HomeMy WebLinkAbout20140338 Ver 1_Final Mitigation Plan 8-3-15_20150825
Mitigation Plan
FINAL
JULY 31, 2015
Maney Farm Mitigation Project
Chatham County, NC
DENR Contract No. 005793
DMS ID No. 96314
Cape Fear River Basin
HUC 03030002
PREPARED BY:
312 West Millbrook Road
Suite 225
Raleigh, NC 27609
PREPARED FOR:
NC Department of Environment and Natural Resources
Division of Mitigation Services
1652 Mail Service Center
Raleigh, NC 27699-1652
FINAL MITIGATION PLAN
Maney Farm Mitigation Project
Chatham County, NC
DENR Contract No. 005793
DMS ID No. 96314
Cape Fear River Basin
HUC 03030002
PREPARED FOR:
NC Department of Environment and Natural Resources
Division of Mitigation Services
1652 Mail Service Center
Raleigh, NC 27699-1652
PREPARED BY:
Wildlands Engineering, Inc.
312 W Millbrook Rd, Suite 225
Raleigh, NC 27609
Phone: 919-851-9986
JULY 31, 2015
Maney Farm Mitigation Project
Final Mitigation Plan Page ii
EXECUTIVE SUMMARY
Wildlands Engineering, Inc. is completing a full delivery project at the Many Farm Mitigation Site (Site) in
Chatham County, North Carolina. The stream restoration and enhancement project is sponsored by the
North Carolina Division of Mitigation Services (DMS) and will improve a total of 6,092 linear feet of
perennial and intermittent stream and generate 4,922 stream mitigation units. The streams proposed
for restoration and enhancement are all unnamed tributaries (UT) to South Fork Cane Creek (SF) and are
referred to herein as UTSF, UT1, UT2, UT3, UT4, and UT5. This site is located in the Cape Fear River Basin
8-Digit Hydrologic Unit Code (HUC) 03030002. The Site is also within the Cane Creek Targeted Local
Watershed (HUC 03030002050050), which flows into Cane Creek and eventually into the Haw River.
The proposed Site is located within the Cane Creek Targeted Local Watershed (TLW) which is discussed
in NCDMS’s 2009 Cape Fear River Basin Restoration Priorities (RBRP). This document identifies the need
to improve aquatic conditions and habitats as well as promoting good riparian conditions in the Cane
Creek watershed and notes that there are currently 51 active animal operations in the watershed. The
Maney Farm Site is currently maintained as cattle pasture and is one of the 51 animal operations
referenced in the RBRP.
The Site drains to the Haw River, which flows to B. Everett Jordan Lake (Jordan Lake). The 2005 NCDWR
Cape Fear River Basinwide Water Quality Plan indicates that Jordan Lake is a drinking water supply (WS-
IV), a primary area for recreation, and a designated Nutrient Sensitive Water which calls for reduction of
non-point source pollution. The water supply watershed boundary for Jordan Lake is just six miles
downstream from the Site. The Cape Fear watershed is also discussed in the 2005 North Carolina
Wildlife Resource Commission’s Wildlife Action Plan where sedimentation is noted as a major issue in
the basin. Maps within the Wildlife Action Plan indicate that Priority Species are present along Cane
Creek. Restoration at the Site will directly address non‐point source stressors by removing cattle from
the streams, creating stable stream banks, restoring a riparian corridor, and placing approximately 16.7
acres of land under permanent conservation easement.
The proposed project will help meet the goals for the watershed and provide numerous ecological
benefits within the Cape Fear River Basin. While many of these benefits are limited to the project area,
others, such as pollutant removal, reduced sediment loading, and improved aquatic and terrestrial
habitat, have farther-reaching effects. In addition, protected parcels downstream of this site promote
cumulative project benefits within the watershed.
This mitigation plan has been written in conformance with the requirements of the following documents
that govern NCDMS operations and procedures for the delivery of compensatory mitigation.
Federal rule for compensatory mitigation project sites as described in the Federal Register Title
33 Navigation and Navigable Waters Volume 3 Chapter 2 Section § 332.8 paragraphs (c)(2)
through (c)(14).
DMS In-Lieu Fee Instrument signed and dated July 28, 2010.
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TABLE OF CONTENTS
EXECUTIVE SUMMARY ....................................................................................................................... ii
Table of contents .............................................................................................................................. iii
1.0 Restoration Project Goals and Objectives ............................................................................1
2.0 Project Site Location and Selection ......................................................................................2
2.1 Directions to Project Site ........................................................................................................... 2
2.2 Site Selection and Project Components .................................................................................... 3
3.0 Site Protection Instrument ..................................................................................................3
4.0 Baseline Information –Project Site and Watershed Summary ...............................................3
4.1 Watershed Existing Conditions ................................................................................................. 3
4.2 Watershed Historical Land Use and Development Trends ....................................................... 3
4.3 Physiography, Geology, and Soils .............................................................................................. 5
4.4 Valley Classification ................................................................................................................... 6
4.5 Surface Water Classification and Water Quality ....................................................................... 6
4.6 Existing Stream Condition ......................................................................................................... 6
4.7 Channel Evolution ................................................................................................................... 12
4.8 Channel Stability ...................................................................................................................... 13
4.9 Utilities and Site Access ........................................................................................................... 14
5.0 Regulatory Considerations ................................................................................................ 14
5.1 401/404 ................................................................................................................................... 14
5.2 Threatened and Endangered Species ...................................................................................... 19
5.3 Cultural Resources ................................................................................................................... 20
5.4 FEMA Floodplain Compliance and Hydrologic Trespass ......................................................... 21
6.0 Reference Sites ................................................................................................................. 21
6.1 Reference Streams .................................................................................................................. 21
6.2 Channel Morphology and Classification of Reference Streams .............................................. 21
7.0 Determination of Credits ................................................................................................... 25
8.0 Credit Release Schedule .................................................................................................... 26
8.1 Initial Allocation of Released Credits ....................................................................................... 26
8.2 Subsequent Credit Releases .................................................................................................... 27
9.0 Project Site Mitigation Plan ............................................................................................... 27
9.1 Justification for Proposed Intervention ................................................................................... 27
9.2 Stream Restoration and Enhancement Design Overview ....................................................... 27
9.3 Design Discharge Analysis ....................................................................................................... 27
Note: Units for all discharge estimates are cubic feet per second. ........................................................ 29
9.4 Design Channel Morphologic Parameters ............................................................................... 29
9.5 Sediment Transport Analysis ................................................................................................... 32
9.6 Project Implementation .......................................................................................................... 34
10.0 Maintenance Plan ............................................................................................................. 37
11.0 Performance Standards ..................................................................................................... 37
11.1 Streams .................................................................................................................................... 37
12.0 Monitoring Plan ................................................................................................................ 39
12.1 Streams .................................................................................................................................... 39
13.0 Long-Term Management Plan ........................................................................................... 42
14.0 Adaptive Management Plan .............................................................................................. 42
15.0 Financial Assurances ......................................................................................................... 42
16.0 References ........................................................................................................................ 44
Maney Farm Mitigation Project
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TABLES
Table 1: Mitigation Goals and Objectives ............................................................................................2
Table 2: Site Protection Instrument ....................................................................................................3
Table 3: Project and Watershed Information.......................................................................................4
Table 4: Project Soil Types and Descriptions........................................................................................5
Table 5: Reach Summary Information .................................................................................................9
Table 6: Stream Existing Conditions .................................................................................................. 10
Table 7: Existing Conditions Channel Stability Assessment Results ..................................................... 14
Table 8: Wetland Summary Information ........................................................................................... 16
Table 9: Listed Threatened and Endangered Species in Chatham County, NC ..................................... 19
Table 10: Summary of Reference Reach Geomorphic Parameters ...................................................... 23
Table 11: Determination of Credits ................................................................................................... 25
Table 12: Credit Release Schedule – Stream Credits .......................................................................... 26
Table 14: Design Morphological Parameters ..................................................................................... 30
Table 15: Sediment Transport Competence Analysis ......................................................................... 33
Table 16: Planting List ...................................................................................................................... 36
Table 17: Maintenance Plan ............................................................................................................. 37
FIGURES
Figure 1 Vicinity Map
Figure 2 Site Map
Figure 3 Watershed Map
Figure 4 Soils Map
Figure 5 USGS Map
Figure 6 Hydrologic Features Map
Figure 7 FEMA Flood Map
Figure 8 Reference Reach Vicinity Map
Figure 9 Concept Design Map
Figure 10 NC Piedmont Regional Curves with Project Data Overlay
Figure 11 Proposed Monitoring Components Map
APPENDICES
Appendix 1 Site Photographs
Appendix 2 Site Protection Instrument and Plat
Appendix 3 Historic Aerial Photographs
Appendix 4 NCDWR Stream Classification Forms
Appendix 5 Existing Geomorphic Survey Data
Appendix 6 HEC-20 Channel Stability Assessment Data
Appendix 7 USACE Routine Wetland Determination Data Forms, NCWAM Data Forms, and
Jurisdictional Determination
Appendix 8 Pre-construction Notification
Appendix 9 Categorical Exclusion
Appendix 10 Floodplain Development Permit Correspondence
Maney Farm Mitigation Project
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1.0 RESTORATION PROJECT GOALS AND OBJECTIVES
The Maney Farm Mitigation Site (referred to herein as Site or Project) is located in the Cane Creek
Watershed which has been designated a Nutrient Sensitive Water (NSW). The project streams flow
into South Fork Cane Creek which flows into Cane Creek. Cane Creek flows to the Haw River and
eventually into the B. Everett Jordan Lake (Jordan Lake). The Site’s watershed is within 14-Digit
Hydrologic Unit Code (HUC) 03030002050050 which was identified as a Cape Fear 02 Targeted
Local Watershed (TLW) in the NC Division of Mitigation Services’ (DMS) 2009 Cape Fear River Basin
Restoration Priority (RBRP) plan. The parcel immediately downstream of the Site is currently under
both a Farmland Preservation Trust Fund Easement and a Piedmont Land Conservancy Easement.
The restored stream reach and riparian corridor will further extend the protected wildlife habitat
within these two parcels. DMS also maintains easements on adjacent parcels (i.e., the Hadley
Newlin site) promoting cumulative project benefits within the watershed.
The proposed Site is located within the Cane Creek TLW and is discussed in DMS’s 2009 Cape Fear
RBRP plan. This document identifies the need to improve aquatic conditions and habitats as well as
promoting good riparian conditions in the Cane Creek watershed and notes that there are currently
51 active animal operations in the watershed. The Site is currently maintained as cattle pasture and
is one of the 51 animal operations referenced in the RBRP plan.
The 2005 NC Division of Water Resources (NCDWR) Cape Fear River Basinwide Water Quality Plan
indicates that Jordan Lake is a drinking water supply, a primary area for recreation, and a
designated NSW which calls for reduction of non-point source pollution. The water supply
watershed boundary for Jordan Lake is just six miles downstream from the Site. The Cape Fear
watershed is also discussed in the 2005 North Carolina Wildlife Resource Commission’s Wildlife
Action Plan where sedimentation is noted as a major issue in the basin. Maps within the Wildlife
Action Plan indicate that Priority Species are present along Cane Creek. Restoration at the Site will
directly address non‐point source stressors by removing cattle from the streams, creating stable
stream banks, restoring a riparian corridor, and placing approximately 16.7 acres of land under
permanent conservation easement.
The Project will help meet the functional goals described in the Cape Fear RBRP plan through
stream restoration and enhancement activities and riparian buffer re-establishment. Project goals
are desired project outcomes and are verifiable through visual assessment and/or measurement.
Objectives are activities that will result in the accomplishment of goals. The project will be
monitored after construction to demonstrate success as described in Section 12. The project goals
and related objectives are described in Table 1.
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Table 1: Mitigation Goals and Objectives
Maney Farm Mitigation Project
Goal Objective Expected Outcomes
Exclude cattle from project
streams
Install fencing around conservation
easements adjacent to cattle pastures
Reduce pollutant inputs including
fecal coliform, nitrogen, and
phosphorous.
Stabilize eroding stream
banks
Reconstruct stream channels with stable
dimensions. Add bank revetments and
in-stream structures to protect
restored/enhanced streams.
Reduce inputs of sediment into
streams.
Construct stream channels
with that are laterally and
vertical stable
Construct stream channels that will
maintain a stable pattern and profile
considering the hydrologic and
sediment inputs to the system, the
landscape setting, and the watershed
conditions.
Return a network of streams to a
stable form that is capable of
supporting hydrologic, biologic,
and water quality functions.
Improve instream habitat
Install habitat features such as
constructed riffles and brush toes into
restored/enhanced streams. Add woody
materials to channel beds. Construct
pools of varying depth.
Improve aquatic communities in
project streams.
Reconnect channels with
floodplains so that
floodplains are inundated
relatively frequently
Reconstructing stream channels with
appropriate bankfull dimensions and
depth relative to the existing floodplain.
Raise local groundwater
elevations. Inundate floodplain
wetlands and vernal pools.
Reduce shear stress on channels
during larger flow events.
Restore and enhance native
floodplain forest
Plant native tree and understory species
in riparian zone
Create and improve forested
riparian habitats. Provide a
canopy to shade streams and
reduce thermal loadings. Create a
source of woody inputs for
streams. Reduce flood flow
velocities on floodplain and allow
pollutants and sediment to settle.
Permanently protect the
project site from harmful
uses.
Establish a conservation easement on
the site.
Ensure that development and
agricultural uses that would
damage the site or reduce the
benefits of project are prevented.
2.0 PROJECT SITE LOCATION AND SELECTION
2.1 Directions to Project Site
The Site is located in northwestern Chatham County (35.838333, -79.343889), northwest of
Pittsboro and north of Silk Hope (Figure 1).
