HomeMy WebLinkAboutEast Mingo Mitigation Plan-monitoring updates
FINAL MITIGATION PLAN
Submitted to IRT
June 12, 2023
WILDLANDS CAPE FEAR 06 UMBRELLA
MITIGATION BANK
Site Name: East Mingo Creek Mitigation Site
Johnston County, NC
Cape Fear River Basin
HUC 03030006
USACE Action ID No. SAW‐2020‐02093
NCDWR # 20201989
PREPARED BY:
Wildlands Engineering, Inc.
312 W Millbrook Road, Suite 225
Raleigh, NC 27609
Phone: (919) 851‐9986
Final Mitigation Plan
Wildlands Cape Fear 06 Umbrella Mitigation Bank
East Mingo Creek Mitigation Site
Johnston County, NC
Cape Fear River Basin
HUC 03030006
USACE Action ID No. SAW‐2020‐02093
NCDWR # 20201989
PREPARED BY:
Wildlands Engineering, Inc.
312 W Millbrook Road, Suite 225
Raleigh, NC 27609
Phone: (919) 851‐9986
Contributing Staff:
Angela Allen, PE, Project Manager
John Hutton, Principal in Charge
Charlie Neaves, Lead Scientist, Wetland Delineation
Greg Turner, PE, Project Engineer
Noyes Harrigan, EI, Designer
Catherine Warner, Plan Production
Andrea Thompson, Lead Steward
Jeff Keaton, PE, Lead Quality Assurance
Nicole Macaluso Millns, PE, CFM, Quality Assurance
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TABLE OF CONTENTS
1.0 Introduction .............................................................................................................................. 1
2.0 Basin Characterization and Site Selection .................................................................................. 1
3.0 Baseline and Existing Conditions ............................................................................................... 2
3.1 Watershed Conditions .................................................................................................................. 2
3.2 Landscape Characteristics ............................................................................................................ 2
3.3 Project Resources ......................................................................................................................... 3
3.4 Overall Functional Uplift Potential ............................................................................................. 12
3.5 Site Constraints to Functional Uplift ........................................................................................... 13
4.0 Regulatory Considerations ...................................................................................................... 13
4.1 401/404 ...................................................................................................................................... 14
4.2 Threatened and Endangered Species ......................................................................................... 15
4.3 Cultural Resources / Conservation Lands / Natural Heritage Areas ........................................... 15
4.4 FEMA Floodplain Compliance and Hydrologic Trespass ............................................................. 16
5.0 Mitigation Site Goals and Objectives ....................................................................................... 16
6.0 Design Approach and Mitigation Work Plan ............................................................................ 17
6.1 Design Approach Overview ........................................................................................................ 17
6.2 Reference Streams ...................................................................................................................... 18
6.3 Reference Wetland and Vegetation ........................................................................................... 19
6.4 Design Channel Morphological Parameters ............................................................................... 20
6.5 Design Bankfull Discharge Analysis ............................................................................................ 24
6.6 Sediment Transport Analysis ...................................................................................................... 25
6.7 Project Implementation .............................................................................................................. 26
6.8 Vegetation, Planting Plan, and Land Management .................................................................... 28
6.9 Project Risk and Uncertainties .................................................................................................... 31
7.0 Determination of Credits ......................................................................................................... 31
8.0 Performance Standards ........................................................................................................... 34
9.0 Monitoring Plan ...................................................................................................................... 36
10.0 Long‐Term Management Plan ................................................................................................. 37
Ownership and Long‐Term Manager .......................................................................................... 37
Long‐Term Management Activities ............................................................................................ 37
Funding Mechanism ................................................................................................................... 38
Contingency Plan ........................................................................................................................ 39
11.0 Adaptive Management Plan .................................................................................................... 39
12.0 Financial Assurances ............................................................................................................... 40
13.0 References .............................................................................................................................. 42
TABLES
Table 1: Project Attribute Table Part 1 ................................................................................................. 1
Table 2: Project Attribute Table Part 2 ................................................................................................. 2
Table 3: Summary of Stream Resources ............................................................................................... 7
Table 4: Existing Wetlands Summary .................................................................................................... 8
