over bridge, periodic Oregon Inlet dredging,
and continued development in Dare County.
8.7.2 Endangered and Threatened Species (ESA-Protected)
This subsection repeats the conclusions given in Section 6.4 with respect to probable cumulative
impacts. (See Appendix E‒Biological Assessment , Section 9.1 .)
Piping Plover — Upon completion of the project, the piping plover would potentially benefit from
increasing roosting area produced by a wider beach. However, the piping plover is considered highly
sensitive to climate change, development, construction activities, increased frequency of storms, and
increased beach use. Therefore, the proposed project may affect and is likely to adversely affect the piping
plover.
Roseate Tern — Impacts and cumulative impacts to the roseate tern would be similar to those of the
piping plover. However, the roseate tern is rarely observed in the proposed project area and, therefore,
cumulative impacts are expected to be unmeasurable when added to other planned nourishment projects
in Dare County and increased beach use by visitors.
Rufa Red Knot — Impacts and cumulative impacts to the rufa red knot would be similar to those of the piping
plover. The decline in species population is linked to climate change and the commercial harvest of
horseshoe crab in Delaware Bay. When combined with development activities and other beach nourish ment
projects in Dare County, the Proposed Action may affect and is likely to adversely affect the rufa red knot.
Atlantic Sturgeon — Climate change, overfishing, and dams on spawning rivers all have the potential to
affect the Atlantic sturgeon. Dredging op erations could potentially result in an incidental take because
the borrow area is situated ~16 miles from Hatte ras Inlet and ~30 miles from Oregon I nlet, which are key
pathways between ocean waters and spawning grounds. Therefore, the proposed project may affect and
is likely to adversely affect the Atlantic sturgeon.

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Shortnose Sturgeon — Because it is rarely documented within the aquatic marine ha bitats of the
proposed project a rea, the project may affect, but is not likely to adversely affect the shortnose sturgeon.
Seabeach Amaranth — Beach nourishment activities could potentially impact seabeach amaranth if it
were present, but the plant has not been documented within the proposed project area and therefore is
unlikely to be affected. Coastal development and encroachment on habitat by increased human recrea -
tional use of the dry beach will continue to have adverse cumulative effects on seabeach amaranth.
However, the construction of a wider beach will potentially increase the area of unvegetated, dry-sand
habitat favored by the species. The proposed project may affect, but is not likely to adversely impact, the
seabeach amaranth .
Whales — The North Atlantic right whale is the species with the highest likelihood of being in the vicinity
of the dredge activity. All other whale species, including finback whales, are not expected to utilize waters
in the immediate vicinity of the proposed project. Marine mammal observers will be stationed on board
dredge(s) to alert crews to take evasive action and suspend work to avoid collisions.
Cumulative effects to the finback and North Atlantic right whales would include the continuation of current
threats , such as ensnarement in commercial fishing gear, overfishing of prey species for human or animal
food sources, habitat degradation , and noise. When added to the noise generated by seismic testing/sur -
veys in ocean waters from Delaware to Florida as part of oil/gas exploration activities and by pile -driving
associated with construction of offshore wind turbine clusters on the western Atlantic continental shelf,
noise from dredging operations may be cumulatively detrimental, even if it does not cause measura ble
injury. Effects of the proposed project are considered to be insignificant or discountable; therefore, the
proposed project may affect, but is not likely to adversely affect, any protected whale species with the
potential to occur in the project vicin ity.
Sea Turtles — Turtle populations are adversely impacted by clima te change (eg — sea level rise, inunda-
tion, nest temperatures, and sex ratios), a decline of seagrass beds, steadily encroaching human develop -
ment, and nuisance lighting. The proposed project will add incrementally to these cumulative impacts,
both in the water column (potential takes by hopper dredge) and on the beach (interfere with nesting
activities). Minimization measures will be followed including onboard sea -turtle monitors and beach
monitors (all nests will be relocated prior to construction) to reduce the likelihood of lethal take on the
beach and in nearshore waters . However, there is a likelihood that an incidental take could occur ,
especially for the loggerhead. Therefore, the proposed project may affect and is likely to adversely affect
nesting female sea turtles on the beach or other sea turtles in the nearshore waters. The USACE would
initiate formal Section 7 consultation with USFWS for nesting sea turtles and with NMF S for swimming sea
turtles. The 2020 SARBO from NMFS is expected to be utilized for any take which m ight occur .
8.7.3 Potential Cumulative Effects of Proposed Project on EFH and HAPC
Recent nearby nourishment projects have occurred in f ive other Dare C ounty towns or villages, including
Duck, Kitty Hawk, Kill Devil Hills, and Buxton in 2017, and Nags Head in 2019 . A short segment of Southern

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Shores is included in the project at Kitty Hawk (September 2017). Prior to 2017, NCDOT’s 2014 Rodanthe
emergency nourishment occurred ~16 miles north of the Avon Pier. The long length of beach between
Rodanthe and Avon tends to be relatively healthy, posing little immediate threat to NC 12 or community
infrastructure in that area. Depending on how time -crowded or space-crowded future offshore dredging
and beach placement operations would be, cumulative effects could be harmful to managed fishes and
their habitats (marine water column, sargassum, Cape Hatteras shoals) within the borrow area and/or the
surf zone. Dare County government has been developing a long-range beach nourishment plan that will
eventually schedule and coordinate beach segments in need of sand into a five -year rotation to ensure
more equitable use of available county funds. Such a staggered and coordinated approach should reduce,
either spatially or temporally, the negative cumulative effects of multiple projects which occur in close
proximity.
As post-nourishment beach invertebrate population recovery appears to be most sensitive to the similarity
between native and introduced sediments, N orth Carolina adopted sediment criteria for beach nourish -
ment projects in the state. Geological models of shoal formation offshore have shown that as long the
seafloor irregularity remains on which to reform a ridge, dominant shelf processes will reconstruct these
features as predicted by the shelf -ridge process models despite repeated dredge episodes from the crest,
leading-edge, or trailing edge (CSA International et al 2010). Along with strict adherence t o NC sediment
criteria, additional offshore dredging and sand -placement mitigative practices for beach nourishment
projects will also minimize the potential of cumulative effects to the EFH and HAPC.
With the high quality of the sediment selected for sand placement, little to no int erruption to long-
shore or cross -shore sediment transport dynamics, one -time-only strategic removal of shoal sands
from designated borrow areas , and the small amount of soft bottom, marine water column, or sandy
shoal in the proposed project area relative to the amount of available other similar EFH or HAPC at
any time, the proposed activity would not be expected to pose a significant cumulative threat.