From Raleigh, NC, take I-40 West towards Durham. Take exit 293A for US-1 / US-64 / West toward
Sanford/Asheboro. Travel approximately three miles and take exit 98B for US-64 West. Travel
approximately 25 miles, take exit 381 for NC-87 towards Burlington. Travel approximately 1.8 miles
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on NC-87 North and turn left onto Silk Hope Gum Springs Road. Continue for 8.1 miles to Silk Hope
Lindley Mill Road. Take Silk Hope-Lindley Mill Road north 3.6 miles. Turn right on Center Church
Road and travel 0.9 miles. The Site is located north of Center Church Road.
2.2 Site Selection and Project Components
The Site has been selected by the DMS to provide stream mitigation units (SMUs) in the Cape Fear
River Basin. It was selected based on the current degraded condition of the on-site streams and the
potential for functional restoration and ecological uplift.
The project includes a combination of stream restoration and enhancement. The streams proposed
for restoration and enhancement are all unnamed tributaries (UT) to South Fork Cane Creek and
are referred to herein as UTSF, UT1, UT2, UT3, UT4, and UT5 (Figure 2). Jurisdictional wetlands are
present in the surrounding floodplain that will be enhanced as part of the project but are not
proposed for credit at this time. Photographs of the Site are included in Appendix 1.
3.0 SITE PROTECTION INSTRUMENT
The land required for construction, management, and stewardship of this mitigation project
includes portions of the parcel listed in Table 2. A conservation easement will be recorded on the
parcel to include the streams being restored and enhanced along with their corresponding riparian
buffers. A copy of the site protection instrument and recorded plat are included in Appendix 2.
Table 2: Site Protection Instrument
Maney Farm Mitigation Project
Landowner PIN County Site Protection
Instrument
Deed Book
and Page
Number
Acreage to be
Protected
M Darryl Lindley Rev
Trustee
8795-99-2158 Chatham Conservation
Easement
TBD 16.694
All site protection instruments require 60-day advance notification to the Corps and the State prior
to any action to void, amend, or modify the document. No such action shall take place unless
approved by the State.
4.0 BASELINE INFORMATION –PROJECT SITE AND WATERSHED SUMMARY
4.1 Watershed Existing Conditions
Table 3 presents the project information and baseline watershed information. The watershed areas
were delineated using a combination of-site existing conditions survey, Chatham County, NC GIS
data and USGS 7.5-minute topographic quadrangles (Figure 3).
4.2 Watershed Historical Land Use and Development Trends
The UTSF watershed (Figure 3) is located in the rural countryside approximately four miles north of
Silk Hope, NC. Topography can be described as somewhat hilly to gently rolling. The stream valleys
within the watershed and on-site are characterized by relatively narrow floodplains and
moderately steep side slopes.
A review of historical aerials of the Site and immediately adjacent parcels from 1973, 1983, and
1993 (Appendix 3) revealed that the Site has been used for hay production and/or agricultural
livestock production since before 1973. The limits of riparian buffer and agricultural land have
Maney Farm Mitigation Project
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remained consistent over that time. Further investigation was done on landuse throughout the
entire watershed using the aerial photographs listed above and additional aerials from Google
Earth™ (1972-2014). The most common historical and current land use types are agricultural
livestock production and grazing, silviculture, and agricultural cropland.
Table 3: Project and Watershed Information
Maney Farm Mitigation Project
Project
County Chatham
Easement
Area (acres) 16.4
Project
Coordinates
35°50'18.00"N, 79°20'38.00"W
(35.838333, -79.343889)
Physiographic
Region Carolina Slate Belt of the Piedmont Physiographic Province
Ecoregion Piedmont
River Basin Cape Fear
USGS HUC (8
digit, 14 digit) 03030002, 03030002050050
NCDWR Sub-
basin 03-06-04
Reaches UTSF-R1 UTSF-R2 UT1A UT1B UT1C UT2A/B UT3A/B UT4A/B UT5
Drainage
(Area (acres) 115 211 16 4 19 11 10 20 76
Drainage Area
(miles2) 0.18 0.33 0.02 0.01 0.03 0.02 0.02 0.03 0.12
NCCGIA Land Cover Classification (%)
Hay / Pasture 72 67 74 56 57 67 95 53 64
Deciduous
Forest 25 23 26 0 29 33 1 35 28
Mixed Forest 0 3 0 0 0 0 4 7 2
Developed 0 3 0 44 13 0 0 0 0
Cultivated
Crops 3 2 0 0 0 0 0 0 4
Scrub / Shrub 0 1 0 0 0 0 0 0 2
Herbaceous 0 1 0 0 1 0 0 5 0
Wildlands conducted a watershed reconnaissance visit to verify current land uses observed in aerial
photography and to identify potential watershed stressors that could impact streams on-site. Land
use in the UTSF watershed was found to be consistent with information depicted in aerial
photography. Disturbed areas within the watershed consist primarily of agricultural landuses. As
this is a long-term, on-going practice (dating to before 1973) it is not considered a new stressor to
the watershed. There are no evident signs of impending land use changes or development pressure
that would impact the project in the UTSF watershed. The drainage upstream of the project site
consists of a network in small ditches which have been maintained in the current locations and
alignments since at least 1973. Sediment supply from the upstream watershed is small and likely to
remain stable. The Conservation Easement to be placed around the Site will eliminate potential for
future development or agricultural use in the immediate vicinity of the on-site streams.
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4.3 Physiography, Geology, and Soils
The project is located in the Slate Belt of the Piedmont Physiographic Province. The Piedmont
Province is characterized by gently rolling, well rounded hills with long low ridges, with elevations
ranging from 300 – 1,500 feet above sea level. The Carolina Slate Belt consists of heated and
deformed volcanic and sedimentary rocks. Specifically, the proposed project is located in felsic
metavolcanic rock (mapped CZfv) of the Carolina Slate Belt, which corresponds to the Uwharrie
Formation’s felsic voncaniclastic rocks and portions of the Cid Formation’s rhyolitic-rhyodactic
units. This unit consists of light gray to greenish gray, felsic metavolcanic rock interbedded with
mafic and intermediate metavolcanic rock and is composed primarily of feldspar, quartz, sericite,
chlorite meta-argillite, and metamudstone (NCGS, 1985). Note: This information was obtained from
geologic mapping no field investigations of rock lithology were performed.
Due to the lack of bed control (e.g., bedrock, etc.), fluvial erosion, and cattle trampling, the stream
has downcut along portions of the reach. The remainder of the Site has relatively confined valleys,
which constrict the floodplain, and limited alluvial deposits. Soils in these areas are typical of the
gently to moderately sloping upland areas of the Piedmont.
Soil mapping units are based on the U.S. Department of Agriculture (USDA) Natural Resources
Conservation Service (NRCS) Soil Survey for Chatham County. Soil types within the study area were
mapped with the NRCS Web Soil Survey and are described below in Table 4. A soils map based on
this information is provided in Figure 4. Note: no field mapping of soils was performed for this
project.
Table 4: Project Soil Types and Descriptions
Maney Farm Mitigation Project
Soil Name Location Description
Cid Silt Loam (6-10%) UT2
Cid silt loam is a strongly sloping, moderately deep
and moderately well drained soil found on upland
and interfluves. The soil forms in residuum from
Carolina Slate Belt rock and other fine grained rocks.
Cid-Lignum Complex
(2-6%) UTSF, UT1, UT 1B, and UT5
Cid-Lignum is found on gently sloping areas of the
upland. It is moderately well drained to somewhat
poorly drained. These soils have a loamy surface
layer and clayey subsoil.
Nanford-Badin
Complex (2-6%) UT4
Nanford-Badin complex is a well drained soil with
low flood potential. It is found on upland, hill slopes,
and ridges and consists of residuum weathered from
slate. Bedrock is within 40 to 60 inches of this soil.
Nanford-Badin
Complex (6-10%)
UTSF, UT1, UT2 UT3 and
UT4
Nanford-Badin complex at 6-10% slopes is found on
strong slopes on the side slopes of uplands. This soil
is deep and well drained. Bedrock is within 20 to 40
inches of this soil.
Source: Chatham County Soil Survey, USDA-NRCS, http://efotg.nrcs.usda.gov
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4.4 Valley Classification
The topography of the Site and surrounding area consist of gently rolling hills interspersed with
narrow valleys (Figure 5). The stream valleys have slopes ranging from 0.2-1.6% and valley side
slopes ranging from 5%-10%. UTSF has a narrow alluvial valley that expands and constricts between
widths of 150 and 250 feet. UT1, UT2, UT3, and UT4 transition from a constricted valley (<100 feet)
within the headwaters to a wider valley (>150 feet) as they approach the confluence with UTSF.
UT5 valley widths range between 150 and 200 feet.
4.5 Surface Water Classification and Water Quality
On May 28 and 29, 2014 Wildlands investigated on-site jurisdictional waters of the U.S. using the
U.S. Army Corps of Engineers (USACE) Routine On-Site Determination Method. This method is
defined in the 1987 Corps of Engineers Wetlands Delineation Manual and subsequent Eastern
Mountain and Piedmont Regional Supplement. Determination methods include stream
classification utilizing the NCDWR Stream Identification Form and the USACE Stream Quality
Assessment Worksheet. Potential jurisdictional wetland areas were classified using the USACE
Wetland Determination Data Form (refer to Section 5.1 below for more information on
jurisdictional wetlands).
The results of the on-site field investigation indicate that there are seven jurisdictional stream
channels located within the proposed project area that are all UTs to South Fork Cane Creek. Figure
6 illustrates the hydrologic features of the Site. Stream classification forms representative of on-site
jurisdictional channels have been enclosed in Appendix 4 (SCP1-SCP10). Site photographs are
included in Appendix 1. There is currently no best usage classification assigned by the NCDWR for
streams on this Site.
4.6 Existing Stream Condition
An existing conditions assessment was performed in May and June, 2014. The purpose of the
assessment was to characterize the existing morphology of the Site; identify incision, bank erosion,
lack of native vegetation, sedimentation, and poor habitat conditions; and to provide a basis for
developing a design to enhance the ecological function of the Site. The locations of the project
reaches and surveyed cross-sections are shown in Figure 6. Existing conditions geomorphic survey
data are included in Appendix 5. The reach summary information for each stream is summarized in
Table 5 and the existing geomorphic conditions are summarized in Table 6.
4.6.1 Unnamed Tributary to South Fork Cane Creek
UTSF is divided into two sections for existing conditions analysis. The channel slope and valley slope
for UTSF are typical for Piedmont streams in similar valley types (Table 6). The bed of UTSF is
predominately characterized by runs, with a few log/debris jams creating isolated pools. Livestock
have direct access to the stream, which has resulted in heavily trampled banks and an actively
eroding channel. The active scour zones and wallow areas are contributing to the fining of bed
material as evidenced by the reach-wide sediment characterization. Pebble-counts and sieve
analysis of sediment samples were utilized to characterize sediment within the existing channel and
to identify the predominant substrate as silt and sand. The channel classifies as a Rosgen E5.
Results of the existing conditions morphologic survey of UTSF Reach 1 and 2 are summarized in
Table 6 and the survey data is included in Appendix 5.
Vegetative buffers along the reach range from areas of mature trees to open pasture. The forested
buffer from the upstream extent to the confluence with UT2 averages 75 feet on each bank.
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However, cattle have extensively grazed and trampled the understory resulting in limited
vegetative regeneration and ground cover within this reach. The forested buffer from the
confluence with UT2 to the downstream extent is intermittent and disconnected. Canopy species
include American elm (Ulmus americana), sweetgum (Liquidambar styraciflua), green ash (Fraxinus
pennsylvanica), red maple (Acer rubrum), willow oak (Quercus phellos), and southern red oak
(Quercus falcata). Understory and herbaceous species were limited but include eastern red cedar
(Juniperus virginiana), coralberry (Symphoricarpos orbiculatus), Chinese privet (Ligustrum sinense),
soft rush (Juncus effusus), Japanese honeysuckle (Lonicera japonica), and Nepalese browntop
(Microstegium vimineum).
4.6.2 Unnamed Tributary 1
The UT1 drainage area is an intermittent system that is divided into three reaches for existing
conditions analysis. The majority of the drainage area to UT1 is primarily used for livestock grazing.
Livestock have direct access to the stream reaches, which has resulted in heavily trampled banks
and an actively eroding channel. The active scour zones and wallow areas are contributing to the
fining of bed material. Channel incision ranges from slight to moderate throughout the reaches.
The UT1 reaches classify as Rosgen B5 channel types. Results of the existing conditions morphologic
survey of UT1 are summarized in Table 6 and the survey data is included in Appendix 5.
Riparian vegetation along the UT1A reach is predominately managed herbaceous species
comprised of fescue (Fetsuca sp.), blackberry (Rubus sp.), coralberry, white clover (Trifolium
repens), buttercup species (Ranunculus spp.), and multiflora rose (Rosa multiflora). UT1B contains
mature trees within the riparian zone, but several mature trees were noted as stressed or dying
presumably as a result of root compaction from cattle trampling. The UT1C reach contains a narrow
corridor of mature trees with little to no middle and understory due to cattle grazing. Tree species
within the UT1 reaches include American elm, green ash, red maple, white oak (Quercus alba),
sweetgum, and willow oak.
4.6.3 Unnamed Tributary 2
UT2 begins as an intermittent stream and develops into a perennial system prior to its confluence
with UTSF. While UT2 has an intact mature riparian corridor, cattle have open access to the entire
reach and have heavily impacted the understory and herbaceous layers. While the majority of the
upper reach is impacted by cattle, the reach is relatively stable. The lower reach prior to the
confluence with UTSF has been heavily trampled by cattle. The UT2 reach classifies as Rosgen B5
channel types. Results of the existing conditions morphologic survey of UT2 are summarized in
Table 6 and the survey data is included in Appendix 5.
The vegetative buffers along the reach are approximately 200 feet on each bank and are
predominately comprised of mature trees. Canopy species along UT2 include American elm, green
ash, red maple, eastern red cedar, willow oak, white oak, hickory sp. (Carya sp.), and tulip poplar
(Liriodendron tulipifera). Understory and herbaceous species were limited but include coralberry,
Chinese privet, Japanese honeysuckle, and Nepalese browntop.