Table 5: 2022 Groundwater Gauge Summary ..................................................................................... 12
Table 6: Project Attribute Table Part 3 ............................................................................................... 13
Table 7: Estimated Impacts to Project Wetlands ................................................................................ 14
Table 8: Mitigation Goals and Objectives ........................................................................................... 17
Table 9: Functional Impairments and Restoration Approach .............................................................. 18
Table 10: Stream Reference Data Used in Development of Design Parameters ................................... 19
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Table 11: Reference Wetland Hydrology Results 2006‐2010 ............................................................... 20
Table 12: Summary of Morphological Parameters for East Mingo Creek ............................................. 21
Table 13: Summary of Morphological Parameters for Beaver Creek, Cricket Creek, and Deer Creek ... 22
Table 14: Summary of Morphological Parameters for Lamb Creek, Lizard Creek, and Mouse Creek .... 23
Table 15: Summary of Morphological Parameters for Rabbit Creek, Snake Creek, and UT to Beaver
Creek 24
Table 16: Summary of Design Discharge Analysis ............................................................................... 25
Table 17: Results of Competence Analysis .......................................................................................... 26
Table 18: Project Assets and Credits ................................................................................................... 32
Table 19: Summary of Performance Standards ................................................................................... 35
Table 20: Monitoring Components ..................................................................................................... 36
Table 21: Long‐Term Management ..................................................................................................... 38
Table 22: Management Funding ......................................................................................................... 39
Table 23: Financial Assurances Table .................................................................................................. 41
FIGURES
Figure 1 Vicinity Map
Figure 2 Service Area Map
Figure 3 Existing Conditions Map
Figure 4 NCDOT Draft STIP FY 2020‐2029
Figure 5 Watershed Map
Figure 6 USGS Topographic Map
Figure 7 Soils Map
Figure 8 Concept Design Map
Figure 9 Reference Reach Map
Figure 10 Design Discharge Analysis
Figure 11 Monitoring Components Map
APPENDICES
Appendix 1 Maps, Data, and Analysis
Appendix 2 JD Concurrence
Appendix 3 DWR Stream ID, NCSAM, and NCWAM Forms
Appendix 4 Regulatory Correspondence
Appendix 5 Maintenance Plan
Appendix 6 Credit Release Schedule
Appendix 7 Site Protection Instrument
Appendix 8 Financial Assurance
Appendix 9 Draft Plan Sheets
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1.0 Introduction
Wildlands Holdings VI, LLC (“Sponsor”) proposes to develop the East Mingo Mitigation Site (Site) as the
first project under the Wildlands Cape Fear 06 Umbrella Mitigation Bank (“Bank”). Wildlands Holdings
VI, LLC is wholly owned by Wildlands Engineering, Inc.
The Site is in southwest Johnston County, NC approximately two miles northwest of Benson (Figure 1).
The project is the 14‐digit Hydrologic Unit Code (HUC) 03030006020010 and the NC Department of
Environmental Quality Division of Water Resources (NCDEQ DWR) Subbasin 03‐06‐18. The Site will
provide stream and wetland mitigation credits in the Cape Fear Hydrologic Unit 03030006 (Cape Fear
06) (Figure 2). The project involves the restoration and enhancement of East Mingo Creek and its
tributaries to provide 7066.076 stream credits. It also involves the reestablishment, rehabilitation, and
enhancement of wetlands to provide 22.537 riparian wetland credits. The Site will be protected by a
45.89‐acre conservation easement.
Table 1: Project Attribute Table Part 1
Project Information
Project Name East Mingo Mitigation Site
County Johnston
Project Area (acres) 45.89
Project Coordinates (latitude and longitude) 35.398681 N, 78.574376 W
Planted Acreage (acres of woody stems planted) 31.52
2.0 Basin Characterization and Site Selection
The Site is located in the Cape Fear 06 basin. The Cape Fear 06 basin, as described in the DWR 2005
Cape Fear River Basin Water Quality Plan (WQP), includes the municipalities of Clinton, Benson, Coats,
Dunn, Angier, Autryville, Garland, Falcon, Roseboro, and Stedman but is largely forested or in
agricultural use. Several highways bisect the basin including US‐701, NC‐24, NC‐242, US‐13, US‐421, NC‐
27 and I‐95. State highway NC‐210 runs most of the length of the subbasin along the South River.
Developing a mitigation bank will allow unavoidable impacts to Waters of the United States within the
service area (Figure 4) to be mitigated appropriately and provide a means for the economic growth of
this region to continue while ensuring aquatic resources and water quality are maintained. This includes
the potential widening for the aforementioned roads within the watershed.
The proposed Bank is located in DWR subbasin 03‐06‐18 and HUC 03030006020010. There are no
current local or state watershed plans associated specifically with this subbasin. The watershed is
dominated by forest (56%) and agriculture (41%) with urban areas making up less than 2%. There are
over 100 registered swine operations in this subbasin. This subbasin is not included in North Carolina
Division of Mitigation Services’ (DMS) River Basin Restoration Priorities plan for the Cape Fear 06, which
concentrates on the South River and Great Coharie Creek. While DWR devotes a chapter in the Cape
Fear River Basin Plan to the 03‐06‐18, the chapter is focused on the Black River and South River. Visual
inspections indicate the primary stressors in the East Mingo Creek watershed are animal operations,
primarily cattle. The Site addresses degradation due to animal operations by removing livestock from
the Site streams and wetlands, converting agricultural land to forest, and protecting the site from
developmental pressures through the establishment of a conservation easement.