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9.0 CONSERVATION AND MITIGATION MEASURES
9.1 Avoidance and Minimization
When considering effects on waters of the United States due to the proposed project—overall, there would
be no effect , and in the offshore borrow areas and dredge operation areas, there would be li ttle effect as
a result of the project . The presence of dredges offshore of the proposed project area would cause
temporary disturbance of the waters and borrow area sediments. This disturbance would be short -lived
and would change with the dredge reloca tion. If marine species are observed by the on-site dredge moni-
tor, the operator would follow mitigation measures to relocate or stop operations until the species has left
the area. Other mitigation is provided through the professional operation standar ds followed by reputable
and experience d dredge operators.
If the USACE decides to permit th e proposed project, then avoidance and minimization measures would
be incorporated into the terms and conditions of the USACE federal permit as outlined in subsect ions
1.3.1., 5.2.3, and as described intermittently in species effects determinations in Sections 6, 8, and 10.
See Section 1.3.2 and Appendix B (Monitoring & Mitigation Measures ) for a detailed listing of endan -
gered species monitoring and environmental protection measures that the applicant anticipates
implementing during construction. An overarching goal is to produce:
 A nourished shoreline with similar slopes, sediments, and morphology as the existing
shoreline
 No trace of disturbance by heavy equip ment when restoration efforts are complete d
The proposed project will comply with all hopper -dredge protocols as outlined under the existing SARBO.
Currently, no minor project modifications are known to be needed during the preparation of this EA.
9.2 Compensatory Mitigation
Compensatory mitigation is not required to offset environmental losses resulting from proposed unavoid -
able impacts t o waters of the United States.
The remainder of this section does not apply.

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10.0 COMPLIANCE WITH OTHER LAWS, POLICIES, AND REQUIREMENTS
10.1 Section 7(a)(2) of the Endangered Species Act (ESA)
The applicant ’s “Preferred Alternative–Beach Nourishment with Summer Construction” in the proposed
project area would potentially impact threatened or endangered species. Accordingly, the applicant pre-
pared a Biological Assessment (BA) (Appendix E) and an Essential Fish Habitat (EFH) Assessment
(Appendix F) in connection with the proposed project. The USACE, as the lead federal agency for the
proposed Avon project, will initiate Section 7 consultation with the US Fish and Wildlife Service (USFWS),
National Marine Fisheries Service (NMFS), and other federal and state resource agencies. Und er Section 7
consultation, USFWS or NMFS may authorize an incidental take through a Biological Opinion for ESA -
protected species that are likely to be adversely affected by the project activities. Officials at USFWS and
NMFS have been involved in pre -application meetings and have had opportunities to provide input prior
to completion of the BA and EA.
10.1.1 Other Agency Documented Compliance
No other federal agency has taken steps to document compliance with Section 7 of the ESA.
10.1.2 Consultation with NMFS and/or USFWS
Consultation with NMFS and USFWS w as initiated and will be completed a s part of the EA review process.
In support of the nearby 2017–2018 Buxton nourishment project, Dare County submitted a BA (CSE 20 15a)
and received the Biological Opinion (BO) (USFWS 2016 ). The proposed Avon nourishment project involves
highly similar habitats and species impacts; therefore, the experience with the Buxton project and the
successful implementation of environmental protection measures is expected to increase the likeli hood
of an incident-free project. Following in Table 10.1 is a matrix of species as they will or will not be impacted
by the “No Action Alternative ” and the “Preferred Alternative -Beach Nourishment with Summer
Construction”.

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TABLE 10.1. (6 pages) Effects matrix summary for the three alternatives addressed in this EA for ESA-protected, other federally
protected, and/or state protected species with the potential to occur, and proposed mitigation to offset adverse effects.
Resource No-Action
Alternative
Alternative 2
Winter Construction
Preferred Alternative 3
Summer Construction
EASTERN BLACK RAIL

Present year round on
NC Outer Banks but
mostly north of Oregon
Inlet and rare in project
area

Existing breeding, foraging, or
resting habitat in back barrier
areas could be reduced by
inlet breach should one occur.
Temporary-short term, negligible
disruption from noise from project
activities for the rare individuals
who may be in the back barrier
habitats in vicinity.
Temporary-short term, negligible
disruption from noise from project
activities for the rare individuals
(more in summer than winter but
still rare) who may be in the back
barrier habitats in vicinity.
PIPING PLOVER

Present year round on
NC Outer Banks; nests in
Seashore near tidal
inlets or overwash areas;
no nests in project area.
No effect to existing breeding,
foraging, or resting habitat.
Potential beneficial effect
should a breach occur and
new tidal inlet habitat form.
Potential beneficial effect if
future overwash events build
new breeding, foraging, or
resting habitat. No adverse
effect to critical wintering
habitat.
Temporary-short term, negligible
disruption of foraging areas.
Foraging habitat could be affected
although historically project area is
low quality foraging habitat. Any
plovers resting in the project area
during construction would be
temporarily displaced. No adverse
effect to critical wintering habitat.
Potential beneficial long term
effect to resting habitat (wider dry
beach) and foraging habitat (lower
slope intertidal beach) and critical
wintering habitat by downcoast
migration of nourishment
sediment.
Temporary to short term,
negligible disruption of foraging
areas; but not likely to adversely
affect. Foraging habitat could be
affected although historically
project area is low quality foraging
habitat. No nesting habitat within
the project area. Any plovers
resting in the project area during
construction would be temporarily
displaced. No adverse effect to
critical wintering habitat.
Potential beneficial long term
effect to resting habitat (wider dry
beach) and foraging habitat (lower
slope intertidal beach) and critical
wintering habitat by downcoast
migration of nourishment
sediment.

MITIGATION: Prescribed NPS
surveys for use of the beach by
piping plovers will occur into mid-
August and include the project area.
No construction will occur within
any NPS established buffers.
ROSEATE TERN

No nesting habitat or
breeding occurs at
Seashore; rare visitor
during migration May
through Sep. Jul records
within Seashore.
No effect to breeding, foraging
or resting habitat. Negligible
effect to resting habitat.
No effects to breeding, foraging, or
resting habitat. Negligible effect to
resting habitat. Beneficial short
term effect to resting habitat
(wider dry beach).
Temporary to short term,
negligible disruption of resting and
foraging areas for the rare visitor;
but not likely to adversely affect.
Any birds resting in the project
area during construction would be
temporarily displaced. Beneficial
long term effect to resting habitat
(wider dry beach).
ROSEATE TERN

No nesting in North
Carolina; birds have
been observed in all
months in Seashore with
highest numbers during
peak migration in Apr-
May and Aug-Sep.
No effect to foraging or resting
habitat.
Temporary, negligible effect but
not likely to adversely affect.
Foraging habitat could be affected
although historically project area is
low quality foraging habitat.
Beneficial long-term effect to
resting habitat (wider dry beach)
and foraging habitat (lower slope
intertidal beach).