4.6.4 Unnamed Tributary 3
UT3 is an intermittent system within an active cattle pasture. While the entire reach is impacted by
cattle, the majority of the stream reach is relatively stable. The stream channel is no longer
discernable along the lower reach due to cattle trampling. The UT3 reach classifies as Rosgen E5b
channel type. Results of the existing conditions morphologic survey of UT3 are summarized in Table
6 and the survey data is included in Appendix 5.
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Riparian vegetation along the reach is predominately comprised of managed herbaceous layers
including fescue, white clover, Nepalese browntop, horseweed, and buttercup species. Scattered
canopy trees are present primarily within the upper extent of the reach and include red maple,
sugarberry (Celtis laevigata), willow oak, and tulip poplar. An isolated stand of green ash and
sugarberry with an understory of Chinese privet is located near the confluence with UTSF.
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Table 5: Reach Summary Information
Maney Farm Mitigation Project
UTSF
R1
UTSF
R2 UT1A UT1B UT1C UT2A UT2B UT3A UT3B UT4A UT4B UT5
Existing Length (LF) 2,298 1,209 390 102 166 485 44 418 84 217 40 778
Valley Slope (feet/ foot) 0.0131 0.0086 0.0187 0.0396 0.0187 0.0366 0.0366 0.0377 0.0377 0.0232 0.0232 0.0139
Drainage Area (acres) 115 211 16 4 19 11 11 10 10 20 20 76
Drainage Area (miles2) 0.18 0.33 0.02 0.01 0.03 0.02 0.02 0.02 0.02 0.03 0.03 0.12
NCDWR Stream ID Score 27/37 37 21 25.5 28 26/30 30 20.75 20.75 22.5 22.5 32.5
Perennial (P) or
Intermittent (I) I/P P I I I I/P P I I I I P
NCDWR Classification N/A
Rosgen Classification of
Existing Conditions E5 E5 B5 - B5 B5 B5 E5b E5b E5b E5b E5
Simon Evolutionary Stage II/IV II/IV III V II/IV II/V II/V V/VI V/VI II/V II/V II/III
FEMA Zone Classification X
Note: The Rosgen classification system is for natural streams. These channels have been heavily manipulated and impacted by livestock trampling and therefore
the Rosgen classification system is used to describe an approximate description of stream type only.
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Table 6: Stream Existing Conditions
Maney Farm Mitigation Project
Parameter Notation Units
UTSF-R1 UTSF-R2 UT1A UT1B UT1C UT2A UT2B UT3A UT3B UT4A UT4B UT5
min max min max min max min max min max min max min max min max min max min max min max min max
stream type E5 E5 B5 - B5 B5 B5 E5b E5b E5b E5b E5
drainage area DA sq mi 0.18 0.33 0.02 0.01 0.03 0.02 0.02 0.02 0.02 0.03 0.03 0.12
bankfull cross-sectional area Abkf SF 4.1 7.1 5.4 5.6 2.1 - 2.1 1.1 1.1 1.1 1.1 1.9 1.9 3.5
avg velocity during bankfull event vbkf fps 2.8 4.8 3.4 3.6 3.1 - 3.0 3.4 3.4 3.2 3.2 3.0 3.0 2.1
width at bankfull wbkf feet 3.2 12.0 4.7 8.2 5.8 - 4.1 2.6 2.6 2.2 2.2 4.4 4.4 5.7
maximum depth at bankfull dmax feet 1.2 2.0 1.5 0.6 - 0.8 0.5 0.5 0.8 0.8 1.0 1.0 1.2
mean depth at bankfull dbkf feet 0.6 1.3 0.7 1.2 0.4 - 0.5 0.4 0.4 0.5 0.5 0.4 0.4 0.6
bankfull width to depth ratio wbkf/dbkf 2.5 20.4 4.0 12.3 15.9 - 8.1 6.2 6.2 4.6 4.6 9.9 9.9 9.1
low bank height feet 2.6 2.7 2.1 2.9 1.5 - 1.8 2.9 2.9 1.7 1.7 1.4 1.4 1.6
bank height ratio BHR 1.3 2.2 1.4 1.9 2.3 - 2.3 5.4 5.4 2.2 2.2 1.4 1.4 1.4
max pool depth at bankfull dpool feet 1.5 1.8 1.8 2.0 - - - - - - - - - 1.4
pool depth ratio dpool/dbkf 1.4 2.5 1.7 2.6 - - - - - - - - - 2.3
pool width at bankfull wpool feet 5.6 7.2 7.0 7.5 - - - - - - - - - 3.7
pool width ratio wpool/wbkf 0.6 1.8 0.9 1.5 - - - - - - - - 0.7
Bkf pool cross-sectional area Apool SF 6.6 7.2 8.5 11.1 - - - - - - - - - 3.4
pool area ratio Apool/Abkf 1.0 1.6 1.6 2.0 - - - - - - - - 1.0
floodprone area width wfpa feet 15.2 50.0 69.8 82.0 10.6 - 5.3 4.4 4.4 11.4 11.4 23.3 23.3 40.0
entrenchment ratio ER 1.4 12.5 10.0 14.8 1.8 - 1.3 1.7 1.7 5.1 5.1 5.3 5.3 7.1
valley slope Svalley feet/ foot 0.0131 0.0086 0.0187 0.0396 0.0187 0.0366 0.0366 0.0377 0.0377 0.0232 0.0232 0.0139
channel slope Schannel feet/ foot 0.0090 0.0057 0.01282 0.0323 0.0186 0.0195 0.0157 0.0383 0.0291 0.0259 0.0651 0.0112
sinuosity K 1.34 1.33 1.10 1.16 1.17 1.12 1.04 1.09 1.00 1.14 1.06 1.34
belt width wblt feet 5 42 10 37 8 22 6 9 10 18 4 26 1 2 26 27 - - 4 13 2 3 3 18
meander width ratio wblt/wbkf 1.6 3.5 2.1 4.5 1.4 3.8 - 2.4 4.4 1.5 10.0 0.4 0.8 11.8 12.3 - - 0.9 3.0 0.5 0.7 0.5 3.2
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Parameter Notation Units
UTSF-R1 UTSF-R2 UT1A UT1B UT1C UT2A UT2B UT3A UT3B UT4A UT4B UT5
min max min max min max min max min max min max min max min max min max min max min max min max
meander length Lm feet 18 100 21 59 47 155 28 36 54 63 5 15 12 131 131 - - 29 44 11 22 16 58
meander length ratio Lm/wbkf 5.6 8.3 4.5 7.2 8.1 26.7 - 13.2 15.4 1.9 5.8 4.6 60.0 72.7 - - 6.6 10.0 2.5 5.0 2.8 10.2
radius of curvature Rc feet 4 25 5 13 6 20 7 9 9 16 3 16 1 3 25 25 - - 3 11 2 3 3 14
radius of curvature ratio Rc/wbkf 1.3 2.1 1.1 1.6 1.0 3.5 - 2.2 3.9 1.2 6.2 0.4 1.2 11.4 15.0 - - 0.7 2.5 0.5 0.7 0.5 2.5
Particle Size Distribution from Reachwide Pebble Count / Sieve Analysis
d50 Description Medium
Sand Silt/Clay N/A N/A N/A N/A N/A N/A N/A N/A N/A Silt/Clay
d16 mm Silt/Clay Silt/Clay N/A N/A N/A N/A N/A N/A N/A N/A N/A Silt/Clay
d35 mm Very Fine Sand Silt/Clay N/A N/A N/A N/A N/A N/A N/A N/A N/A Silt/Clay
d50 mm Medium Sand Silt/Clay N/A N/A N/A N/A N/A N/A N/A N/A N/A Silt/Clay
d84 mm 11.08 6.1 N/A N/A N/A N/A N/A N/A N/A N/A N/A 8.9
d95 mm 15.41 28.5 N/A N/A N/A N/A N/A N/A N/A N/A N/A 22.6
d100 mm 22.6 180 N/A N/A N/A N/A N/A N/A N/A N/A N/A 64
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4.6.5 Unnamed Tributary 4
Livestock have direct access to UT4 which has resulted in trampled bed and banks throughout the
reach. The lower reach near the confluence of UTSF has areas of active headcuts and unstable
banks. Vegetative buffers along the reach range from areas with narrow strips of mature trees to
open pasture. The UT4 reach classifies as Rosgen E5b channel type. Results of the existing
conditions morphologic survey of UT4 are summarized in Table 6 and the survey data is included in
Appendix 5.
Canopy species along this reach include white oak, sweetgum, eastern red cedar, and green ash.
Understory species include American holly (Ilex opaca), eastern red cedar, and American elm. The
shrub and herbaceous layer primarily included Chinese privet, coralberry, Nepalese browntop,
fescue, white clover, and buttercup.
4.6.6 Unnamed Tributary 5
UT5 begins in a heavily forested area in which cattle have been excluded. The impacted reach in
which cattle have access ranges from areas of mature over-story in the upper extent to managed
herbaceous layers near the confluence with UTSF. Deposition of fine material is apparent along the
impacted portion of this stream. Results of the existing conditions morphologic survey of UT4 are
summarized in Table 6 and the survey data is included in Appendix 5.
Canopy species include American elm, green ash, red maple, willow oak, southern red oak.
Understory and herbaceous species were limited but include black willow (Salix nigra), eastern red
cedar, coralberry, Chinese privet, and Nepalese browntop. Existing condition surveys showed areas
of incision along with trampled bed and banks. The incision and cattle trampling have resulted in a
fining of bed material with a median particle size of silt/clay. The UT5 reach classifies as Rosgen E5
channel type. Results of the existing conditions morphologic survey of UT4 are summarized in Table
6 and the survey data is included in Appendix 5.
4.7 Channel Evolution
The presence of livestock and agricultural land use practices have prevented the channels from
evolving from disturbed to stable conditions. For this reason, the historic condition of the channels
is discussed below but a detailed discussion of channel evolution is not warranted.
According to the historical aerial photographs, the land use on-site has been hay or livestock
production since 1972. The riparian buffer widths were reduced prior to the early 1970s to
maximize the area available for agricultural practices. The extent of riparian buffers on site and
within the contributing watershed have remained essentially unchanged since. These historic
landscape disturbances likely resulted in higher discharge and sediment loads to project streams
which would have perturbed the system and resulted in morphologic changes. However, the land
cover alterations likely ceased quickly in which case the channels would have re-stabilized.
However, on-going livestock access has resulted in continual trampling of the stream beds and
banks and this, along with a lack of riparian vegetation along much of the project stream length,
has prevented the channels from progressing to stables forms.
The propagation of headcuts through the project reaches have been arrested by large roots and
debris jams which are the primary sources of grade control. However, incision that resulted from
headcuts remains along some reaches and contributes to the instability of the system. Bank failures
through mass wasting were observed along portions of the project. The channels will not progress
Maney Farm Mitigation Project
Final Mitigation Plan Page 13
to a stable, equilibrium state until livestock are removed from the streams, stable channel
dimensions are established, and incision is corrected.
4.8 Channel Stability
Wildlands utilized a modified version of the Rapid Assessment of Channel Stability as described in
Hydrologic Engineering circular (HEC)-20 (Lagasse et al., 2001). The method is semi-qualitative and
incorporates 13 stability indicators that are evaluated in the field. In a 2006 publication, the Federal
Highway Administration (FHWA) updated the method for HEC-20 by modifying the metrics included
in the assessment and incorporating a stream type determination. The result is an assessment
method that can be rapidly applied on a variety of stream types in different physiographic settings
with a range of bed and bank materials.
The Channel Stability Assessment protocol was designed to evaluate 13 parameters. Once all
parameters are scored, the stability of the stream is classified as Excellent, Good, Fair, or Poor. As
the protocol was designed to assess stream channel stability near bridges, two minor modifications
were made to the methodology to make it more applicable to project specific conditions. The first
modification involved adjusting scoring so that naturally meandering streams score lower (better
condition) than straight and/or engineered channels. Because straight, engineered channels are
hydraulically efficient and necessary for bridge protection, they score low (excellent to good rating)
with the original methodology. Secondly, the last assessment parameter – upstream distance to
bridge – was removed from the protocol because it relates directly to the potential effects of
instability on a bridge and should not influence stability ratings for the streams for this project. The
final scores and corresponding ratings were based on the 12 remaining parameters. The rating
adjectives were assigned to the streams based on the FHWA guidelines for pool-riffle stream types.
The HEC-20 manual also describes both lateral and vertical components of overall channel stability,
which can be separated with this assessment methodology. Some of the parameters described
above relate specifically to either vertical or horizontal stability. When all parameter scores for the
vertical category or all parameter scores for the horizontal category are summed and normalized
by the total possible scores for their respective categories, a vertical or horizontal fraction is
produced. These fractions may then be compared to one another to determine if the channel is
more vertically or horizontally unstable.
The assessment results for the streams on the Site are shown in Table 7 and the forms are included
in Appendix 6. Reaches UT1A, UT1C, UT2A/B, UT3A/B, and UT4A/B were all rated good whereas
UTSF R1, UTSF R2, UT1B, and UT5 were all rated as fair. The vertical and lateral fractions for UT1A,
UT1C, UT2A/B, UT3A/B, and UT4A/B are similar indicating that the streams are no more laterally
unstable than vertically unstable. These reaches are considered fairly stable for most of their length
and enhancement activities are the proposed mitigation approach, though redesign of the
downstream ends of each channel is required in order to connect these streams to the restored
UTSF reach. For UTSF, UT1B, and UT5 the lateral fraction is larger than the vertical fraction
indicating that, although some incision may have occurred, the streams are more laterally unstable
than vertically unstable. The lateral instability is related to a combination of factors including
livestock trampling, mass wasting, and fluvial erosion. Due to the fairly significant lateral instability
of these reaches, a restoration approach is proposed. While UT1B falls within this category of
significant lateral instability (almost completely related to livestock trampling), restoration is not
proposed for this very small drainage.
