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ROY COOPER NORTH CAROLINA
Governor Environmental Quality
MICHAEL S. REGAN
Secretary
BRAXTON C. DAVIS
Director December 18, 2020
Mr. Johnny Martin
Moffatt & Nichol
4700 Falls of Neuse Road, Suite 300
Raleigh, NC 27609
Dear Mr. Martin:
The Division of Coastal Management hereby acknowledges receipt of your application, acting as agent for the
Town of Oak Island, for State approval to expand the Town of Oak Island's beach nourishment project, with
the expanded location extending from McGlamery St to SE 63rd St. and between 7th/1 Oth PL W to the West
End Beach Access, in Oak Island, Brunswick County, and adjacent to the Atlantic Ocean. It was received as
complete on 11/25/20 and appears to be adequate for processing at this time. The projected deadline for
making a decision is 2/8/21. An additional 75-day review period is provided by law when such time is
necessary to complete the review. If you have not been notified of a final action by the initial deadline stated
above, you should consider the review period extended. Under those circumstances, this letter will serve as
your notice of an extended review. However, an additional letter will be provided on or about the 75th day.
If this agency does not render a permit decision within 70 days from 11/25/20 you may request a meeting with
the Director of the Division of Coastal Management and permit staff to discuss the status of your project. Such
a meeting will be held within five working days from the receipt of your written request and shall include the
applicant and project designer/consultant.
NCGS I I3A-119(b) requires that Notice of an application be posted at the location of the proposed
development. Enclosed you will find a "Notice of Permit Filing" postcard which must be posted at the property
of your proposed development. You should post copies of this notice at a conspicuous point along the project
area where it can be observed by the public. Failure to post this notice could result in an incomplete
application.
An onsite inspection will be made, and if additional information is required, you will be contacted by the
appropriate State or Federal agency. Please contact me if you have any questions and notify me in writing if
you wish to receive a copy of my field report and/or comments from reviewing agencies.
Sincerely,
Heather
Beach & Inlet Management Project Coordinator
cc: MHC Files, DCM David Kelly, Town of Oak Island
Greg Currey, COE Dawn York, Moffatt & Nichol
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North Carolina Department of Environmental Quality j Division of Coastal Management
Wilmington Office 127 Cardinal Drive Extension Wilmington, North Carolina 28405
910.796.7215

DIVISION OF COASTAL MANAGEMENT
FIELD INVESTIGATION REPORT
APPLICANT'S NAME: Town of Oak Island- Major Modification of Permit No. 31-20
2. LOCATION OF PROJECT SITE: The project site is located on Oak Island, from McGlamery St to SE
63rd St and from between 7'h & 1 Oth PL W to the West End Beach Access, Brunswick County.
Approximate State Plane Coordinates — Approx. Lat: 33.902890' N (start)/ 33.912873' N (end)
Long: 78.074842' W (start) / 78.227846' W (end)
3. INVESTIGATION TYPE: CAMA / D&F
4. INVESTIGATIVE PROCEDURE: Dates of Site Visit — 8/26/20,
Was Applicant Present — No
5. PROCESSING PROCEDURE: Application Received—11/25/20
Office — Wilmington
6. SITE DESCRIPTION:
(A) Local Land Use Plan — Town of Oak Island
(B) AEC(s) Involved: OH, PTA
(C) Water Dependent: Yes
(D) Intended Use: Public
(E) Wastewater Treatment: Existing — Municipal Sewer
Planned - N/A
(F) Type of Structures: Existing — Primarily residential structures and accessways
Planned — Dune construction and beach renourishment project
(G) Estimated Annual Rate of Erosion: 0'-2'/year SBF: 2'/year
7. HABITAT DESCRIPTION:
(R)
[AREA]
DREDGED FILLED OTHER
(A) Vegetated Wetlands (coastal)
(B) Other (Below MHW)
— 484 acres
— 134 acres
(C) Other (Above MHW)
—63 acres
Total Area Disturbed: —I97 acres of beach fill
Primary Nursery Area: No
(I) Water Classification: SB Open: No
8. PROJECT SUMMARY: The applicant is proposing to expand their beach nourishment project to
include McGlamery St to SE 63rd St and between 7th/1 Oth PL W to the West End Beach Access.