Temporary, negligible, minor
adverse effect. Foraging habitat
could be affected although
historically project area is low
quality foraging habitat. Beneficial
long-term effect to resting habitat
(wider dry beach) and foraging
habitat (lower slope intertidal
beach).

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Resource No-Action
Alternative
Alternative 2
Winter Construction
Preferred Alternative 3
Summer Construction
ATLANTIC STURGEON

Documented in project vicinity
waters most all year; moves to
freshwaters inshore to spawn
in spring.
No adverse effect. Potential
beneficial effect if inlet breach
opens new access to Pamlico
Sound habitats. Duration of
benefit would depend on
NCDOT response or length of
time inlet remained open.
Temporary, negligible to minor
effect due to potential disruption
in early spring during inshore
migration.
MITIGATION: Conservation
measures to minimize impacts or
disruption provided by NMFS
during consultation will be
followed. Qualified NMFS/PRD
approved endangered species
observer on dredge at all times
who will follow standard
reporting procedures and has
authority to stop dredge ops if
Atlantic sturgeon observed in
area of danger or in dredge
screen, skimmer funnels or drag
heads.

Temporary, negligible to minor
effect due to potential disruption
in late spring during inshore
migration.
MITIGATION: Conservation
measures to minimize impacts or
disruption provided by NMFS
consultation will be followed.
Qualified NMFS/PRD-approved
PSO on dredge at all times would
follow standard reporting
procedures and would have
authority to stop dredge ops if
Atlantic sturgeon observed in
area of danger or in dredge
screen, skimmer funnels, or drag
heads.
SHORTNOSE STURGEON

Move to freshwater from late
winter to early spring; remains
in estuarine and nearshore
waters remainder of year. One
record from Pamlico Sound.
No effect. Potential beneficial
effect if inlet breach opens new
access to Pamlico Sound
habitats. Benefit duration
depends on how long inlet
open and NCDOT response.
Temporary, negligible to minor
adverse effect due to potential
disruption in late winter or early
spring during migration to fresh
and estuarine waters.
Temporary, negligible to minor
effect due to potential disruption
in nearshore waters but not
likely to adversely affect.
GIANT MANTA RAY

Errant individuals could be
present in most any month but
usually in deeper oceanic
waters associated with
upwelling.

No effect. Temporary, negligible to minor.
Noise avoidance could affect
feeding behavior depending on
presence of prey species.
MITIGATION: Qualified NMFS/
PRD-approved PSO on dredge at
all times would follow standard
reporting procedures and has
authority to stop dredge ops if a
giant manta ray is spotted in area
of danger.

Temporary, negligible to minor.
Noise avoidance could affect
feeding behavior depending on
presence of prey species
MITIGATION: Qualified NMFS/
PRD-approved PSO on dredge at
all times would follow standard
reporting procedures with
authority to stop dredge ops if a
giant manta ray is spotted in area
of danger.
SEABEACH AMARANTH

No plants documented in the
Seashore since 2005; no
records from project area.
Long-term, moderate effects to
potential habitat. Beach would
eventually become too narrow
to support; alternatively,
regular overwash would
increase potential habitat.
Temporary, negligible to minor.
Potential beneficial long term
effects (wider beach above
wrack line).
MITIGATION: NPS biologists, who
survey for the plant each year,
would notify if found. If found,
steps to avoid the plant(s) will be
identified by NPS manager
coordinating with USFWS
biologists.

Temporary, negligible to minor.
Potential beneficial long term
effects (wider beach above
wrack line).
MITIGATION: NPS biologists. who
survey for the plant each year,
would notify if found. If found,
steps to avoid the plant(s) will be
identified by NPS manager
coordinating with USFWS
biologists.

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USACE–Wilmington District (NC) 222 Avon Village, Dare County (NC)

Resource No-Action
Alternative
Alternative 2
Winter Construction
Preferred Alternative 3
Summer Construction
WEST INDIAN MANATEE No adverse effects. Beneficial
effect if breach inlet formed to
provide additional access to
inshore/sound foraging areas.
No effects. Species not typically
present in winter.
MITIGATION: Qualified NMFS/
PRD-approved PSO on dredge at
all times would follow standard
reporting procedures and has
authority to stop dredge ops if a
manatee is spotted in area of
danger.
Temporary, negligible to minor
adverse effects. Noise avoidance
could affect behavior.
MITIGATION: Qualified NMFS/
PRD- approved PSO on dredge at
all times would follow standard
reporting procedures with
authority to stop dredge ops if a
manatee is spotted in area of
danger.
WHALES

Fin and humpback migrate
through the western Atlantic in
winter, North Atlantic right
migrate through in spring and
are found closer to shore in
spring but can be in project
vicinity throughout the winter
months. Blue whales have
been documented closer to
shore (winter only) than once
expected but no strandings
have been documented in
NC 1997-2020. The 2020
SARBO issued No Effect
determinations for blue, fin,
sei, and sperm whales when all
pertinent PDC’s are followed,
particularly vessel speed
reduction.
No effects. Temporary, negligible to minor
effects. Noise avoidance could
affect behavior of winter
migration. The 2020 SARBO
determination is that the
Proposed Action may affect but
is not likely to Adversely Affect
the North Atlantic right whale
during winter migration.
Similarly, the Proposed Action
May Affect but is Not Likely to
Adversely Affect the humpback
whale which is unlikely to be
observed in shallow waters.
MITIGATION: Qualified NMFS/
PRD-approved PSO on dredge at
all times would follow standard
reporting procedures and has
authority to stop dredge ops if a
whale is spotted in area of
danger.
Temporary, negligible to minor
effects. Noise avoidance could
affect behavior of any whales
present. The Proposed Action
during the applicant’s preferred
summer construction window
will align with the NMFS
determination of Not Likely to
Adversely Affect the North
Atlantic right whale, which
migrates near the area in other
seasons. The Proposed Action
may affect but is not likely to
adversely affect the humpback
whale.
MITIGATION: Qualified NMFS/
PRD- approved PSO on dredge at
all times would follow standard
reporting procedures and has
authority to stop dredge ops if a
whale is spotted in area of
danger.
SEA TURTLES