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Table 7: Existing Conditions Channel Stability Assessment Results
Maney Farm Mitigation Project
Parameter
UTSF
R1
UTSF
R2
UT1
A & C UT1B UT2
A & B
UT3
A & B
UT4
A & B UT5
1. Watershed
characteristics 10 10 11 11 6 6 6 4
2. Flow habit 1 1 7 7 3 3 3 1
3. Channel pattern 8 8 5 7 3 4 4 9
4. Entrenchment 4 4 3 2 7 3 3 6
5. Bed material 8 8 9 10 7 10 7 9
6. Bar development 1 1 3 3 3 3 3 10
7. Obstructions 8 8 4 4 4 2 3 4
8. Bank soil texture and
coherence 3 3 4 4 4 3 3 5
9. Average bank slope
angle 10 10 6 6 7 7 7 11
10. Bank protection 10 10 7 9 6 4 7 11
11. Bank cutting 11 9 6 9 4 4 4 8
12. Mass wasting or bank
failure 9 9 6 9 4 7 4 9
Score 83 81 71 81 58 56 54 87
Ranking Fair Fair Good Fair Good Good Good Fair
Lateral Score 43 41 29 37 25 25 25 44
Vertical Score 13 13 15 15 17 16 13 25
Lateral Fraction 72% 68% 48% 62% 42% 42% 42% 73%
Vertical Fraction 36% 36% 42% 42% 47% 44% 36% 69%
4.9 Utilities and Site Access
There are no underground or overhead utilities on the Site. There is an existing culvert under a
state maintained road at the upstream end of UTSF and UT1B (Center Church Road). The project
will not affect these culverts and they will remain in place in their current configuration. There is
one 25 foot wide proposed easement break that will include a culverted crossing. The crossings will
be fenced both upstream and downstream to permanently prevent livestock access and provide
better protection of the riparian area. This crossing area is not included in the mitigation credit
calculation for the Site. The Site is accessible from a farm road and pasture access gates off of
Center Church Road.
5.0 REGULATORY CONSIDERATIONS
5.1 401/404
On May 28 and 29, 2014 Wildlands investigated on-site jurisdictional Waters of the U.S. within the
proposed project easement area. Jurisdictional areas were delineated using the USACE Routine On-
Site Determination Method. This method is defined by the 1987 Corps of Engineers Wetlands
Delineation Manual and subsequent Eastern Mountain and Piedmont Regional Supplement.
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Wetland determination Data Forms representative of on-site jurisdictional areas as well as non-
jurisdictional upland areas have been included in Appendix 7. All jurisdictional waters of the U.S.
were surveyed by Turner Land Surveying, PLLC.
The results of the on-site field investigation indicate that there are seven jurisdictional stream
channels located within the proposed project area that are all unnamed tributaries to South Fork
Cane Creek (UTSF, UT1{Reach A and C}, UT1B, UT2{Reach A and B}, UT3{Reach A and B}, UT4{Reach
A and B}, and UT5). UTSF downstream of the confluence with UT1, the lower half of UT2, and UT5
are classified as perennial channels. UT1, UT1B, the upper extent of UT2, UT3, and UT4 are
classified as an intermittent stream channels.
Twenty one jurisdictional wetland areas, ranging from 0.003 to 0.203 acres, were identified within
or immediately adjacent to the proposed project area (Wetland A-U) and are located within the
floodplains of the unnamed tributaries. These 21 areas are considered wetland inclusions in non-
wetland soils. Wetlands A, B, D, F, L, and N – U were classified as bottomland hardwood forest
using the North Carolina Wetland Assessment Method (NCWAM) classification key and the
evaluator’s best professional judgment. Wetlands C, E, G-K, and M were classified as seeps. On-site
wetland features exhibited saturation within the upper 12 inches of the soil profiles, low chroma
soils, drainage patterns, and/or pockets of shallow inundation. Common hydrophytic vegetation
included American elm, green ash, shallow sedge, and soft rush. Characteristics of wetlands A-U
are described in Table 8.
The design of the Site is focused on minimizing impacts to the wetlands and protecting wetland
areas with a conservation easement. All wetland areas inside the limits of disturbance will be
flagged with safety fence during construction to prevent unintended impacts. This will be denoted
in the final construction plans Erosion and Sediment Control sheets, details and specifications.
Potential impacts to existing wetlands are detailed in the Pre-Construction Notification enclosed in
Appendix 8 and illustrated on the final Construction Plans.
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Table 8: Wetland Summary Information
Maney Farm Mitigation Project
A B C D E F G
Size of Wetland
(acres) 0.006 0.010 0.034 0.005 0.051 0.003 0.008
Wetland Type
Bottomland
Hardwood
Forest
Bottomland
Hardwood
Forest
Seep
Bottomland
Hardwood
Forest
Seep
Bottomland
Hardwood
Forest
Seep
Mapped Soil
Series Cid-Lignum Cid-Lignum Cid-Lignum /
Naford-Badin Cid-Lignum Cid-Lignum /
Naford-Badin Cid-Lignum Cid-Lignum
Drainage Class
Moderately
to Somewhat
Poorly
Drained
Moderately
to Somewhat
Poorly
Drained
Well to
Somewhat
Poorly
Drained
Moderately
to Somewhat
Poorly
Drained
Well to
Somewhat
Poorly
Drained
Moderately
to Somewhat
Poorly
Drained
Moderately
to Somewhat
Poorly
Drained
Soil Hydric Series Wehadkee,
Undrained
Wehadkee,
Undrained
Wehadkee,
Undrained
Wehadkee,
Undrained
Wehadkee,
Undrained
Wehadkee,
Undrained
Wehadkee,
Undrained
Source of
Hydrology
Groundwater
/ Overbank
Flooding
Groundwater
/ Overbank
Flooding
Groundwater
Seep
Groundwater
/ Overbank
Flooding
Groundwater
Seep
Groundwater
/ Overbank
Flooding
Groundwater
Seep
Hydrologic
Impairment N/A N/A N/A N/A N/A N/A N/A
Native
Vegetation
Community
Bottomland
Hardwood
Forest
Bottomland
Hardwood
Forest
Bottomland
Hardwood
Forest
Bottomland
Hardwood
Forest
Bottomland
Hardwood
Forest
Bottomland
Hardwood
Forest
Bottomland
Hardwood
Forest
% Composition
Invasive Species 0% 5% 5% 10% 0% 10% 10%
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Table 8: Wetland Summary Information
Maney Farm Mitigation Project
H I J K L M N
Size of Wetland
(acres) 0.012 0.007 0.008 0.203 0.015 0.023 0.029
Wetland Type Seep Seep Seep Seep
Bottomland
Hardwood
Forest
Seep
Bottomland
Hardwood
Forest
Mapped Soil
Series Cid-Lignum Naford-Badin Naford-Badin Naford-Badin Cid-Lignum /
Cid Silt Loam Cid-Lignum Cid-Lignum
Drainage Class
Moderately
to Somewhat
Poorly
Drained
Well Drained Well Drained Well Drained
Moderately
Well to
Somewhat
Poorly
Drained
Moderately
to Somewhat
Poorly
Drained
Moderately
to Somewhat
Poorly
Drained
Soil Hydric Series Wehadkee,
Undrained N/A N/A N/A Wehadkee,
Undrained
Wehadkee,
Undrained
Wehadkee,
Undrained
Source of
Hydrology
Groundwater
Seep
Groundwater
Seep
Groundwater
Seep
Groundwater
Seep
Groundwater
/ Overbank
Flooding
Groundwater
Seep
Groundwater
/ Overbank
Flooding
Hydrologic
Impairment N/A N/A N/A N/A N/A N/A N/A
Native
Vegetation
Community
Bottomland
Hardwood
Forest
Bottomland
Hardwood
Forest
Bottomland
Hardwood
Forest
Bottomland
Hardwood
Forest
Bottomland
Hardwood
Forest
Bottomland
Hardwood
Forest
Bottomland
Hardwood
Forest
% Composition
Invasive Species 5% 5% 5% 1% 10% 5% 10%
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Table 8: Wetland Summary Information
Maney Farm Mitigation Project
O P Q R S T U
Size of Wetland
(acres) 0.011 0.014 0.176 0.019 0.005 0.009 0.010
Wetland Type
Bottomland
Hardwood
Forest
Bottomland
Hardwood
Forest
Bottomland
Hardwood
Forest
Bottomland
Hardwood
Forest
Bottomland
Hardwood
Forest
Bottomland
Hardwood
Forest
Bottomland
Hardwood
Forest
Mapped Soil
Series Cid-Lignum Cid-Lignum Cid-Lignum Cid-Lignum Cid-Lignum Cid-Lignum Cid-Lignum
Drainage Class
Moderately
to Somewhat
Poorly
Drained
Moderately
to Somewhat
Poorly
Drained
Moderately
to Somewhat
Poorly
Drained
Moderately
to Somewhat
Poorly
Drained
Moderately
to Somewhat
Poorly
Drained
Moderately
to Somewhat
Poorly
Drained
Moderately
to Somewhat
Poorly
Drained
Soil Hydric Series Wehadkee,
Undrained
Wehadkee,
Undrained
Wehadkee,
Undrained
Wehadkee,
Undrained
Wehadkee,
Undrained
Wehadkee,
Undrained
Wehadkee,
Undrained
Source of
Hydrology
Groundwater
/ Overbank
Flooding
Groundwater
/ Overbank
Flooding
Groundwater
/ Overbank
Flooding
Groundwater
/ Overbank
Flooding
Groundwater
/ Overbank
Flooding
Groundwater
/ Overbank
Flooding
Groundwater
/ Overbank
Flooding
Hydrologic
Impairment N/A N/A N/A N/A N/A N/A N/A
Native
Vegetation
Community
Bottomland
Hardwood
Forest
Bottomland
Hardwood
Forest
Bottomland
Hardwood
Forest
Bottomland
Hardwood
Forest
Bottomland
Hardwood
Forest
Bottomland
Hardwood
Forest
Bottomland
Hardwood
Forest
% Composition
Invasive Species 10% 15% 10% 0% 10% 15% 5%
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5.2 Threatened and Endangered Species
5.2.1 Site Evaluation Methodology
The Endangered Species Act (ESA) of 1973, amended (16 U.S.C. 1531 et seq.), defines protection for
species with Federal Classification of Threatened (T) or Endangered (E). An “Endangered Species” is
defined as “any species which is in danger of extinction throughout all or a significant portion of its
range” and a “Threatened Species” is defined as “any species which is likely to become an
Endangered Species within the foreseeable future throughout all or a significant portion of its
range” (16 U.S.C. 1532).
Wildlands utilized the US Fish and Wildlife Service (USFWS) and NC Natural Heritage Program (NHP)
databases to search for federally listed threatened and endangered plant and animal species in
Chatham County, NC. Four federally listed species; the red-cockaded woodpecker (Picoides
borealis), the bald eagle (Haliaeetus leucocephalus), Cape Fear shiner (Notropis mekistocholas),
and harperella (Ptilimnium nodosum) are currently listed in Chatham County (Table 8). The
Categorical Exclusion (included in Appendix 9) has been approved by the Federal Highway
Administration.
Table 9: Listed Threatened and Endangered Species in Chatham County, NC
Maney Farm Mitigation Project
Species Federal
Status Habitat Biological
Conclusions
Vertebrate
Red-cockaded woodpecker
(Picoides borealis) E Open stands of mature
pines No affect
Bald eagle
(Haliaeetus leucocephalus) BGPA
Near large open water
bodies: lakes, marshes,
seacoasts, and rivers
May affect, but
not likely to
adversely affect
Cape Fear shiner
(Notropis mekistocholas) E
Pools, riffles, and runs of
rocky, clean freshwater
streams
No affect
Vascular Plant
Harperella
(Ptilimnium nodosum) E Rocky or gravely sholas of
clear swift-moving streams
May affect, but
not likely to
adversely affect
BGPA = Bald and Golden Eagle Protection Act
5.2.2 Threatened and Endangered Species Descriptions
Red-cockaded woodpecker
The red-cockaded woodpecker is a medium-sized woodpecker species (8 to 9 inches in length).
Distinctive coloration includes black and white feathers with a large white cheek patch and a black
back with a white barred pattern. This species is typically found year-round in large open stands of
pines with mature trees of 60+ years in age. The foraging habitat for this species may include pine
hardwood stands of longleaf and southern pine, 30+ years in age. Occurrences of the red-cockaded
woodpecker are listed as historic within Chatham County.
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Bald eagle
The bald eagle is a very large raptor species, typically 28 to 38 inches in length. Adult individuals are
brown in color with a very distinctive white head and tail. Bald eagles typically live near large
bodies of open water with suitable fish habitat including lakes, marshes, seacoasts, and rivers. This
species generally requires tall, mature tree species for nesting and roosting. Bald eagles were de-
listed from the Endangered Species List in June 2007; however, this species remains under the
protection of the Migratory Bird Treaty Act and the Bald and Golden Eagle Protection Act (BGPA).
This species is known to occur in every U.S. state except Hawaii.
Cape Fear shiner
The Cape Fear shiner is a small minnow fish species, typically 2 inches in length. This species is pale
silvery yellow in color with a black stripe along each side and yellow fins. Water willow beds in
flowing areas of creeks and rivers appear to be part of the essential habitat for this species.
Individuals can be found in pools, riffles, and slow runs of clean, rocky streams composed of gravel,
cobble, and boulder substrates. Critical habitat for this species within Chatham County includes
approximately 4.1 miles of the Rocky River from the NC-902 bridge downstream to the County
Road 1010 Bridge. Additional critical habitat includes 0.5 mile of Bear Creek from the County Road
2156 bridge downstream to the Rocky River and 4.2 miles downstream within the Rocky River to
2.6 miles of the Deep River.
Harparella
Harperella is an obligate, annual vascular plant ranging in height from 6 to 36 inches. This plant
exhibits small white clusters of flowers at the stem tops similar to Queen Anne’s lace. This species
typically flowers from May until the first frost. Ideal habitat for this species includes pond and
riverine areas with gravelly shoals of clear, swift-flowing streams. These areas typically require
moderately intensive spring floods to scour gravel bars and rock crevices to remove any competing
vegetation. Known population occurrences of harperella have been observed in Chatham County
within the past 20 years.