North Carolina Department of Environmental Quality I Division of Coastal Management
Wilmington Office 127 Cardinal Drive Extension 1 Wilmington, North Carolina 28405
910.796.7215

Town of Oak Island Beach Nourishment- Major Modification P31-20
Page Two
9. PROJECT DESCRIPTION:
The Town of Oak Island is located on a south facing barrier island in Brunswick County between
Lockwoods Folly Inlet and the Town of Holden Beach to the west, and the Town of Caswell Beach and
the Cape Fear River to the east. The Town of Caswell Beach is also located on the island. The Town of
Oak Island is approximately 9 miles in length. It is also bordered by the Atlantic Intracoastal Waterway
(AIWW) to the north and the Atlantic Ocean to the south. The island is accessed via 2 bridges. The
western bridge leads into the Town of Oak Island located off NC Highway 211 via Middleton Blvd. The
eastern bridge leads onto the island between Oak Island and Caswell Beach and is accessed from NC
Highway 133.
This is a proposed modification to the Town's State CAMA/Dredge & Fill Permit No. 31-20 which was
issued in early 2020 (USACE AID# SAW-2018-02230 and DWR Project 92018-1344). A minor
modification was issued shortly thereafter to potentially authorize the removal of a buffer in the borrow
area, should a reported magnetic anomaly be identified as marine debris and removed from the borrow
site. The proposed project would extend the previously permitted project to include the entire oceanfront
shoreline of the Town of Oak Island. The long-term erosion rate for the proposed project area ranges from
0'-2.6'/year. The Division's calculated 100-year storm recession line for the island was predicted to be
180'. Oak Island has experienced significant beach erosion within the last several years as a result of the
numerous recent tropical storms and hurricanes that have affected our coast.
In the original application, the permittee identified a --304 acre borrow site off Jay Bird Shoals to supply
sand for the project. Water depths at the site varied from approximately -20 to -28' NAVD88. Sediments
collected via Vibracore samples within the borrow site showed a Unified Soils Classification System
(USCS) designation of predominantly SP-SM or SW. Gravel sized material (>4.76mm) ranged from 0-
7% with a maximum composite weight of 4.25%. Fines (<0.0625 mm) in individual samples ranged from
1.29% to 9.87% with a maximum composite weight of 6.79% overall. A low -intensity, long -duration
linear feature was originally identified within the borrow site by a remote sensing survey and a minimum
50' buffer area on each side of the anomaly is proposed (see Appendix D- Archeological Remote Sensing
for more information). A follow-up Phase II Remote -Sensing Archeological Survey was later submitted
for inclusion in the application package and a request to remove the buffer was later submitted as a minor
modification request as the anomaly is believed to be modern debris. Dredge depths were divided into
three zones: Zone 1 with an excavation depth of -26' NAVD88, Zone 2 with an excavation depth of -31'
NAVD88, and Zone 3's permitted dredge depth was -27' NAVD88.
The previously permitted placement area extended from 10t1i Place West to SE 63`d Street (-21,000 feet).
The beach fill template included berm fill to an elevation of+7' NAVD 88 with a 20: 1 slope out to tie
into existing grade from - I' to -10' NAVD88 and a dune at an elevation ranging from 13.5' to 14.5'
NAVD88, constructed with a 6' wide dune crest, and at a 5:1 slope. Excavation was calculated at 1.1
million cubic yards with an anticipated final net fill volume of approximately 846,000 cubic yards due to
expected dredge losses.
The native beach was characterized using data collected by Athena. Fines were calculated at 1.88%, with
sand comprising 98.96%, and granular and gravel material each at less than 1%. Mean grain size was
calculated at 0.27mm. Calcium carbonate was reported at 9.72%. The count of shell and
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North Carolina Department of Environmental Quality Division of Coastal Management
Wilmington Office 127 Cardinal Drive Extension I Wilmington, North Carolina 28405
910.796,7215

Town of Oak Island Beach Nourishment- Major Modification #31-20
Page Three
rock material greater than 3" in size was determined to number 58 within a 50,000 square foot area, as
previously determined during the original permit application.
Since the original beach nourishment project was permitted, Hurricane Isaias resulted in significant
erosion of the beach. In response, the Town's major permit for beach bulldozing was modified to allow
them to bulldoze the damaged dune system. This work has been completed. The Town is also repairing
dunes by replacing storm -overwashed sand lost from the beach and dune system via truck haul. This latter
work is exempt from CAMA permitting requirements as it is defined in the Coastal Resources
Commission (CRC) roles as maintenance and repair. This work is being conducted at the present time.
The waters in the project area fall within the Lumber and Cape Fear River Basins, as classified by the NC
Division of Water Resources (DWR). The waters of the Atlantic Ocean are classified as SB by the DWR.
The NC Division of Marine Fisheries has NOT designated any of the areas to be impacted as a Primary
Nursery Area, and there are no foreseen impacts to shellfish resources at this time.