(includes green, hawksbill,
Kemp’s ridley, leatherback,
and loggerhead)
Some commonly nest in
Seashore; others never to
rarely, but may be present in
project vicinity waters.
Long-term, moderate adverse
effect to nesting habitat.
Beach would eventually
become too narrow to support
nesting. Regular overwash
would decrease nest success.
Potential beneficial short term
effect if breach occurred which
would allow new temporary
access to back barrier habitats
until the breach closed. A
potential NCDOT solution to a
breach may include a
temporary bridge which may
have short term adverse effect
to turtles in the area during
construction.
No effect during construction.
Project would occur outside of
the sea turtle nesting season. No
adverse effect on critical
migratory habitat. Nesting
beaches would have long term
beneficial effect (wider beach
and lower slope).
Temporary, negligible to minor;
likely to adversely affect.
Nesting females could be
disturbed in project area. No
adverse effect on critical
migratory habitat. Nesting
beaches would have short-term
negligible effect but beneficial
long-term effects (wider beach
and lower slope).
MITIGATION: No night work or
only night work w/turtle friendly
lighting; night-time monitors
must survey the affected beach
area on any given night before
the required 9 am daily survey.
Nesting surveys initiated by 15
April for leatherback and 1 May
for others. Surveys would

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Resource No-Action
Alternative
Alternative 2
Winter Construction
Preferred Alternative 3
Summer Construction
SEA TURTLES (concluded)

continue during project by trained
experienced personnel, duly
authorized and permitted by
agencies. Construction would not
begin until the daily survey was
completed in any given area. All
nests in project area to be
relocated by NPS personnel as
soon as possible after discovery
(no later than 0900) to a location
to ensure hatch success. Nests
discovered after project
completion in an area will not be
relocated if laid in location
conducive to hatch. All in-situ or
relocated nests must be marked
with stakes to delimit a 10-foot
buffer zone around the nest, two
on-beach markers, and must be
monitored daily. Qualified NMFS/
PRD- approved PSO on dredge at
all times would follow standard
reporting procedures and has
authority to stop dredge ops if a
sea turtle is spotted in area of
danger.

MARINE MAMMALS
(other than those above)

Four species common to
abundant in project vicinity;
three of which are present year
round.

No adverse effect. Beneficial
effect from breach inlet (new
access to back barrier sound
and river habitats) for species
which seek such areas.
Temporary, negligible to minor
potential adverse effect during
dredge and pumping activity.
Common bottlenose dolphin
most likely to be affected by
noise from project construction.
Temporary, negligible to minor
potential adverse effects during
dredge and pumping activity.
Common bottlenose dolphin
most likely to be affected by
noise from project construction.
COLONIAL WATERBIRDS

(includes gull-billed tern,
common tern, least tern,
Caspian tern, and black
skimmer)
All nest on NC beaches
including Seashore and within
project area. As a group, can
be in project area from March
to Nov.

Long-term, moderate adverse
effect to nesting habitat as
beach would eventually
become too narrow to support
nesting. Breach inlet would
provide new foraging and
resting habitats.
No effect. Birds not normally
present in winter. Beneficial long
term effect to nesting habitat
(wider beach).
Temporary to short term,
negligible to minor effect to
nesting birds and disruption of
foraging and resting areas.
Beneficial long term effect to
nesting habitat (wider beach).
MITIGATION: NPS surveys and no
construction within 300 meters of
active colonies.

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Resource No-Action
Alternative
Alternative 2
Winter Construction
Preferred Alternative 3
Summer Construction
AMERICAN OYSTERCATCHER

Common in Dare County all
year with low numbers in
winter months. Nests and
breeds in Seashore.

Long-term, moderate
adverse effect to nesting
habitat. Beach would
eventually become too
narrow to support nesting.
No effect. Species not normally
present in this area during
winter. Beneficial long term
effect to nesting habitat (wider
beach).
Temporary to short term,
negligible to minor effect to
nesting birds and foraging and
resting areas. Beneficial long-
term effect to nesting habitat
(wider beach).
MITIGATION: NPS surveys and
no construction within 300
meters of active nests or chicks.

WILSON’S PLOVER

Rare nester in Seashore;
present March to October
with occasional Jan or Nov
occurrence.
Long-term, moderate
adverse effect to nesting
habitat. Beach would
eventually become too
narrow to support nesting.
No nests in project area but a
few nests have been
documented elsewhere at
Seashore.
Temporary to short term,
negligible disruption of
foraging and resting areas.
Temporary, negligible, minor.
Foraging habitat could be
affected; historically, project
area is low quality foraging
habitat. Beneficial long-term
effect to resting habitat (wider
dry beach) and foraging habitat
(lower slope intertidal beach).
MITIGATION: NPS surveys and
no construction within 300
meters of active colonies.

PEREGRINE FALCON

No nesting along NC coast;
uncommon May to Aug; more
common in Oct. Winter
resident.
No effect to breeding or
resting habitat. Potential
beneficial effect to foraging
habitat if inlet breach occurs.
Temporary to short term,
negligible adverse effect from
disruption of foraging areas.
Beneficial long term effect to
foraging and resting habitat
(wider dry beach).
Temporary to short term,
negligible adverse effect
from disruption of foraging
areas. Beneficial long term
effect to foraging and
resting habitat (wider dry
beach).

BALD EAGLE

No nests in project area;
birds observed all months in
Seashore, but more common
in winter.

No effect to breeding,
foraging, or resting habitat.
Temporary to short term,
negligible adverse effect from
disruption of foraging and
resting areas
Temporary to short term,
negligible adverse effect from
disruption of foraging and
resting areas.

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10.1.3 Effects Determination for ESA-Protected Species
Of the federally listed species with the potential to occur in the proposed project area or vicinity shown in
Table 10.1, evaluation of the effects of the proposed project resulted in a May Effect, not Likely to Adversely
Affect conclusion for five species (roseate tern, seabeach amaranth, finback whale, north Atlantic right
whale, and shortnose sturgeon), and a May Effect, Likely to Adversely Affect conclusion for eight species,
including five sea turtles (Kemp’s rid ley, green, leatherback, logger head, and hawksbill), the Atlantic
sturgeon, piping plover, and red knot . As mentioned in Appendix E‒Biological Assessment, Section 9.4, the
2020 SARBO from NMFS is expected to be utilized for the sea turtles. Section 7 consultation will be initiated
and USFWS and NMFS will respond with their Biological Opinion and Incidental Take Statement(s) as
applicable (USFWS-species on land; NMFS-species in water). Table 10.2 is a summary of the determination
of the effects for those 13 species.