5.2.3 Biological Conclusions
Based on a pedestrian survey of the Site that was performed on May 28 and 29, 2014; no individual
species or critical habitat was found to exist on the Site.
Wildlands requested comment on the project from both the USFWS and the North Carolina Wildlife
Resource Commission (NCWRC) on February 26, 2014. NCWRC responded on March 14, 2014 and
stated they “do not anticipate the project to result in significant adverse impacts to aquatic and
terrestrial resources.” The USFWS responded on April 4, 2014 and concurred with NCWRC stating
that “the proposed action is not likely to adversely affect any federally-listed endangered or
threatened species, their formally designated critical habitat, or species currently proposed for
listing under the Act.” All correspondence is located in Appendix 9.
5.3 Cultural Resources
5.3.1 Site Evaluation Methodology
The National Historic Preservation Act (NHPA) of 1966, as amended (16 U.S.C. 470), defines the
policy of historic preservation to protect, restore, and reuse districts, sites, structures, and objects
significant in American history, architecture, and culture. Section 106 of the NHPA mandates that
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federal agencies take into account the effects of their undertakings on any property that is included
in, or is eligible for inclusion in, the National Register of Historic Places.
5.3.2 SHPO/THPO Concurrence
Wildlands requested review and comment from the State Historic Preservation Office (SHPO) with
respect to any archeological and architectural resources related to the Site on February 26, 2014.
The SHPO responded on March 24, 2014 and stated they were not aware of any historic resources
that would be affected by the project. All correspondence related to this is located in Appendix 9.
5.4 FEMA Floodplain Compliance and Hydrologic Trespass
The Site is represented on the Chatham County Flood Insurance Rate Map Panels 8784 and 8796
(Figure7). There are no Federal Emergency Management Agency (FEMA) regulated floodplain areas
on the Site. Email correspondence with the Chatham County Public Works Director pertaining to
floodplain development permitting is included in Appendix 10 along with the FEMA/DMS checklist.
The project will be designed so that any increase in flooding will be contained on the Site and will
not extend upstream to adjacent parcels, so hydrologic trespass will not be a concern. The
proposed restoration has been designed to transition back to the existing boundary conditions in a
gradual manner.
6.0 REFERENCE SITES
6.1 Reference Streams
Reference streams provide geomorphic parameters of a stable system, which can be used to design
stable channels of similar stream types in similar landscapes and watersheds. Four reference
reaches were identified near the Site and used to support the design of the proposed restoration
(Figure 8). A range of reference reach metrics were utilized in order to properly tie in the
enhancement reach confluences with the restoration reaches. These reference reaches were
chosen because of their similarities to the project streams to be restored including drainage area,
valley slope, morphology, and bed material. The reference reaches are within the Carolina Slate
Belt region of the Piedmont. Geomorphic parameters for these reference reaches are summarized
in Table 10.
6.2 Channel Morphology and Classification of Reference Streams
The Agony Acres reference reach (UT1A – Reach 1) is located in northeast Guildford County, NC. It
was identified as a high quality preservation area on the Agony Acres Mitigation Site in the
mitigation plan submitted in March, 2014 and was used as a reference reach for that project.
Wildlands performed a detailed morphologic survey in March of 2013. The Agony Acres reference
reach has a drainage area of 0.3 square miles and is classified as a Rosgen E4 stream type. While
the slope range on the reference reach is slightly higher than the design reach, this reference site
was specifically chosen because of a similar drainage area and discharge as that of UTSF.
The UT to Cane Creek reference reach is located in southern Alamance County and is classified as a
Rosgen E4 stream type. Wildlands conducted a site visit and surveyed an additional cross section
typical of the reference reach in 2012. The reach has a drainage area of 0.28 square miles and flows
through a mature forest. The site is similar to stream reaches at Maney Farm in valley type and
slope.
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The UT to Varnals reference reach is located in south central Alamance County, NC near the Cane
Creek Mountains. The site was identified by EcoLogic Associates and used as a reference reach for
the Reedy Branch stream restoration site (EcoLogic Associates, 2002). Wildlands visited UT to
Varnals in September, 2014 and visually confirmed that the land use is unchanged from reported
conditions and that the stream is laterally and vertically stable. Wildlands conducted a detailed
morphological survey in October, 2014. UT to Varnals has a drainage area of 0.41 square miles and
is classified as a Rosgen E4 stream type for the majority of the reach. There are portions of the
stream where the valley constricts reducing the entrenchment ratio below those typical for Rosgen
type E channels and more towards those typical for Rosgen B type channels. This shift between a B
and E type channels suits the design for tying in the UT1, UT2, UT3, and UT4 reaches to UTSF.
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Table 10: Summary of Reference Reach Geomorphic Parameters
Maney Farm Mitigation Project
Notation Units Agony Acres UT1A - Reach 1 UT to Cane Creek UT to Varnals Creek
Min Max Min Max Min Max
stream type E4 E4 E4
drainage area DA sq mi 0.30 0.29 0.41
design discharge Q cfs 25.3 40.0 54.0
bankfull cross-sectional area Abkf SF 10.7 11.3 8.9 12.2 10.3 12.3
average velocity during
bankfull event vbkf fps 2.2 2.4 3.8 4.4 5.2
width at bankfull wbkf feet 9.1 10.4 11.5 12.3 9.3 10.5
maximum depth at bankfull dmax feet 1.8 1.2 1.6 1.5 1.7
mean depth at bankfull dbkf feet 1.0 1.2 0.8 1.0 1.1 1.2
bankfull width to depth ratio wbkf/dbkf 7.3 10.1 12.3 14.4 8.1 9.3
depth ratio dmax/dbkf feet 1.8 1.5 1.6 1.4
bank height ratio BHR 1.0 N/A 0.9 1.0
floodprone area width wfpa feet >36 31 20 64
entrenchment ratio ER >3.9 2.5 2.7 1.9 6.1
valley slope Svalley feet/ foot 0.010 0.034 0.026 0.020
channel slope Schnl feet/ foot 0.004 0.028 0.015 0.017
riffle slope Sriffle feet/ foot N/A 0.0188 0.0704 0.024 0.057
riffle slope ratio Sriffle/Schnl N/A 1.3 4.7 1.4 3.4
pool slope Sp feet/ foot N/A 0.001 0.011 0.000 0.015
pool slope ratio Sp/Schnl N/A 0.0 0.7 0.0 0.9
pool-to-pool spacing Lp-p feet N/A 27 73 8 82
pool spacing ratio Lp-p/wbkf N/A 2.3 6.1 0.5 5.6
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Notation Units Agony Acres UT1A - Reach 1 UT to Cane Creek UT to Varnals Creek
Min Max Min Max Min Max
pool cross-sectional area Apool SF 14.5 11.9 22.0 22.7
pool area ratio Apool/Abkf 1.3 1.0 1.3 1.8 1.9
maximum pool depth dpool feet 2.5 1.8 2.3 2.5 2.6
pool depth ratio dpool/dbkf 2.3 2.3 3.0 3.1
pool width at bankfull wpool feet 9.4 8.5 15.1 18.6
pool width ratio wpool/wbkf 1.0 0.7 1.0 1.3
sinuosity K 1.35 1.40 1.20
belt width wblt feet 21 93 102 15 45
meander width ratio wblt/wbkf 2.3 8.9 8.3 8.9 1.0 3.0
meander length Lm feet -- -- -- -- -- --
meander length ratio Lm/wbkf -- -- -- -- -- --
radius of curvature Rc feet 14 60 23 38 8 47
radius of curvature ratio Rc/ wbkf 1.5 5.8 2.0 3.1 0.6 3.2
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7.0 DETERMINATION OF CREDITS
Mitigation credits presented in Table 11 are projections based on site design. Upon completion of
site construction, the project components and credits data will be revised to be consistent with the
as-built condition.
Table 11: Determination of Credits
Maney Farm Mitigation Project
Mitigation Credits
Stream Riparian
Wetland
Non-riparian
wetland Buffer Nitrogen
Nutrient Offset
Phosphorus Nutrient
Offset
Type R RE R RE R RE
Totals 4,922 0 N/A N/A N/A N/A N/A N/A N/A
Project Components
Project
Component
or Reach ID
Existing
Footage/
Acreage
Proposed
Stationing
Location
Approach
(P1, P2, etc)
Restoration (R)
or Restoration
Equivalent (RE)
Restoration
Footage or
Acreage
Mitigation
Ratio
Proposed
Credit
UTSF-R1 2,298 100+00-121+63 P1 R 2,122 1:1 2,122
UTSF-R2 1,209 121+63 - 132+24 P1 R 1,061 1:1 1,061
UT1A 390 250+00 - 253+90 E2 R 390 2.5:1 156
UT1B 101 199+08 - 200+00 E2 R 92 2.5:1 37
UT1C 166 200+00 - 202+60 E1 R 260 1.5:1 173
UT2A 485 295+15 - 300+00 E2 R 484 2.5:1 194
UT2B 44 300+00 - 300+74 E1 R 73 1.5:1 49
UT3A 418 395+79 - 400+00 E2 R 421 2.5:1 168
UT3B 84 400+00 - 401+63 E1 R 162 1.5:1 108
UT4A 217 497+87 - 500+00 E2 R 212 2.5:1 85
UT4B 40 500+00 - 501+38 E1 R 138 1.5:1 92
UT5 778 602+00 - 608+77 P1 R 677 1:1 677
Component Summation
Restoration Level Stream (LF)
Riparian
Wetland
(Acres) Non-Riparian Wetland (AC)
Buffer
(sq.ft.)
Upland
(AC)
Restoration 3,860 N/A N/A N/A N/A
Enhancement N/A N/A N/A N/A N/A
Enhancement I 633 N/A N/A N/A N/A
Enhancement II 1,599 N/A N/A N/A N/A
Creation N/A N/A N/A N/A N/A
Preservation N/A N/A N/A N/A N/A
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8.0 CREDIT RELEASE SCHEDULE
All credit releases will be based on the total credit generated as reported by the as-built survey of
the mitigation site. Under no circumstances shall any mitigation project be debited until the
necessary DA authorization has been received for its construction or the District Engineer (DE) has
otherwise provided written approval for the project in the case where no DA authorization is
required for construction of the mitigation project. The DE, in consultation with the Interagency
Review Team (IRT), will determine if performance standards have been satisfied sufficiently to
meet the requirements of the release schedules below. In cases where some performance
standards have not been met, credits may still be released depending on the specifics of the case.
Monitoring may be required to restart or be extended, depending on the extent to which the Site
fails to meet the specified performance standard. The release of project credits will be subject to
the criteria described in Table 12.
Table 12: Credit Release Schedule – Stream Credits
Maney Farm Mitigation Project
Monitoring
Year Credit Release Activity Interim
Release
Total
Released
0 Initial Allocation – see requirements below 30% 30%
1 First year monitoring report demonstrates performance
standards are being met 10% 40%
2 Second year monitoring report demonstrates performance
standards are being met 10% 50%
(60%*)
3 Third year monitoring report demonstrates performance
standards are being met 10% 60%
(70%*)
4 Fourth year monitoring report demonstrates performance
standards are being met 5% 65%
(75%*)
5 Fifth year monitoring report demonstrates performance
standards are being met 10% 75%
(85%*)
6 Sixth year monitoring report demonstrates performance
standards are being met 5% 80%
(90%)
7
Seventh year monitoring report demonstrates performance
standards are being met and the project has received closeout
approval
10% 90%
(100%)
*Numbers reported without parenthesis account for the 10% of credits that are withheld until two bankfull events have
occurred. Refer to Section 8.2.
8.1 Initial Allocation of Released Credits
The initial allocation of released credits, as specified in the mitigation plan, can be released by the
NCDMS without prior written approval of the DE upon satisfactory completion of the following
activities:
a. Approval of the Final Mitigation Plan
b. Recordation of the preservation mechanism, as well as a title opinion acceptable to the
USACE covering the property.
c. Completion of project construction (the initial physical and biological improvements to the
mitigation site) pursuant to the mitigation plan; Per the NCDMS instrument, construction
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means that a mitigation site has been constructed in its entirety, to include planting, and
an as-built report has been produced. As-built reports must be sealed by and engineer
prior to project closeout, if appropriate but not prior to the initial allocation of released
credits.
d. Receipt of necessary DA permit authorization or written DA approval for project where DA
permit issuance is not required.
8.2 Subsequent Credit Releases
All subsequent credit releases must be approved by the DE and in consultation with the IRT and are
based on a determination that required performance standards have been achieved. For stream
projects a reserve of 10% of a site’s total stream credits shall be released after two bankfull events
have occurred in separate years, provided the channel is stable and all other performance
standards are met. In the event that less than two bankfull events occur during the monitoring
period, release of these reserve credits shall be at the discretion of the IRT. As projects approach
milestones associated with the credit release, the NCDMS will submit a request for credit release to
the DE along with documentation substantiating achievement of criteria required for release to
occur. This documentation will be included with the annual monitoring report.
9.0 PROJECT SITE MITIGATION PLAN
9.1 Justification for Proposed Intervention
The primary project goals and objectives described in Section 1.0 are focused on improving the
ecological function of the Site including a reduction in sedimentation and fecal coliform
concentrations. The existing conditions assessment demonstrates that the tributaries to UT to
South Fork Cane Creek on-site have been degraded due to livestock access and the removal of
riparian vegetation. The bedforms of the tributaries’ channels are highly degraded due to trampling
by cattle and a fining of bed material from bank erosion and mass wasting of bank material. The
riparian vegetation has been heavily altered along the streambanks. Intervention in the form of
restoration and enhancement is needed to rectify these problems.