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3.0 Baseline and Existing Conditions
3.1 Watershed Conditions
The Site watershed (Table 2 and Figure 5) is situated in rural Johnston County near Benson, NC. The Site
topography, as indicated on the Benson, NC USGS 7.5‐minute topographic quadrangle, shows a wide,
flat valley bottom spanning most of the Site (Figure 6). Drainage areas for the project reaches were
delineated using 2‐foot contour intervals derived from the North Carolina Floodplain Mapping
Program’s 2007 Light Detection and Ranging (LiDAR) data. Land uses draining to the project reaches are
a mix of forested and agricultural/pasture/hay fields with some residential development and open
water. The land use was calculated using the National Land Cover Database (NLCD) for 2011. The
impervious area within the project catchment at the downstream end was calculated to be less than one
percent of the project catchment using USGS North Carolina StreamStats Version 4.
A review of historic aerials (Appendix 1) from 1950 to 2016 shows the southern half of the site was
cleared between 1964 and 1972 This involved draining an old mill pond and ditching and straightening
East Mingo Creek and several of its tributaries (according to landowner recollection). During this time a
Confined Animal Feeding Operation (CAFO) was installed in the Snake Creek watershed west of the
project site. Between 1974 and 1983 agricultural ponds were added to the headwaters of Cow Creek
and Mouse Creek upstream of the project areas. A pond was added adjacent to Snake Creek upstream
of the project area between 1983 and 1993. Little change was noted in land use or riparian buffer
extents in the watershed since 1993 and riparian buffers within the site have remained consistent since
1972.
The project parcels, and several surrounding parcels are located in a Voluntary Agricultural District
according to Johnston County zoning maps. There are currently no developmental pressures to suggest
future changes in land use that might alter the watershed and/or add stressors throughout the
implementation, monitoring, and closeout of the project.
Table 2: Project Attribute Table Part 2
Project Watershed Summary Information
Physiographic Province Coastal Plain
Ecoregion Rolling Coastal Plain
River Basin Cape Fear 06
USGS HUC (8‐digit, 14 digit) 03030006, 03030006020010
NCDWR Sub‐basin 03‐06‐18
Project Drainage Area (acres) 2,112
Project Drainage Area Percentage of Impervious Area <1%
CGIA Land Use Classification
63% agriculture, 9% forest, 5% urban, 2%
grassland/herbaceous, 11% shrubland, 9% wetland,
1% open water
3.2 Geology and Soils
According to the NC Geologic Survey, the Site is in the Middendorf formation of the Coastal Plain
physiographic province. The Coastal Plain is characterized by relatively flat terraces of primarily
unconsolidated sediments and carbonate rocks ranging in age from Cretaceous to Quaternary. These
layered materials accumulated as sediments deposited in what was once a shallow ocean or shelf
interface along a shallow ocean. The deposits form roughly parallel belts that trend southwest to
northeast. The site is in the belt called the Middendorf Formation (km), which formed during the
Cretaceous period. Sohl and Owens (1991) describe the Middendorf formation as deeply weathered and
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consisting mainly of layered delta plain to fluvial deposits. Sediments are layered in thick black clay and
light‐colored sand layers consisting of sand, sandstone, and mudstone. Sands are primarily quartz;
however, outcrops of feldspar may be up to 15 percent. The majority of the site consists of Bibb sandy
loam soils (Figure 7), which are deep and poorly drained. Grantham silt loams, which are also deep and
poorly drained, are found at the upstream ends of Deer Creek and Lamb Creek. Gilead sandy loam, a
deep and moderately well drained soil, is found at the upstream ends of Wolf Creek, Beaver Creek, and
Lamb Creek. A small area of Uchee loamy coarse sand, a deep well drained soil, is found at the valley
edge on the upstream end of Cow Creek. No exposed bedrock is located on site and there is no geologic
grade control. Grade control features will need to be designed with logs and woody debris to mimic
what would be found in reference streams in similar geologic conditions.
3.3 Project Resources
The southern half of the site is currently maintained for livestock pasture. A forest dominated by
Chinese privet (Ligustrum sinense) is present on the northern half of the site. On March 16, 2020, all Site
streams were evaluated and scored. Stream forms are included in the appendix and further descriptions
of each stream are in Table 3 and Section 3.3.1 below.