State Protection Only
Resource
No-Action
Alternative
Alternative 2
Winter Construction
Preferred Alternative 3
Summer Construction
DIAMONDBACK TERRAPIN

Nests and forages in marsh or
back dune areas; hibernates
in back-barrier muds. No
record from within project
activity area.
Long-term, unpredictable,
moderate effects to existing
potential habitat. Overwash
could bury nests, young, or
adults and habitats, but may
increase and build habitats
further into the sound
overtime which could be
beneficial. A breach may
destroy habitat if inlet became
permanent.
No effects. Temporary, negligible to minor
effects due to potential
disruption when crossing NC 12;
such disruptions already occur
from existing traffic. Project
related traffic would be
temporary and mostly confined
to the beach where the turtle is
not found.
SEABEACH KNOTWEED

Unpredictable colonizer
species found between wrack
line and foredunes and
overwash fans. No record
from within project footprint,
but documented in project
vicinity (near the Cape
Hatteras Lighthouse).
Long-term, unpredictable,
moderate effects to existing
potential back-barrier habitat
(existing foredune habitat not
suitable). Overwash could
bury seeds and habitats, but
may increase brackish and
back barrier habitat or assist
in seed dispersal which could
be beneficial.
Temporary, negligible to minor
effects. Potential beneficial long
term effects (wider beach).
MITIGATION: NPS biologists
survey for the plant each year
and will notify if found.
Temporary, negligible to minor
effects. Potential beneficial long
term effects (wider beach).
MITIGATION: NPS biologists
survey for the plant each year
and will notify if found.

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TABLE 10.2. Summary effects determination of ESA-protected species with the potential to occur in
project area or vicinity.

SPECIES FEDERAL/
STATE STATUS DETERMINATION
Birds
Eastern black rail T/PT NO EFFECT
Piping plover T/T MAY AFFECT, NOT LIKELY TO ADVERSELY
AFFECTRoseate tern E/E MAY AFFECT, NOT LIKELY TO ADVERSELY
AFFECTRed knot T/T MAY AFFECT, NOT LIKELY TO ADVERSELY
AFFECTCaspian tern T MAY AFFECT, NOT LIKELY TO ADVERSELY
AFFECTCommon tern MBTA/E MAY AFFECT, NOT LIKELY TO ADVERSELY
AFFECTLeast tern MBTA/SC MAY AFFECT, NOT LIKELY TO ADVERSELY
AFFECTGull-billed tern MBTA/T MAY AFFECT, NOT LIKELY TO ADVERSELY
AFFECTBlack skimmer MBTA/SC MAY AFFECT, NOT LIKELY TO ADVERSELY
AFFECTAmerican oystercatcher MBTA/SC MAY AFFECT, NOT LIKELY TO ADVERSELY
AFFECTWilson's plover MBTA/SC MAY AFFECT, NOT LIKELY TO ADVERSELY
AFFECTBald eagle BEGEPA/T MAY AFFECT, NOT LIKELY TO ADVERSELY
AFFECTPeregrine falcon MBTA/E MAY AFFECT, NOT LIKELY TO ADVERSELY
AFFECTFishes
Atlantic sturgeon E/SC MAY AFFECT, LIKELY TO ADVERSELY AFFECT
Shortnose sturgeon E/E MAY AFFECT, NOT LIKELY TO ADVERSELY
AFFECTGiant manta ray T MAY AFFECT, NOT LIKELY TO ADVERSELY
AFFECTPlants
Seabeach amaranth T/T NO EFFECT
Seabeach knotweed E NO EFFECT
Mammals
Fin whale E MAY AFFECT, NOT LIKELY TO ADVERSELY
AFFECTHumpback whale E MAY AFFECT, NOT LIKELY TO ADVERSELY
AFFECTNorth Atlantic right whale E MAY AFFECT, NOT LIKELY TO ADVERSELY
AFFECTBlue whale E MAY AFFECT, NOT LIKELY TO ADVERSELY
AFFECTWest Indian manatee T/T MAY AFFECT, NOT LIKELY TO ADVERSELY
AFFECTMarine mammals (other)MMPA MAY AFFECT, NOT LIKELY TO ADVERSELY
AFFECTReptiles
Green sea turtle T/T MAY AFFECT, LIKELY TO ADVERSELY AFFECT
Hawksbill sea turtle E MAY AFFECT, NOT LIKELY TO ADVERSELY
AFFECTKemp’s ridley sea turtle E/E MAY AFFECT, LIKELY TO ADVERSELY AFFECT
Leatherback sea turtle E/E MAY AFFECT, LIKELY TO ADVERSELY AFFECT
Loggerhead sea turtle T/T MAY AFFECT, LIKELY TO ADVERSELY AFFECT
Diamondback terrapin SC NO EFFECT

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10.2 Magnuson-Stevens Fishery Conservation and Management Act, Essential Fish Habitat
As a condition of any federal permits for the proposed project, the applicant would follow the
requirements of the USACE to consult with the National Mar ine Fisheries Service (NMFS) under the Marine
Mammal Protection Act (MMPA), the Magnuson-Stevens Fishery Conservation and Management Act
(MFCMA), Coastal Zone Management Act (CZMA), Coastal Barrier Resources Act (CBRA), and other
NEPA/environmental requirements.
10.2.1 Other Agency Document Compliance
No other federal agency has taken steps to document compliance with the EFH provisions of the
Magnuson-Stevens Act.
10.2.2 Review Required Under Magnuson -Stevens Act
The proposed project require s review u nder the Magnuson-Stevens Act. For a full report, see Appendix F
–Essential Fish Habitat Assessment.
The applicant notified the NOAA –Southeast Regional Office (SERO) in spring 20 21 about the proposed
Buxton project and informed the agency that an Essential Fish Habitat (EFH) Assessment (Appendix F) was
in preparation. Alth ough both SAFMC and MAFMC manage numerous fish stocks, only those which have a
federal Fishery Management Plan (FMP) have designated Essential Fish Habitat.
The applicant also has commun icated with the Atlantic States Marine Fisheries Commission (ASMFC).
Since 1942, ASMFC has been the deliberative body of the Atlantic coastal states, and it coordinates the
management and conservation of 25 nearshore fish species. Some of these 25 specie s are also managed
by either SAFMC or MAFMC. Many of these species are included in the EFH and/or Habitat Areas of
Particular Concern (HAPC) addressed in Appendix F‒Essential Fish Habitat Assessment.
10.2.3 Effect Determination
The proposed Avon nourishment project would not be expected to cause any significant adverse impacts
to EFH or HAPC for those species managed by SAFMC and MAFMC. Coordination with represen tatives of
NMFS and NCDMF will continue throughout the life of the project in order to ensure that all parties are
aware of any fisheries impacts. Additionally, both NMFS and NCDMF will be provided with information
from any required project surveys, and the development of detailed borrow area use plans will be
coordinated with both agencies.
The following EFH considerations were developed in coord ination with the NCDMF and NOAA –NMFS, and
will be implemented for the proposed Avon nourishment project to the maximum extent practicable:
 Promote quick benthic recovery through shallow borrow area excavation .
 Use topographic highs and/or areas of high sand movement within offshore borrow areas.
 Encourage dredge operations that leave behind unimpacted "ridges" to allow for recovery .