9.2 Stream Restoration and Enhancement Design Overview
Wildlands proposes to utilize a restoration approach along UTSF and UT5. Short reaches at the
downstream extent of UT1, UT2, UT3, and UT4 are moderately incised, trampled by cattle, and
exhibit instability in the form of headcuts and unstable banks. These reaches will also be restored
to support the construction stable confluences with the restored UTSF. The restoration activities
being proposed along UT1, UT2, UT3 and UT4 would typically justify a 1:1 ratio. However, these
reaches were initially proposed as enhancement and, for this reason, Widlands proposes a 1.5 to 1
credit ratio. Minimal intervention (Enhancement II) is being proposed along the majority of these
tributary channels (i.e., the upper reaches of UT1, UT2, UT3, and UT4). An Enhancement II
approach will prevent cattle from accessing these tributaries, will support the reestablishment of
functioning stream and riparian ecosystems, and will protect those ecosystems from further
damage. In addition, planting activities will reestablish a thriving riparian buffer. Mitigation
activities are illustrated in the enclosed Figure 9.
9.3 Design Discharge Analysis
Multiple methods (e.g., regional curves, hydraulic geometry relationships, regional flood frequency
analysis, etc.) were used to develop estimates for each of the project restoration reaches of either
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the bankfull discharge or a discharge corresponding to a return interval similar to the theoretical
return interval of the bankfull discharge. The resulting values were compared and concurrence
between the estimates was assessed. The purpose of using multiple methods to estimate bankfull
discharge is to eliminate reliance on a single method as the basis of channel design. However, the
methods commonly produce significantly different results so professional judgement must be used
to select a design discharge. For this analysis the greatest weight was placed on the Wildlands
Flood Frequency Regression equation for the 1.2-yr discharge and the two sets of published
regional curve data. Each of methods used to estimate discharge are described below and the
results are summarized in Table 13 and on Figure 10.
9.3.1 NC Rural Piedmont Regional Curve Predictions
The published NC rural Piedmont Curve (Harman et al., 1999) was used to estimate discharge based
on the drainage area for each design reach.
9.3.2 Provisional Updated NC Piedmont/Mountain Regional Curve Predictions
Design discharges using the draft updated curve for rural Piedmont and mountain streams (Walker,
unpublished) were estimated based on drainage area for each design reach.
9.3.3 Regional Flood Frequency Analysis
Five U.S. Geological Survey (USGS) stream gage sites were identified within reasonable proximity of
the project site for use in development of a project specific regional flood frequency analysis. The
Hosking and Wallis (1993) homogeneity test was performed with a statistics software package to
verify that the gauges selected are appropriate. The gages used were:
USGS 02096740 – Gun Branch near Alamance, NC (DA = 4.06 mi2)
USGS 02096846 – Cane Creek near Orange Grove, NC (DA = 7.54 mi2)
USGS 02097010 – Robeson Creek near Pittsboro, NC (DA = 1.71 mi2)
USGS 02101030 – Falls Creek near Bennett, NC (DA = 3.43 mi2)
USGS 0210166029 – Rocky River at SR1300 near Crutchfield Crossroads, NC (DA = 7.42 mi2)
Flood frequency curves were developed for the 1.2-year and 1.5-year recurrence interval
discharges. These relationships can be used to estimate discharge of those recurrence intervals for
ungauged streams in the same hydrologic region and were solved for discharge with the drainage
area for each project reach as the input.
9.3.4 USGS Flood Frequency Equations for Rural Watersheds in North Carolina
USGS flood frequency equations for rural watersheds in North Carolina (Weaver et al., 2009) were
used to estimate peak discharges for each reach for floods with a recurrence interval of two years.
Table 13, below, shows results for all of the aforementioned methods of calculating a design
discharge as well as the design discharge chosen for each reach.
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Table 13: Summary of Design Bankfull Discharge Analysis
Maney Farm Mitigation Project (unit of measurement is CFS unless otherwise noted)
UTSF-R1 UTSF-R2 UT1C UT2B UT3B UT4B UT5
DA (acres) 115 211 22 11 11 20 76
DA (sq. mi.) 0.18 0.33 0.03 0.02 0.02 0.03 0.12
Wildlands Flood Frequency
Regression Equation Estimates
1-yr event 6 10 2 1 1 1 4
1.2-yr event 22 34 6 4 4 6 16
1.5-yr event 32 50 10 6 6 9 24
1.8-yr event 39 61 12 7 7 11 29
2-yr event 43 67 13 8 8 12 32
Manning's equation results
at surveyed XS
XS1 4.1
XS2 5.7
XS3 4.8
XS4 8.0 7.3
XS5 Pool 12
XS6 Pool 6.9
XS7 7.8 5.5
XS8 11
XS9 6.9
XS10 4.1 9.6
XS11 10 5.4
XS12 Pool 8.9
XS13 11.0
XS14 Pool 9.3
Piedmont Regional Curve Bankfull 26 40 8 5 5 7 19
Alan Walker Curve Bankfull 15 23 4 2 2 4 10
Lowther Curve Bankfull 33 38 21 18 18 21 30
Regional Flood Frequency
Analysis
1.2-yr event 12 18 3 2 2 3 8
1.5-yr event 18 29 5 3 3 5 13
1.8-yr event 24 37 7 4 4 6 17
Final Design Q 19 29 6 3.6 3.5 5.3 14
Note: Units for all discharge estimates are cubic feet per second.
9.4 Design Channel Morphologic Parameters
Design parameters were developed for restoration reaches based on the design bankfull discharge,
dimensionless ratios from the reference reach data, and professional judgment of the designers.
The restoration reaches were designed to be similar to type C streams according to the Rosgen
classification system (Rosgen, 1996). Type C streams are slightly entrenched, meandering streams
with access to the floodplain (entrenchment ratios >2.2), and channel slopes of 2% or less. They
occur within a wide range of valley types and are appropriate for the project landscape. The design
morphological parameters are shown in Table 14.
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Table 14: Design Morphological Parameters
Maney Farm Mitigation Project
Notation Units
UTSF-R1 UTSF-R2 UT1C UT2B UT3B UT4B UT5
Min Max Min Max Min Max Min Max Min Max Min Max Min Max
stream type C C C C C C C
drainage area DA sq mi 0.18 0.33 0.03 0.02 0.02 0.03 0.12
design discharge Q cfs 19.0 29.0 5.6 3.6 3.5 5.3 11.0
bankfull cross-sectional area Abkf SF 6.5 10.2 5.2 1.5 1.5 1.9 4.1
average velocity during bankfull event vbkf fps 3.0 2.8 1.1 3.1 3.3 3.3 2.9
width at bankfull wbkf feet 9.5 12.1 8.1 4.0 4.0 5.0 7.2
maximum depth at bankfull dmax feet 1.0 1.2 1.2 1.5 0.9 1.2 0.5 0.7 0.5 0.7 0.5 0.7 0.8 1.0
mean depth at bankfull dbkf feet 0.7 0.8 0.6 0.4 0.4 0.4 0.6
bankfull width to depth ratio wbkf/dbkf 14.0 14.0 13.0 11 11 13 13.0
depth ratio feet 1.4 1.8 1.4 1.8 1.4 1.8 1.4 1.8 1.4 1.8 1.4 1.8 1.4 1.8
bank height ratio BHR 0.9 1.1 0.9 1.1 0.9 1.1 0.9 1.1 0.9 1.1 0.9 1.1 0.9 1.1
floodprone area width wfpa feet 21 48 27 61 18 41 9 20 9 20 11 25 16 36
entrenchment ratio ER 2.2 5.0 2.2 5.0 2.2 5.0 2.2 5.0 2.2 5.0 2.2 5.0 2.2 5.0
valley slope Svalley feet/ foot 0.0129 0.0114 0.0083 0.0080 0.0170 0.0073 0.0138
channel slope Schnl feet/ foot 0.0092 0.0108 0.0081 0.0095 0.0066 0.0075 0.0064 0.0073 0.0147 0.0167 0.0058 0.0066 0.0099 0.0115
riffle slope Sriffle feet/ foot 0.0120 0.0505 0.0106 0.0447 0.0086 0.0355 0.0083 0.0342 0.0191 0.0786 0.0088 0.0312 0.0128 0.0541
riffle slope ratio Sriffle/Schnl 1.3 4.7 1.3 4.7 1.3 4.7 1.3 4.7 1.3 4.7 1.3 4.7 1.3 4.7
pool slope Sp feet/ foot 0.0000 0.0044 0.0000 0.0029 0.0000 0.0007 0.0000 0.0114 0.0000 0.0126 0.0000 0.0119 0.0000 0.0053
pool slope ratio Sp/Schnl 0.00 0.40 0.00 0.40 0.00 0.40 0.00 0.40 0.00 0.40 0.00 0.40 0.00 0.40
pool-to-pool spacing Lp-p feet 3 67 4 85 2 44 1 24 1 24 2 31 2 44
pool spacing ratio Lp-p/wbkf 0.3 7.0 0.3 7.0 0.3 6.1 0.3 6.1 0.3 6.1 0.3 6.1 0.3 6.1
pool cross-sectional area SF 8.5 13.0 13.3 20.4 6.7 10.4 2.0 3.0 2.0 3.0 2.4 3.8 5.3 8.2
pool area ratio 1.3 2.0 1.3 2.0 1.3 2.0 1.3 2.0 1.3 2.0 1.3 2.0 1.3 2.0
maximum pool depth feet 1.1 2.1 1.3 2.6 0.9 1.8 0.6 1.2 0.6 1.2 0.6 1.2 0.9 1.8
pool depth ratio 1.6 3.1 1.6 3.1 1.6 3.1 1.6 3.1 1.6 3.1 1.6 3.1 1.6 3.1
pool width at bankfull feet 10.5 14.3 13.3 18.2 7.9 10.8 4.4 6.0 4.4 6.0 5.5 7.5 7.9 10.8
pool width ratio 1.1 1.5 1.1 1.5 1.1 1.5 1.1 1.5 1.1 1.5 1.1 1.5 1.1 1.5
Maney Farm Mitigation Project
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Notation Units
UTSF-R1 UTSF-R2 UT1C UT2B UT3B UT4B UT5
Min Max Min Max Min Max Min Max Min Max Min Max Min Max
sinuosity K 1.2 1.4 1.2 1.4 1.1 1.25 1.1 1.25 1.1 1.25 1.1 1.25 1.2 1.4
belt width wblt feet 15 85 19 108 13 72 6 36 6 36 8 45 12 64
meander width ratio wblt/wbkf 1.6 8.9 1.6 8.9 1.6 8.9 1.6 8.9 1.6 8.9 1.6 8.9 1.6 8.9
meander length feet 29 156 36 198 24 133 12 66 12 66 15 82 22 118
meander length ratio 3.0 16.4 3.0 16.4 3.0 16.4 3.0 16.4 3.0 16.4 3.0 16.4 3.0 16.4
radius of curvature Rc feet 17 55 22 70 11 47 5 23 5 23 7 29 13 42
radius of curvature ratio Rc/ wbkf 1.8 5.8 1.8 5.8 1.3 5.8 1.3 5.8 1.3 5.8 1.3 5.8 1.3 5.8
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9.5 Sediment Transport Analysis
Wildlands assessed the watershed and stream channels to gain an understanding of the quantity of
sediment supplied to the design reaches and how this supply has changed over time, and may
change in the future. This was necessary to qualitatively understand the sediment supply for the
design system. In unstable or rapidly changing watersheds or for streams with visual signs of high
bedload supply, a detailed analysis including field data collection and capacity calculations may be
necessary for proper design.
The watershed study, detailed in Sections 4.1 and 4.2, included an assessment of historical land use
changes, an evaluation of existing stream conditions, and a forecast of future land use changes
during the life of the project. The results of this assessment indicate the land use on-site and within
the contributing watershed has been utilized for hay or livestock production since 1972. The
riparian buffer was reduced the prior to 1972 to maximize the area available to agricultural
practices. The land cover patterns and land uses have been consistent for at least the past 40 years
and based on the rural setting of this project the watershed is expected to remain stable for the
foreseeable future. The sediment supply from the contributing watershed upstream of the project
site is expected to remain small and stable. UTSF does shows signs of sediment deposition and
aggradation, (visual observations of sediment accumulation and reported d50 values for the
pavement and sub-pavement samples of less than 2mm). However, this sediment can be largely
attributed to local bank erosion within the project site. Degradation of the project tributaries can
be attributed to cattle trampling and the propagation of head cuts from the main stem. These
observations suggest that the sediment load is predominately contributed by local factors within
the project corridor and the sediment load contributed by the upstream watershed is relatively
low. Restoration activities and cattle exclusion will address the local factors but the watershed
conditions are not anticipated to change drastically due to the rural setting and consistent land use
practices.
9.5.1 Capacity Analysis
Based on the watershed assessment described above, the project streams currently appear to be
supply limited (e.g. have capacity to move a sediment load greater than the supplied load). There is
no reason to believe that the watershed will be altered in the future to increase the sediment yield.
The restoration reaches have been designed to maintain or exceed the capacity of the existing
channels and grade control structures (detailed in Section 9.6) have been utilized to prevent future
incision.
9.5.2 Competence Analysis
In natural streams, the shear stress in a channel increases corresponding to an increase in
discharge until the point at which the stream is flowing full (bankfull) and gains access to the
floodplain. The floodplain access disperses the flow and prevents further increases in shear stress
within the channel. This relationship of shear stress, channel dimension and discharge influences
erosion potential within the channel and the channels ability to transport certain sizes of sediment
(competence). To support the competence analysis, the calculated shear stresses, for both exsiting
and proposed conditions, were compared to determine if the proposed stream will be able to move
the bed material within the channel and to support material sizing within the constructed riffles.
The competence analysis for each project reach is described below and the results are included in
Table 15.
Maney Farm Mitigation Project
Final Mitigation Plan Page 33
Unnamed Tributary to SF (Reach 1)
Sieve analysis results (Appendix 5) of a pavement sample at indicate a d50 of 0.1 and a d85 of 1.7.
The subpavement results for the d50 and d85 were 0.02 mm and 0.46 mm respectively. These
results along with field observations indicate that, as a result of cattle trampling the stream bed,
fine sediment has accumulated and covered the legacy bed material along UTSF Reach 1. The
results of the UTSF Reach 1 shear stress analysis indicate that this reach has the competence to
entrain particles up to 28.9 mm in size, much larger than the current substrate in the channel. This
shear stress creates excess capacity which has contributed to incision that has been noted along
the reach.