PROPOSED PROJECT:
The applicant is proposing to expand the limits of the previously permitted beach nourishment and dune
building project for the Town of Oak Island. The project site extends the distance of the previously
permitted project approximately 26,100 additional linear feet in total, with 2 reaches extending from
McGlamery St to SE 63rd St, and a second reach starting between 7" & 1 Oth PL W and extending to the
West End Beach Access. The beach berm would be filled to an elevation of+7' NAVD 88 with a 20: 1
slope out to tie into existing grade from -1' to -9' NAVD88 (MLW= -2.9' NAVD88). An engineered
"starter dune" is also proposed along the majority of the expanded area with a maximum elevation
ranging from +13.0' to +15.5' NAVD88, to be constructed with a 10' wide dune crest, and with a 4:1
slope on the waterward side and a 5:1 slope on the landward side. This design appears to advance the
proposed engineered dune to (or in one area waterward of) the current MHW line along part of the project
area. Anticipated fill volumes for the project would place a minimum of 15 with an average of 50 cubic
yards per linear foot. As proposed, a gross excavated volume of up to 1.667 million Cubic yards of sand
has been calculated to account for an estimated placement loss of up to 30%. A total fill volume of
approximately 1,282,000 cubic yards is anticipated to be placed on the beach, given current conditions. It
is currently estimated that 5,852,607 square feet would be filled below MHW (535,834 cubic yards). Of
that material, approximately 2,150,482 square feet (191,049 cubic yards) would also be located below
MEW. Approximately 2,740,996 square feet (746,166 cubic yards) of beach fill material would be placed
above the MHW line. The applicant also estimates approximately 93' of fill would be placed water -ward
of the current MHW line on average, within a maximum projected distance of 279' of fill placed below
MHW. A table provided by the applicant in the narrative (Table 2-3) shows the average pre -Matthew
beach width ranging from 57'-69', and the average anticipated post -construction equilibrated beach width
ranging from 73'-96'. However, it should be noted that the estimates provided are based on a single
"representative profile" for each area (4 profiles in total for the project area) and estimated equilibration
was simulated using SBEACH and a 2-year return period storm. While the applicant asserts the estimated
equilibrated recreational beach width (the distance between +7' NAVD88 to MHW) will increase the
beach width that existed prior to Hurricane Matthew, there appears to be potential for post -equilibration
narrowing of the beach width should Oak Island experience more than a 2-year storm.. The applicant has
also stated this project is the second phase of the Town's overall plan, and the Town still intends to apply
for a more comprehensive beach restoration project in the near future, but there is no apparent
North Carolina Department of Environmental Quality Division of Coastal Management
Wilmington Office 127 Cardinal Drive Extension I Wilmington, North Carolina 28405
910.7967215

Town of Oak Island Beach Nourishment- Major Modification #31-20
Page Four
guarantee of future projects at this time; as stated in the narrative, future projects are dependent on
funding. The application states the purpose of the project, which is designed to withstand a 25-year return
period storm event, is to protect infrastructure and property while maintaining tax revenues to the Town,
County and State, as well as to preserve the environmental, cultural, and aquatic resources of the Town
and County. Planting of dune vegetation is also proposed on the crest and backslope of the proposed
started dune. This would likely facilitate the establishment of stable, natural vegetation. And while the
applicant states the importance of maintaining the pre -Matthew dune and location of stable, natural
vegetation to protect construction setbacks, the project design shifts the starter dune waterward of the
frontal dune's pre -Matthew location, as shown in the profile drawings included in Appendix J-
Supplemental Profiles and Figures 2-8 and 2-9 of the narrative (Project Stations 667+65 & 669+65).
The applicant states the entire volume of material will still be available in the previously permitted Jay
Bird Shoals site, as proposed, although they are also requesting to allow dredging from a second borrow
area at Central Reach, The Jay Bird Shoals site has been divided into three zones: Zone 1 would be
excavated to a depth of -26' NAVD88, with a proposed 2' dredge overdepth allowance proposed for the
entire borrow area. Therefore, maximum proposed dredge depth for Zone 1 would be -28' NAVD88.
Zone 2 would be excavated to a design depth of -35' (+2') NAVD88 and Zone 3's proposed dredge depth
is -27' (+2') NAVD88. This is a change from the originally permitted dredge depths to account for
overdredge allowance not included in the original application for Zones 1 and 3 and dredge additional
depth in Zone 2. The sediment analysis has been updated for the site to account for the additional dredge
depth. The mean grain size for the Jay Bird Shoals borrow area, as reported based on a revised composite
of applicable vibracore samples within the newly proposed dredged depths, is 0.27mm. Gravel is reported
at 1.27%, granular material at 3.57%, fines at 4.61%, and calcium carbonate is now reported at 13.98%.