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 Avoidance of hard bottom resources (within the nearshore toe of fill and offshore borrow
area).
 Construction of a temporary berm during placement on the beach strand in order to
minimize turbidity.
These will be integrated into the Avon project construction process in order to minimize physical and
biological impacts to EFH and to assure that any adverse effects are short -term and localized on both an
individual and cumulative effects basis.
10.2.4 Consultation with NMFS
On behalf of Dare County (via a pre-application interagency meeting on 4 March 2021), the applicant
notified the NOAA Southeast Regional Office (SERO) about the proposed Avon nourishment project and
informed the agency that an Essential Fish Habitat Assessment (Appendix F) was in preparation. The
applicant consulted SERO’s webpage and used it to generate the list of species to evaluate. The USACE
will continue NMFS coordination required to receive concurrence on the analysis of the effects on EFH and
conservation/mitigation recommendations included in this EA.
Although both SAFMC and MAFMC manage numerous fish stocks, only those with a federal FMP have desig-
nated EFH. While no official coordination is required with ASMFC —since 1942, it has been the deliberative
bod y of the Atlantic coastal states and coordinates the management and conservation of 27 Atlantic
coastal fish species or species groups. Some of these 27 species/groups are also managed by either SAFMC
or MAFMC and many also utilize EFH and/or HAPC address ed in this EA.
Coordination with representatives of NMFS and NCDMF will continue throughout the life of the project in
order to ensure that all parties are aware of any fisheries impacts. Additionally, both NMFS and NCDMF
will be provided with information from any required project surveys , and the development of detailed
borrow area use plans will be c oordinated with both agencies.
10.3 Section 106 of the National Historic Preservation Act (NHPA)
As a condition of any federal and state permits, t he Applicant has consulted with the NC State Office of
Historic Preservation (SOHP) (organized within NCDNCR) regarding the proposed project in the project
area for the proposed nourishment project. The applicant will draw on its previous experience working
with SOHP when applying for permits for the nearby 2017–2018 8 nourishment project. In consultation
with Tidewater Atlantic Research (TAR) of Washington (NC), the applicant would advise SHPO of potential
cultural resources located by TAR that ma y be present or impacted in the general vicinity of the project.
(TAR 2021).
10.3.1 Known Cultural Sites Present
The Avon offshore area is part of the infamous “Graveyard of the Atlantic ,” which has claimed up to 5,000
shipwrecks since first recorded in the 1700s . Previous exploration of underwater cultural resource s has

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USACE–Wilmington District (NC) 229 Avon Village, Dare County (NC)
documented over 190 shipwrecks offshore of Dare County. The earliest known shipwreck, James E
Newsome, occurred before 1728. For the 2017 –2018 nourishment project, surveys were conducted by
Tidewater Atlantic Research Inc (TAR –Washington NC) to locate previously unidentified cultural sites.
A submerged cultural resource remote -sensing survey of the proposed borrow area was conducted by
Tidewater Atlantic Research (TAR) of Washington, North Caro lina. Field work was completed by 24 July
2021, and the results and findings are included in Appendix G - Cultural Resources Survey of this
Environmental Assessment. Work performed by TAR consisted of a background literature survey,
historical research, and cartographical investigation. Field investigations identified three magnetic
anomalies inside the proposed borrow area, and three within the 200 -ft perimeter of the borrow area. All
six anomalies represent very small ferrous objects. None appear to represent a potentially significant
submerged cultural resource and therefore, no avoidance was recommended. Analysis of the acoustic
data identified no evidence of sonar targets in the borrow area or its immediate vicinity. Consequently,
no potentially significant submerged cultural resources will be impacted by dredging in the proposed
borrow area or its adjacent 200 -ft buffer.
Data generated by the cultural resources survey does not identify any historical shipwrecks or other
submerged cultural resourc es. However, in the event that any project activities expose potential
prehistoric or historic cultural material, the dredging company should immediately shift operations away
from the site and notify the representatives of the USACE, the North Carolina S tate Historic Presentation
Office (SHPO) in Raleigh (NC), the Underwater Archaeology Branch (UAB) in Kure Beach (NC), the
Application (Dare County), and the Engineer (CSE). Notification should address the exact location, where
possible, the nature of mate rial exposed by project activities, and options for immediate archaeological
inspection and assessment of the sites.
10.3.2 Effect Determination on Cultural Resources
Regarding cultural resources onshore, the proposed project would not affect the placement and dune-
building operation because no resources have been identified for the project area on the beach.
The applicant rates the project as having a “minimal adverse effect” on cultural resources in the
waters where the dredges are loca ted as buffer zones would be established to prevent dredging near
any identified resources.
10.4 Tribal Trust Responsibilities
Secretarial Order 3175 requires that any anticipated impacts on Indian Trust resources from a proposed
project or action by US Department of the Interior agencies be explicitly addressed in environmental
documents. A consultation was not conducted with a f ederally-recognized t ribe, because the regulated
activity (ie – the proposed project ) will not affect protected tribal resour ces and tribal rights
including treaty rights and Indian lands . While the Outer Banks area was populated by many native
Indian tribes when first explored in the 1600s, most tribes either migrated east, were killed by