Unnamed Tributary to SF (Reach 2)
Results of the sieve analysis for UTSF Reach 2 indicate a pavement layer d50 of 19.0 mm and a d85 of
35.8 mm. The subpavement d50 indicated by the analysis is 5.7 mm and the d85 is 17.2 mm. The
results of the UTSF Reach 2 shear stress analysis indicate that this reach has the competence to
entrain particles up to 34.2 mm in size. This shear stress creates excess capacity which has
contributed to incision along the reach.
Unnamed Tributary 5
Results of the sieve analysis for UT5 suggest a d50 of 15.5 mm and a d85 of 30.8 for the pavement
layer and a d50 of 0.4 mm and a d85 of 7.6 mm for the subpavement. The existing channel shear
stress indicates that UT5 has the competence to entrain particles up to 14 mm. This shear stress
does not indicate excess capacity for this reach and some deposition was observed along this
reach.
Table 15: Sediment Transport Competence Analysis
Maney Farm Mitigation Project
Parameter UTSF-R1 UTSF-R2 UT5
Particle Size from sub-
pavement Sediment
Sample Pavement
Sub-
pavement Pavement
Sub-
pavement Pavement
Sub-
pavement
D50 (mm) 0.1 0.02 19.0 5.7 15.5 0.4
D85 (mm) 1.7 0.5 35.8 17.2 30.9 7.7
Existing Shear Stress
(lb/ft2) 0.39 0.45 0.19
Movable Particle Size
(mm) Shield curve 28.9 34.2 14.0
Proposed Shear Stress
(lb/ft2) 0.42 0.44 0.37
Movable Particle Size
(mm) Shield curve 31.7 33.0 27.5
Sediment Transport Design Considerations
Based on the results of the watershed analysis and the proposed design which will eliminate the
major sediment source (fines from on-side bank erosion and livestock trampling of streams) it is
safe to assume that the design restoration reaches will have enough capacity to move the supplied
sediment load. This assumption is based on the following:
Maney Farm Mitigation Project
Final Mitigation Plan Page 34
The upstream watershed has remained stable for decades and is drained by a network of
small agricultural ditches that do not supply much sediment.
The upstream watershed is rural and landuse is not expected to change in the coming years
or even decades.
The major sediment supply is derived from onsite reaches and this supply will be reduced
due to the restoration.
The system does not appear to have a substantial bedload of coarse material.
Based on this qualitative analysis a threshold channel design is appropriate and no further
monitoring or modeling of bedload supply and transport capacity is warranted.
The results of the competence analysis were utilized to support the design of the restoration
reaches. Based on the data presented in Table 15, the competence of UTSF reaches 1 and 2 will
remain essentially the same. Once the cattle are removed from the streams, the bed material will
coarsen somewhat. However, the channels have the competence to move particles in the coarse
gravel to small cobble size classes so additional aggradation is not expected to occur. Constructed
riffles of coarse material (ranging from cobble to small boulders) and log sills will be used for grade
control to prevent incision. For UT5 the shear stress will increase substantially. Signs of
aggradation of small particle material have been observed in portions of this reach. The increase in
shear stress should be enough to move this material while constructed riffles and log sills will also
be used in this reach for grade control.
In order to mimic the historic conditions and to discourage and /or prevent future incision, native
rock material will be harvested from both the hill slope and the existing channel. Natural bed
material will be harvested along UTSF Reach 2 and UT5 prior to backfilling the existing channel. This
native material will be utilized to construct the proposed riffles along the design reaches, along
with coarser material harvested from the hill slope. The gravel harvested from the hill slope is
expected to fall within the range of 8 to 64 mm with an average d50 size of approximately 36 mm. It
should be noted that, although the upstream sediment supply is not expected to change, fine bed
materials from fluvial erosion and trampling of the banks will be eliminated or reduced after
construction resulting in coarsening of the bed material.
9.6 Project Implementation
9.6.1 Grading and Installation of Structures
UTSF and UT5 reaches will be improved through Priority I restoration techniques. New channels will
be constructed offline with stable meander patterns mimicking natural Piedmont streams, and the
beds of the channels will be raised so that the floodplains are inundated during flow events larger
than the design bankfull discharge. Where necessary, floodplain grading will be conducted to
slightly lower floodplain elevations resulting in a more natural exchange of organic matter and
sediment between the stream and floodplain ecotones. The streambeds will be composed of
alternating riffle-pool sequences to provide habitat and flow diversity. The cross-sectional
dimensions of the channels will be reconstructed as designed with stable side slopes that are
matted and planted with native vegetation for long-term stability. Brush toe built from on-site
materials and sod mats harvested on-site will be used to protect banks and provide aquatic habitat.
Enhancement I techniques will be used on UT1C, UT2B, UT3B, and UT4B. This approach will
enhance bed features and reduce the level of incision of the existing channels and allow these
reaches to be tied into the UTSF Priority I restoration reach.
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UT1A, UT1B, UT2A, UT3A, and UT4A will be improved through Enhancement II techniques.
Treatment for these areas will include replanting the riparian buffer with native tree species,
fencing out livestock, and treatment of any invasive species. There will be no alteration of
floodplain grades or channel dimensions for these sections of stream.
Additionally, streambanks at existing cattle crossings and wallow areas will be reconstructed,
matted with coir fiber matting and planted with live stakes to improve stability and reduce scour.
The entire riparian buffer will be planted with native vegetation, livestock will be fenced out, and
invasive species will be treated.
Instream structures will primarily include constructed riffles and log sills. Several types of
constructed riffles will be utilized in the restoration reaches to establish a varied flow pattern,
habitat, and grade control while providing a source of carbon for nutrient cycling. Native rock of
various sizes (cobble, gravel, and fines) harvested on site will be used as much as possible to create
these types of riffles. Types of riffles proposed for this site include:
Chunky riffles with larger (small boulder and large cobble) rock embedded throughout the
length of the native rock riffle to provide additional habitat as well as grade control for
steeper riffles.
Native material riffles to re-establish a large gravel substrate to the channels.
Woody riffles with brush and logs compacted into the bed of native rock to increase woody
material in the channel.
Rock and Roll riffles to incorporate larger woody debris and meander the thalweg within
longer riffles.
9.6.2 Riparian Planting
As a final stage of construction, riparian buffers of restoration and enhancement reaches will be
seeded and planted with early successional native vegetation chosen to create a Piedmont
Bottomland Forest community. The specific species composition to be planted was selected based
on the community type, observations of the occurrence of species in the existing buffer, and best
professional judgment on species establishment and anticipated site conditions in the early years
following project implementation. Species chosen for the planting plan are listed in Table 16.
The riparian buffer areas will be planted with bare root seedlings. Areas within the riparian zone
which currently support a mature overstory will be enhanced through a supplemental planting of
shade tolerant understory shrub species. In addition, the stream banks will be planted with live
stakes and the channel toe will be planted with plugs. Permanent herbaceous seed will be placed
on stream banks, floodplain areas, and all disturbed areas within the project easement. Proposed
planting zones and the associated species are shown in the construction plan set.
Species planted as bare roots within the open pasture areas will be spaced at an initial density of
605 plants per acre based on 12-ft by 6-ft spacing (targeted densities after monitoring year 3 are
320 woody stems per acre). The supplemental shrub species planting will be spaced at an initial
density of 300 plants per acre based on a 24-ft by 12-ft spacing. Live stakes will be planted on
channel banks at a 2-ft to 3-ft spacing on the outside of meander bends and a 6-ft to 8-ft spacing on
tangent sections.
To help ensure tree growth and survival, soil amendments may be added to areas of floodplain cut.
Soil tests will be performed in areas of cut and fertilizer and lime will be applied based on the
results. Additionally, topsoil will be stockpiled, reapplied, and disked before permanent seeding
and planting activities take place.
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Invasive species within the riparian buffers will be treated and/or removed at the time of
construction. The extent of invasive species coverage will be monitored, mapped and controlled as
necessary throughout the required monitoring period.
Table 16: Planting List
Maney Farm Mitigation Project
Streambank Planting Zone (Live Stakes)
Species Common Name
Salix nigra Black Willow
Cornus ammomum Silky Dogwood
Salix sericea Silky Willow
Physocarpos opulifolius Ninebark
Streambank Planting Zone (Herbaceous Plugs)
Juncus effusus Common Rush
Carex alata Broadwing Sedge
Panicum virgatum Switchgrass
Buffer Planting Zone (Bare Root)
Alnus serrulata Tag Alder
Quercus phellos Willow Oak
Platanus occidentalis Sycamore
Betula nigra River Birch
Aesculus pavia Red Buckeye
Liriodendron tulipifera Tulip Poplar
Quercus palustris Pin Oak
Fraxinus pennsylvanica Green Ash
Carpinus caroliniana American Hornbeam
Viburnum prunifolium Blackhaw Viburnum
Calycanthus floridus Sweetshrub
Callicarpa americana American Beautyberry
Symphoricarpos orbiculatus Coralberry
Permanent Riparian Seeding
Panicum rigidulum Redtop Panicgrass
Agrostis hyemalis Winter Bentgrass
Chasmanthium latifolium River Oats
Rudbeckia hirta Blackeyed Susan
Coreopsis lanceolata Lanceleaf Coreopsis
Carex vulpinoidea Fox Sedge
Panicum clandestinum Deertongue
Elymus virginicus Virginia Wild Rye
Asclepias syrica Common Milkweed
Baptisia australis Blue False Indigo
Gaillardia pulchella Annual Gaillardia
Echinacea purpurea Pale Purple Coneflower
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Final Mitigation Plan Page 37
10.0 MAINTENANCE PLAN
The Site shall be monitored on a regular basis and a physical inspection of the Site shall be
conducted at a minimum of once per year throughout the post-construction monitoring period
until performance standards are met. These site inspections may identify the site components and
features that require routine maintenance. Routine maintenance should be expected most often in
the first two years following site construction and may include the following features listed in Table
17 below.
Table 17: Maintenance Plan
Maney Farm Mitigation Project
Component /
Feature Maintenance Through Project Close-Out
Stream
Routine channel maintenance and repair activities may include chinking of in-stream structures to
prevent piping, securing loose coir matting, and supplemental installations of live stakes and other
target vegetation along the channel. Areas where stormwater and floodplain flows intercept the
channel may also require maintenance to prevent bank failures and head -cutting. Beaver dams that
inundate the streams channels shall be removed and the beaver sh all be trapped.
Vegetation
Vegetation shall be maintained to ensure the health and vigor of the targeted community. Routine
vegetation maintenance and repair activities may include supplemental planting, pruning, mulching,
and fertilizing. Exotic invasive plant species shall be controlled by mechanical and/or chemical
methods. Any vegetation control requiring herbicide application will be performed in accordance
with the NC Department of Agriculture (NCDA) rules and regulations.
Site Boundary
Site boundaries shall be identified in the field to ensure clear distinction between the mitigation site
and adjacent properties. Boundaries may be identified by fence, marker, bollard, post, tree-blazing,
or other means as allowed by site conditions and/or conservation easement. Boundary markers
disturbed, damaged, or destroyed will be repaired and/or replaced on an as -needed basis.
11.0 PERFORMANCE STANDARDS
The stream and buffer performance criteria for the Site will follow approved performance criteria
presented in the DMS Mitigation Plan Template (version 2.2, 06/08/2012), the DMS Monitoring
Requirements and Performance Standards for Stream and/or Wetland Mitigation (11/7/2011), and
the Stream Mitigation Guidelines issued in April 2003 by the USACE and NCDWR. Annual
monitoring and semi-annual site visits will be conducted to assess the condition of the finished
project. The stream restoration and enhancement sections and the buffer restoration sections of
the project will be assigned specific performance criteria components for stream morphology,
hydrology, and vegetation. Performance criteria will be evaluated throughout the seven year post-
construction monitoring. At the conclusion of the fifth monitoring year, Wildlands may propose to
terminate stream and/or vegetation monitoring if all performance criteria have been successfully
met and two bankfull events have occurred during separate years. An outline of the performance
criteria components follows.
11.1 Streams
11.1.1 Dimension
Riffle cross-sections on the restoration reaches should be stable and should show little change in
bankfull area, maximum depth ratio, and width-to-depth ratio. Per DMS guidance, bank height
ratios shall not exceed 1.2 and entrenchment ratios shall be at least 2.2 for restored channels to be
considered stable. Reach riffle cross-section dimension means should fall within the parameters
Maney Farm Mitigation Project
Final Mitigation Plan Page 38
defined for channels of the appropriate Rosgen stream type. If any changes do occur, these
changes will be evaluated to assess whether the stream channel is showing signs of instability.
Indicators of instability include a trend in vertical incision or eroding channel banks over the
monitoring period. Remedial action would not be taken if channel changes indicate a movement
toward stability.
11.1.2 Pattern and Profile
Visual assessments and photo documentation should indicate that streams are remaining stable
and do not indicate a trend toward vertical or lateral instability.
11.1.3 Substrate
Substrate materials in the restoration reaches should indicate a progression towards or the
maintenance of coarser materials in the riffle features and smaller particles in the pool features.
11.1.4 Bankfull Events
Two bankfull flow events must be documented on the restoration reaches within the seven-year
monitoring period. The two bankfull events must occur in separate years. Stream monitoring will
continue until success criteria in the form of two bankfull events in separate years have been
documented.
11.1.5 Photo Documentation
Photographs should illustrate vegetative and morphological stability on an annual basis at the Site.
Cross-section photos should demonstrate no excessive erosion or degradation of the banks.
Longitudinal photos should indicate the absence of persistent bars within the channel or vertical
incision. Grade control structures should remain stable. Deposition of sediment on the bank side of
vane arms is preferable. Maintenance of scour pools on the channel side of vane arms is expected.
11.1.6 Vegetation
The final vegetative success criteria for the stream restoration and enhancement areas will be
based on the planted areas prescribed.