The applicant estimates the volume of material available in the Jay Bird Shoals site, after accounting for
material dredged during the upcoming 2020/21 project and the dredge buffers, is approximately 2.59
million cubic yards.
Updated wave & sediment transport modeling has also been reported for the modified template due to
concerns previously expressed by the Village of Bald Head Island and Town of Caswell Beach. The
updated modeling report can be found in Appendix D and a brief discussion of the results can be found in
Section 2.4 of the narrative (p. 45-47). Monitoring of the Caswell Beach shoreline would continue
annually for 3 years post -construction, in accordance with their previous commitment in the original
permit application, as stated on page 53 of the narrative and in Appendix G.
The proposed 180-acre Central Reach borrow area, located approximately 1.9 miles offshore of the Oak
Island shoreline, is reported to contain 1.18 million cubic yards of beach -compatible material. Up to
615,000 Cubic yards of material is proposed to be excavated at the targeted depths. The proposed Central
Reach borrow area partially overlaps the borrow area authorized for the Town of Holden Beach (State
Permit 414-02, SAW 2012-00286 and DWR Project 42001-1836, see Figure 2-2 in the narrative for both
borrow area locations). The Town of Oak Island's proposed Central Reach borrow area is divided into 4
zones of varying depth, all with a proposed +2' overdredge allowance. Zone 1 would target a dredge
depth of -38' NAVD 88 (+2'), Zone 2 would target a depth of 39.7' (+2') NAVD 88, and Zones 3 and 4
would target dredge depths of-37.3' (+2') and -40' (+2') NAVD 88, respectively. Vibracores taken from
the proposed Central Reach borrow area show a mean grain size of 0.32mm with an average composite
sand content of 86.53%. The average composite gravel content for material within proposed dredge
depths in this borrow area is 3.4%, the average granular content of 4.97%, average fines content is 5.09%
and average calcium carbonate is 16.17%. Sediment color in the borrow area was predominantly 10YR
3/1 when the vibracores were first analyzed and samples were later reassessed after a period of exposure
North Carolina Department of Environmental Quality Division of Coastal Management
Wilmington Office 127 Cardinal Drive Extension I Wilmington. North Carolina 28405
910196.7215

to the stun to estimate potential for bleaching (see pages 42-44 of the narrative and Appendix B2 for the
Central Reach vibracore logs). All samples within proposed dredge depths were reported at a Munsell
value of 10YR 5/1 or 6/1 while dry after time, but when reevaluated while wet, several samples still
remain the original darker 10YR 3/ 1 value (see page I of Appendix 132). No cultural resources were
identified in an Archeological Assessment performed in 2019 by Tidewater Atlantic Research, Inc. (see
Appendix E).
Dredging would be conducted either via a hopper dredge, with sediment transported to offshore
temporary mooring, then pumped by submerged pipeline onto the beach, or excavated via cutterhead
dredge and piped directly to the beach from the borrow area.
10. ANTICIPATED IMPACTS
The proposed dredging associated with the project would result in impacts to up to 484 acres of
submerged bottom state waters. Up to 304 acres would be dredged at Jay Bird Shoals and the proposed
Central Reach borrow area covers 180 acres. The project would result in the fill of approximately 63 acres
of upper beach (above MHW) and would fill approximately 134 acres of intertidal area and nearshore
shallow bottom. The dredging and beach fill would result in temporary increases in turbidity. Temporary
impacts to benthic and invertebrate infaunal communities can be expected. The applicant is proposing to
limit all dredging, sand placement and associated construction activities to the environmental window
between November 16 through April 30, thereby avoiding peak periods of biological activity. The
applicant has also committed to monitoring sand placement throughout the project to ensure material is
compatible and complies with State Technical Standards (15A NCAA07H .0312) through daily
inspections and weekly sediment analysis reports, as well as committing to utilizing existing permanent
beach accessways with heavy equipment and via existing public access corridors. The narrative states
they would locate staging areas for construction equipment off the beach in areas identified on the plans
(See Figure 2-17), but daily equipment staging would be located on the beach seaward of the dune line.
The narrative also states the applicant agrees to abide by many of the standard conditions as addressed in
Section 4 of the Narrative (Proposed Conservation Measures) and as included in the 2020 South Atlantic
Regional Biological Opinion (SARBO 2020).
Submitted by: Heather Coats Date: December 17, 2020 Office: Wilmington
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North Carolina Department of Environmental Quality i, Division of Coastal Management
Wilmington Office 127 Cardinal Drive Extension Wilmington, North Carolina 28405
910,796.7215