JULY 2021 Environmental Assessment
USACE–Wilmington District (NC) 230 Avon Village, Dare County (NC)
white settlers, or died from European -imported diseases. Of the eight state or federally recognized
Indian tribes in North Carolina, none are currently located in the Outer Banks area
(https://americanindiancenter.unc.edu/resources/faqs -about-american-indians/), and the lands
comprising the p ark are not held in trust by the Secretary of the Interior for the benefit of Indians due to
their status as Indians. In addition, no tribes claim significant historical or cultural resources in the
proposed Avon project area.
Previous experience with the nearby 2017–2018 Buxton nourishment project confirmed that no
tribal resources have been found in th e project vicinity and the same result is expected for the
proposed Avon nourishment project. Therefore, the proposed project would not affect tribal trust
resources, treaty rights, or lands.
10.5 Section 401 of the Clean Water Act – Water Quality Certification (WQC)
The NC Department of Environment al Quality’s Division of Water Resources (NCDE Q–DWR) administers the
Clean Water Act Section 401 Certifica tion. The NCDWR must review the proposed project and issue a 401
Certification prior to state or federal permits for construction involving dredge and fill in navi gable waters
of the United States . As defined by the Clean Water Act (CWA), the proposed project impacts the waters of
the United States and is , therefore, subject to review by the USACE.
A Section 401 WQC is required for the proposed nourishment project and w ould be issued as part of
the NC Coastal Area Management Act (CAMA) requirements . Certification would be issued in the future
after the project progresses further in the review process .
10.6 Coastal Zone Management Act (CZMA)
The proposed project will b e considered as a package by USACE and other federal and state agencies. For
coastal management, the proposed project w ould be reviewed under the NCDEQ–NCDCM. NCDCM
administers CAMA and must review the proposed project prior to issuance of a major CAMA permit. NCDCM
requires a permit application and supporting documents under NEPA in parallel with a federal permit
application. NCDEQ is the overall coordinating state agency responsible for soliciting review and comment
on the proposed project from relevant state resource agencies or divisions of NCDE Q, including NCDCM,
NCDMF, NCDWR, and NCWRC. Other corresponding agencies are the NCDOT and the NC Office of State
Archaeology (NCOSA).
A CZMA Consistency Concurrence is not required for the proposed project . See Section 10.6.
10.7 Wild and Scenic Rivers Act—National Wild & Scenic River System
The proposed project area is not located in a National Wild and Scenic River System or in or near a river
designated by Congress as a “study river” for possible inclusion.

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10.8 Effects on Federal Projects —Section 14 of Rivers & Harbors Ac t (33 USC 408)
As administered by the USACE, Section 14 of the Rivers and Harbors Act regulates construction, filling,
dredging, or excavation in navigable waters of the United States. The proposed project would require a
408 permit issued by the USACE. Following the review and approval of this EA, a 408 w ould be issued.
10.9 Corps Wetlands Policy (33 CFR 320.4(b)—Wetlands Impacts
The proposed project will not impact wetlands.

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11.0 SPECIAL CONDITIONS
Beach nourishment projects which are conduc ted when threatened or endangered species are present in
the Action Area generally involve permits with special conditions incorporated. The special conditions
include mitigation and monitorin g measures designed to protect species at risk and ensure that sediment
quality meets acceptable standards.
11.1 Conditions Required
Some special conditions w ould be required. Conditions required to protect the public interest, ensure
effects are not significant, and/or ensure compliance of the activity with any of the laws above are dis -
cussed previously in this EA, including:
 Mitigation to protect threatened and endangered species
 Measures taken to ensure public safety
11.2 Required Special Condition(s)
Anticipated monitoring and mitigation measures outlined in Appendix B‒Monitoring and Mitigation
Measures of this EA. The final special conditions will be incorporated into the permit s by USACE and NPS
with input from federal (eg – USFWS and NOAA –NMFS) and state (NC DEQ–DCM) agencies. These special
conditions will be based on a review of the permit application, supporting documents, and the present EA.

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12.0 FINDINGS AND DETERMI NATIONS
12.1 Section 176 (c) of the Clean Air Act General Conformity Rule Review
The proposed permit action has been analyzed for conformity applicability pursuant to regulations imple -
menting Section 176(c) of the Clean Air Act. It has been determined that the activities proposed under this
permit will not exceed de minimus levels of direct or indirect emissions of a criteria pollutant or its
precursors and are exempted by 40 CFR Part 93.153. Any later indirect emissions are generally not within
the USACE continuing program responsibility and generally cannot be practicably controlled by the
USACE.
The Air Quality Section of the NCDE Q has jurisdiction over air quality in Dare County (applicant). According
to the Washington (NC) district office, ambien t air quality in Dare County complies with the National
Ambient Air Quality Standards (NAAQS). In addition, Dare County is located in an area classified by the US
Environmental Protection Agency (EPA) as being in attainment for all six criteria air pollut ants.
Activities associated with dredging and beach nourishment produce localized, temporary increases in
pollutant levels associated with operation of heavy machinery , mainly through the combustion of diesel
fuel. The highest levels would occur at the dredge offshore and at the active work zone along the beach.
Pollutant concentration s are expected to diminish exponentially with distance from construction and
return to ambient levels in close proximity to the work areas. Upon completion of the work, n o additional
discharges or sustained impacts would be associated with the proposed project. Windy conditions along
the Outer Banks are expected to disperse pollutants rapidly from the area. Emissions are not expected to
be at a level that would contribut e measurably to greenhouse gases on a wider scale and are not expected
to produce conditions that would alter Dare County’s current EPA classification.
For these reasons , a conformity determination is not required for this permit action .
12.2 Presidential Executive Orders (EO)
12.2.1 Consultation with Indian Tribes, Alaska Natives, and Native Hawaiians (EO 13175)
This action has no substantial effect on one or more India n tribes, Alaskan, or Hawaiian n atives.
12.2.2 Floodplain Management (EO 11988)
All federal agencies are required by Executive Order 11988 (Floodplain Management) to evaluate the
likely impacts of their actions in floodplains. The objectives of the EO 11988 are to avoid, as much as
possible, the short- and long-term adverse impacts associated with occupancy, modification, or
destruction of floodplains and to avoid indirect support of development and new construction in such
areas where there is a practicable alternative. NPS Director’s Order #77–2 (Floodplain Management)
provides NPS procedures for complying with EO 11988.