Survival of 210 planted stems per acre in the standard planting zones at the end of the monitoring
period is required. The interim measure of vegetative success within these areas will be the survival
of at least 320 planted stems per acre at the end of the third monitoring year and at least 260
stems per acre at the end of the fifth year of monitoring. Planted trees within the standard planted
zones must average 10 feet in height in each plot at the end of the seventh year of monitoring. If
this performance standard is met by year five and stem density is trending towards success (i.e., no
less than 260 five year old stems/acre), monitoring of vegetation on the Site may be terminated
with written approval by the USACE in consultation with the Interagency Review Team. The extent
of invasive species coverage will also be monitored and controlled as necessary throughout the
required monitoring period. The supplemental planting of shade tolerant understory species will be
monitored to determine survival rates of these species. However, the results will not be tied to
project success and no performance standard is proposed.
11.1.7 Visual Assessment
Visual assessments should support the specific performance standards for each metric as described
above.
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Final Mitigation Plan Page 39
12.0 MONITORING PLAN
Annual monitoring data will be reported using the DMS Monitoring Report Template (version 1.5,
06/08/2012). The monitoring report shall provide project data chronology that will facilitate and
understanding of project status and trends, population of DMS databases for analysis, research
purposes, and assist in decision making regarding close-out. The monitoring period will extend
seven years beyond completion of construction or until performance criteria have been met. All
survey will be tied to grid. Project monitoring requirements in the sections above are described
below and summarized in Table 18 and illustrated in Figure 11.
12.1 Streams
12.1.1 Dimensions
In order to monitor the channel dimension, permanent cross-sections will be installed along riffle
and pool sections according to DMS guidance. Two permanent cross-section will be installed per
1,000 feet of channel along the restored streams. Each cross-section will be permanently marked
with pins to establish its location. Cross-section surveys will include points measured at all breaks in
slope, including top of bank, bankfull, edge of water, and thalweg. Cross-sections will be surveyed
annually for the seven year monitoring period.
12.1.2 Pattern and Profile
The as-built survey will include a longitudinal profile for the baseline monitoring report.
Longitudinal profile surveys will not be conducted during the seven year monitoring period unless
other indicators during the annual monitoring indicate a trend towards vertical and/or lateral
instability. If a longitudinal profile is deemed necessary, monitoring will follow standards as
described in the DMS Monitoring Requirements and Performance Standards for Stream and/or
Wetland Mitigation (11/07/2011) and the 2003 USACE and NCDWR Stream Mitigation Guidance for
the necessary reaches.
12.1.3 Substrate
A reach-wide pebble count will be performed in each restoration and enhancement level I reach
(UTSF-R1, UTSF-R2, UT1C, UT2B, UT3B, UT4B, and UT5) each year for classification purposes. A
pebble count will be performed at each surveyed riffle to characterize the bed material during the
years of the cross-section survey.
12.1.4 Bankfull Events / Gauging
Bankfull events will be documented using a crest gauge and/or pressure transducer, photographs,
and visual assessments such as debris lines. Three gauges will be installed within a riffle section
along UTSF Reaches 1 and 2 and UT5. The crest gauges will be installed within one of the surveyed
riffle cross-sections. The gauges will be checked and/or downloaded at each site visit to determine
if a bankfull event has occurred. Photographs will be used to document occurrences of debris lines
and sediment deposition. An additional gauge with a pressure transducer will be installed within
the intermittent reach of UTSF Reach 1 to record water surface elevations for a minimum of 30
days following the completion of construction activities.
12.1.5 Photo Documentation
Photographs will be taken once a year to visually document stability for seven years following
construction. Permanent markers will be established and located with GPS equipment so that the
Maney Farm Mitigation Project
Final Mitigation Plan Page 40
same locations and view directions on the Site are photographed each year. Photos will be used to
monitor stream restoration and enhancement reaches as well as vegetation plots.
Longitudinal reference photos will be established at the tail of riffles approximately every 200 LF
along the channel by taking a photo looking upstream and downstream. Cross-sectional photos will
be taken of each permanent cross-section looking upstream and downstream. Reference photos
will also be taken for each of the vegetation plots. Representative digital photos of each permanent
photo point, cross-section and vegetation plot will be taken on the same day the stream and
vegetation surveys are conducted. The photographer will make every effort to consistently
maintain the same area in each photo over time.
12.1.6 Vegetation
Vegetation monitoring plots will be installed and evaluated within the restoration and
enhancement areas to measure the survival of the planted trees. The number of monitoring
quadrants required is based on the DMS monitoring guidance document (version 1.4, 11/17/11).
The size of individual quadrants will be 100 square meters for woody tree species and shrubs.
Vegetation monitoring plots will be installed to monitor both the standard planting areas as well as
the supplemental planting zone areas. The number of monitoring plots to be installed in the
planting zones are representative of the area proposed for each treatment type. Vegetation
assessments will be conducted following the Carolina Vegetation Survey (CVS) Level 2 Protocol for
Recording Vegetation (2006).
The initial baseline survey will be conducted within 21 days from completion of site planting and
used for subsequent monitoring year comparisons. The first annual vegetation monitoring activities
will commence at the end of the first growing season, during the month of September. The
restoration and enhancement sites will then be evaluated each subsequent year between June 1
and September 31. Species composition, density, and survival rates will be evaluated on an annual
basis by plot and for the entire Site. Individual plot data will be provided and will include height,
density, vigor, damage (if any), and survival. Planted woody stems will be marked annually as
needed and given a coordinate, based off a known origin, so they can be found in succeeding
monitoring years. Mortality will be determined from the difference between the previous year’s
living planted stems and the current year’s living planted stems.
12.1.7 Visual Assessment
Visual assessments will be performed along all stream and buffer restoration areas on a semi-
annual basis during the seven year monitoring period. Problem areas will be noted such as channel
instability (e.g. lateral and/or vertical instability, in-stream structure failure/instability and/or
piping, headcuts), vegetation health (e.g. low stem density, vegetation mortality, invasive species
or encroachment, beaver activity, or livestock access). Areas of concern will be mapped and
photographed accompanied by a written description in the annual report. Problem areas will be re-
evaluated during each subsequent visual assessment. Should remedial actions be required,
recommendations will be provided in the annual monitoring report.
Maney Farm Mitigation Project
Final Mitigation Plan Page 41
Table 18: Monitoring Requirements.
Maney Farm Mitigation Project
Parameter Monitoring Feature
Quantity/Length by Reach
Frequency Notes UTSF R1 UTSF R2 UT1A UT1B UT1C UT2A UT2B UT3A UT3B UT4A UT4B UT5
Dimension
Riffle Cross-Section 2 2 N/A N/A 1 N/A 1 N/A 1 N/A 1 1
Annual 1
Pool Cross-Section 2 1 N/A N/A 1 N/A 1 N/A 1 N/A 1 1
Pattern Pattern N/A N/A
2
Profile Longitudinal Profile N/A N/A
Substrate
Reach-Wide (RW)
Riffle (RF)
100 Pebble Count
1 RW
2 RF
1 RW
2 RF N/A N/A 1 RW
1 RF N/A 1 RW
1 RF N/A 1 RW
1 RF N/A 1 RW
1 RF
1 RW
1 RF Annual
Hydrology Stream Gauge 1 1 N/A N/A N/A N/A N/A N/A N/A N/A N/A 1 Annual 3
Vegetation Vegetation Plots 14 (11 Standard Planting Zones & 3 Supplemental Planting Zone) Annual
Visual Assessment All Streams Y Bi-annual
Exotic and Nuisance
Vegetation
Annual 4
Project Boundary
Annual 5
Reference Photos Photos 32 Annual 6
Notes:
1. Cross-sections will be permanently marked with rebar to establish location. Surveys will include points measured at all breaks in slope, including top of bank, bankfull, edge of water, and thalweg. The number of cross-sections proposed was established using the small stream guidance
of two per 1,000 feet of stream.
2. Entire profile will be surveyed during the as-built for all project streams.
3. One gauge will be installed along each restoration reach. Devices will be inspected quarterly or semi-annually, evidence of bankfull will be documented with a photo or gauge records.
4. Locations of exotic and nuisance vegetation will be recorded using a GPS and mapped.
5. Locations of fence damage, vegetation damage, boundary encroachments, etc. will be recorded using a GPS and mapped.
6. Markers will be established and recorded using a GPS so that the same locations and view directions on the Site are monitored.
Maney Farm Mitigation Project
Final Mitigation Plan Page 42
13.0 LONG-TERM MANAGEMENT PLAN
The design of UT to South Fork Cane Creek and associated tributaries have been modeled after
natural, functioning, and self-sustaining stable stream systems using natural materials to reinforce
stability. This design approach along with the best available construction methods will provide for
stability while on-site vegetation matures. This approach is intended to promote a self-sustaining
stream system and eliminate the need for long-term management activities. Thus, no long-term
management activities are anticipated for this site. The mitigation site will remain in private
ownership and will be protected with a conservation easement based on the Full Delivery
Conservation Easement model dated July 2011. The State will serve as the Grantee and will be
responsible for inspecting and enforcing the CE following approval of the Final Mitigation Plan.
Upon approval for close-out by the Interagency Review Team (IRT), the Site will be transferred to
the NCDENR Division of Natural Resource Planning and Conservation’s Stewardship Program. This
program currently houses DMS stewardship endowments within the non-reverting, interest-
bearing Conservation Lands Stewardship Endowment Account. The use of funds from the
Endowment Account is governed by North Carolina General Statute GS 113A-232(d)(3). Interest
gained by the endowment fund may be used only for the purpose of stewardship, monitoring,
stewardship administration, and land transaction costs, if applicable. The NCDENR Stewardship
Program intends to manage the account as a non-wasting endowment. Only interest generated
from the endowment funds will be used to steward the compensatory mitigation sites. Interest
funds not used for those purposes will be re-invested in the Endowment Account to offset losses
due to inflation.
14.0 ADAPTIVE MANAGEMENT PLAN
Upon completion of site construction, DMS will implement the post-construction monitoring
protocols previously defined in this document. Project maintenance will be performed as described
previously in this document. If, during the course of annual monitoring it is determined the Site’s
ability to achieve site performance standards are jeopardized, DMS will notify the USACE of the
need to develop a Plan of Corrective Action. The Plan of Corrective Action may be prepared using
in-house technical staff or may require engineering and consulting services. Once the Corrective
Action Plan is prepared and finalized DMS will:
Notify the USACE;
Collaborate with the USACE and the IRT to finalize and secure authorization for the
proposed remedial actions;
Revise performance standards, maintenance requirements, and monitoring requirements
as necessary and/or required by the USACE;
Obtain any permits necessary to implement and complete the identified remedial actions;
and
Implement the Corrective Action Plan and provide the USACE with record drawings that
depict the extent and nature of the work performed.
15.0 FINANCIAL ASSURANCES
Pursuant to Section IV and Appendix III of the Division of Mitigation Services In-Lieu Fee Instrument
dated July 28, 2010, the North Carolina Department of Environment and Natural Resources has
provided the US Army Corps of Engineers Wilmington District with a formal commitment to fund
Maney Farm Mitigation Project
Final Mitigation Plan Page 43
projects to satisfy mitigation requirements assumed by DMS. This commitment provides financial
assurance for all mitigation projects implemented by the program.
Maney Farm Mitigation Project
Final Mitigation Plan Page 44
16.0 REFERENCES
Harman, W.H., G.D. Jennings, J.M. Patteson, D.R. Clinton, L.O. Slate, A.G. Jessup, J.R. Everhart, and
R.E. Smith. 1999. Bankfull Hydraulic Geometry Relationships for North Carolina
Streams. AWRA Wildland Hydrology Symposium Proceedings. Edited By: D.S. Olsen and
J.P. Potyondy. AWRA Summer Symposium. Bozeman, MT.
North Carolina Center for Geographic Information and Analysis (NC CGIA). 2001. Landcover GIS
layer. Accessed online at: http://data.nconemap.com/geoportal/catalog/main/home.page
North Carolina Division of Water Resources (NCDWR). Surface Water Classifications. Accessed
online at: http://portal.ncdenr.org/web/wq/ps/csu/classifications
North Carolina Department of Environment and Natural Resources. 2005. Division of Water Quality
(NCDWR). Cape Fear River Basinwide Water Quality Plan. Accessed online at:
http://portal.ncdenr.org/c/document_library/get_file?uuid=2eddbd59-b382-4b58-97ed-
c4049bf4e8e4&groupId=38364
North Carolina Division of Mitigation Services (DMS). Mitigation Plan Template Version 2.2,
06/08/2012. Accessed online at:
http://portal.ncdenr.org/c/document_library/get_file?p_l_id=1169848&folderId=7135626&na
me=DLFE-53020.pdf
North Carolina Division of Mitigation Services (DMS). Monitoring Report Template Version 1.5,
06/08/2012. Accessed online at:
http://portal.ncdenr.org/c/document_library/get_file?p_l_id=1169848&folderId=7135626&na
me=DLFE-53021.pdf
North Carolina Division of Mitigation Services (DMS). Monitoring Requirements and Performance
Standards for Stream and/or Wetland Mitigation (11/7/2011). Accessed online at:
http://portal.ncdenr.org/c/document_library/get_file?p_l_id=1169848&folderId=2288101&na
me=DLFE-39234.pdf
North Carolina Division of Mitigation Services (DMS). 2009. Cape Fear River Basin Restoration
Priorities. Accessed online at:
http://www.nceep.net/services/lwps/cape_fear/RBRP%20Cape%20Fear%202008.pdf
North Carolina Geological Survey (NCGS), 1985. Geologic map of North Carolina 1:500,000 scale.
Compiled by Philip M. Brown at el. Raleigh, NC, NCGS.
North Carolina Natural Heritage Program (NHP). 2009. Natural Heritage Element Occurrence
Database, Chatham County, NC. Accessed online at: http://ww.ncnhp.org/web/nhp/database-
search
North Carolina Wildlife Resources Commission. 2005. Wildlife Action Plan. Accessed online at:
http://www.ncwildlife.org/portals/0/Conserving/documents/ActionPlan/WAP_complete.pdf
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