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The barrier-island floodplains help to reduce the impact of hurricanes and other storms on the
shorelines that they shelter. These floodplains provide storm-water holding capacity, reducing runoff
that could otherwise flood developed areas. They also provide habitat for species adapted to the coastal
barrier island environment. Storm events such as hurricanes and nor’easters (winter storms along the
mid-Atlantic coast) and associated wave action and high precipitation are the prime sources of flooding
in the Seashore. Additionally, some areas are known to be susceptible to minor flooding without wave
involvement when large amounts of rainfall occur.
North Carolina’s barrier islands have historically been and continue to be affected by coastal forces and
flooding events. The barrier islands of the Seashore are predominantly flat and narrow and lie adjacent
to the shallow and wide Pamlico Sound. The widest part of the Seashore is near Cape Point about six
miles south of Avon , between the villages of Buxton and Frisco (Pendleton et al 2005). According to
Federal Emergency Management Agency (FEMA) Flood Insurance Rate Maps for Dare County
(www.darenc.com/planning/floodmaps. asp, accessed May 2015), most of the Seashore is w ithin the
100-year floodplain with the exception of some areas that are located at the Navy tower site on Bodie
Island and a larger area on Hatteras Island near Buxton Village, which are within the 500 -year floodplain
(shaded X Zone). The proposed project area itself lies completely within the 100 -year floodplain
(https://fris.nc.gov/fris/index.aspx?FIPS=055&ST=NC&user=General %20Public, accessed May 2021).
Generally, lands along the ocean beaches and adjacent to the sound (at wide points) are in flood zone
VE, which is the flood insurance rate zone that corresponds to 100-year coastal floodplains that have
additional hazards associated with storm waves, high water tables, and periodic flooding. Zone VE is
also referred to as the Coastal High Hazard Area. Lands within the 100-year floodplain and not directly
adjacent to the ocean or sound lie within the AE zone, which is subject to waves less than 3 feet high
(NCDCCPS 2008); only zone VE is found within the Proposed Action Area.
None of the alternatives presen ted by the Applicant would elevate the Action Area above the floodplain or
reduce the capacity and function of the affected floodplain. The proposed project can only occur within
the floodplain, but it would not reduce the amount of floodplain. It would li kely widen the recreational
beach and potentially increase the capacity and function of the shoreface floodplain. The proposed
project would not pose a risk to humans, a n investment risk, or impact floodplain processes a nd values.
The
2017–2018 Buxton project was deemed exempt from the need to prepare a Floodplain Statement of
Findings per NPS Director’s Order #77 –2 Floodplain Procedures Manual V. B Exemptions (NPS 2015 e).
Floodplain was not discussed in the Final EIS of NPS Sediment Management Framework (N PS 2021ab).
Therefore, the impact of floodplains for the Avon project is dismissed from further analysis.

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12.2.3 Environmental Justice (EO 12898)
The USACE has determined that the proposed project would not use methods or practices that discrimi-
nate based on race, color, or national origin , nor would it have a disproportionate effect on minority or
low-income communities. Executive Order 12898, General Actions to Address Environmental Justice in
Minority Populations and Low -Income Populations, requires all federal agencies to incorporate environ -
mental justice into their missions by identifying and addressing the disproportionately high and/or
adverse human health or environmental effects of their programs and policies on minorities and low -
income pop ulations and communities. According to the EPA, environmental justice is the ...fair treatment
and meaningful involvement of all people, regardless of race, color, national origin, or income, with respect
to the development, implementation, and enforcemen t of environmental laws, regulations and policies. Fair
treatment means that no group of people, including a racial, ethnic, or socio -economic group, should bear a
disproportionate share of the negative environmental consequences resulting from industrial , municipal, and
commercial operations or the execution of federal, state, local, and tribal programs and policies.
The goal of fair treatment is not to shift risks among populations, but to identify potentially disproportion -
ately high and adverse effects and identify alternatives that may mitigate these impacts. Environmental
Justice is dismissed from further analysis for the following reasons:
 The park staff and planning team solicited public participation as part of the planning
process and gave equal consideration to all input from persons regardless of age, race,
income status, or other socio economic or demographic factors
 Implementation of the proposed project would not result in any identifiable adverse
human health effects. Therefore, there would be no direct or indirect adverse impacts on
any minority or low-income population
 The impacts associated with the implementation of the proposed project would not
disproportionately affect any minority or low -income population or community
Implementation of the proposed project would not result in any identified effects that would be
specific to any minority or low-income community.
12.2.4 Invasive Species (EO 13112)
Because no invasive species are present in the proposed project area, it is expected that they would have
no impact on the proposed project.
12.2.5 Energy Supply (EO 13212) and Availability (EO 13302)
The proposed project is not one that will increase the production, transmission, conservation of energy,
or strengthen pipeli ne safety.
The Council on Environmental Quality (CEQ) guidelines for implementation of NEPA require an exami-
nation of energy requirements and conservation potential as a possible impact topic in environmental

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USACE–Wilmington District (NC) 238 Avon Village, Dare County (NC)
documents [40 CFR 1502.16(e)]. Dare County strives to incor porate and encourage the prin ciples of
sustainable design* and development into all facilities and operations. The recently re -built Jennette’s
Pier (2011) at Nags Head in Dare County (~45 miles north of the project area) is a prime example of the
County’s support for sustainable design and ecologically sensitive use. Essentially, sustainability is living
within the environment with the lea st impact on the environment.
*[The objectives of sustainability are to design structures to minimize adverse impac ts on natural and cultural values,
to reflect their environmental setting, to maintain and encourage biodiversity, to construct and retrofit facilities using
energy efficient materials and building techniques, to operate and maintain facilities to promote their sustainability,
and to illustrate and promote conservation principles and practices through sustainable design and ecologically
sensitive use.]
The proposed project could potentially result in reduced use of energy and conservation over the design
life of the project if it reduces the frequency of storm repairs needed. Each emergency repair of the infra-
structure requires the use of heavy equipment and the importation of construction materials from distant
sources. However, the proposed project w ould not result in noticeable changes to energy requirements
or the ability to conserve energy resources during normal, daily activities common to the project area.
12.3 Findings of No Significant Impact
Having reviewed the information provided by the applicant and all interested parties and an assessment
of the environmental impacts, I find that this permit action will not have a significant impact on the quality
of the human environment. Therefore, an environmental impact statement will not be required.
12.4 Compliance with the Section 404(b)(1) Guidelines
Having reviewed the informa tion above, I find that the applicant’s proposed project meets Sect ion
404(b)(1) Guidelines provided certain monitoring and environmental protection measures are
implemented to the extent practicable as recommended by USFWS and NMFS under their respective
Biological Opinions applicable to the project .
12.5 Public Interest Determination
Having reviewed and considered the information above, I find that the proposed proj ect is not contrary to
the public interest.

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SIGNATURES

PREPARED BY:

________________________ Date:
Project Manager

REVIEWED BY:

________________________ Date:
Enter name of appropriate level reviewer

APPROVED BY:

________________________ Date:
Enter name of appropriate level approver

Modify signature lines as needed to reflect district’s signature delegation for standard permits

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