3.3.1 Existing Streams
East Mingo Creek and W. Fork East Mingo Creek
East Mingo Creek (DA 2,154 acres)is a perennial sandbed
system that flows south from where the stream enters the site
under Banner Elk Road. At the usptream property boundary,
East Mingo flows through forest and is moderately incised with
a bank height ratio (BHR) of 1.4 (XS1). East Mingo drops over a
headcut near its confluence with Deer Creek and the BHR
increases to 2.1 (XS2). As the stream enters the pasture, the
BHR lowers to a 1.9 (XS3) and then eventually a 1.0 (XS4) at the
downstream end of the project. The upstream wooded reach
appears historically straightened in some areas and has
developed an unstable meander pattern in others, as
evidenced by streambank scour.
An old ditch branches off of East Mingo Creek at the top of the project and parallels the channel on the
right floodplain within the woods. The right floodplain channel appears to have been excavated as a
ditch between 1964 and 1972. The ditch breaks up and re‐forms at a headcut and becomes a
jurisdictional channel paralelling East Mingo Creek in the same valley. This has been named W. Fork East
Mingo Creek.
Bedform diversity and large woody debris are present in the upstream wooded reach, however as East
Mingo enters the pasture, bedform diversity decreases. Within the pasture, channel substrate is
dominated by fines from livestock trampling of the streambed and banks. Historic channel incision is
masked at the downstream portion of East Mingo Creek (below Wolf Creek) because of the influence of
beaver dams downstream of the property holding a higher water elevation within the channel.
East Mingo Creek
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Lizard Creek
Lizard Creek (DA 32 acres) is an intermittent sandbed stream with
low width to depth ratio, flowing through an unconfined, forested
floodplain dominated by Chinese privet. The channel bedform is
highly influenced by root systems of trees and Chinese privet on
the banks, forming instream drop structures and scour pools.
Large woody debris and leaf packs are present. At the
downstream end, Lizard Creek incises to meet the invert elevation
of East Mingo Creek. Bedform is diminished or absent entirely
within the incised area.
Cricket Creek
Cricket Creek (DA 1.7 acres) is a short, intermittent stream that
begins at a headwater wetland and flows west northwesterly into
East Mingo Creek. The channel becomes deeply incised as it
approaches East Mingo Creek. The bedform of Cricket Creek is
largely defined by roots of trees from the forested floodplain.
Snake Creek and Snake Creek Anabranch
Snake Creek (DA 185 acres) is a perennial stream. Upstream of the
site, Snake Creek follows along the western edge of an existing
pond. While the stream is incised, it is not currently threatening
the stability of the pond. Snake Creek enters the site as a single
thread channel. The channel meanders through the wide alluvial
floodplain of East Mingo Creek and splits into Snake Creek and
Snake Creek Anabranch (intermittent). The stream banks and bed
have been severely trampled by livestock. This has caused a fining
of bed material along with lack of bedform. There is an ephemeral
channel that joins Snake Creek coming from the outlet of the
offsite pond. There is no understory in this portion of the woods
due to livestock grazing. Snake Creek and Snake Creek Anabranch
incise in order to meet the elevation of East Mingo Creek.
Snake Creek
Snake Creek Anabranch
Cricket Creek
Lizard Creek
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Deer Creek
Deer Creek (DA 20 acres) is an intermittent stream similar in
function and livestock impact to Snake Creek. There is stable
pattern, and the stream is connected to the floodplain; however,
the banks and bed suffer from extensive livestock trampling. The
upstream end is less trampled due to a dense colony of Chinese
privet on the stream banks and floodplain. Deer Creek incises to
join East Mingo Creek downstream, losing bedform diversity and
floodplain connection in Reach 2.
Mouse Creek
Mouse Creek (DA 9.4
acres) is an intermittent stream that flows through a heavily
grazed wooded pasture. Though incised, it appears vertically
and laterally stable until the confluence of East Mingo Creek
where it incises further. Livestock trampling is evident within
Mouse Creek resulting in a fining of bed material and a lack of
bedform diversity. There is also little to no large woody debris
(LWD) present.
Rabbit Creek and UT to Rabbit Creek
Rabbit Creek (DA 34 acres) is an intermittent stream that flows
through a wooded pasture similar to Mouse Creek. The stream
is stable with good bedform diversity and floodplain access.
Downstream of the wooded buffer, Rabbit Creek appears to
have been historically ditched to drain straight out to East
Mingo Creek. Rabbit Creek’s width to depth ratio increases and
the channel incises, separating it from the floodplain. The
stream bedform and streambanks are extensively impacted by
livestock trampling in this ditched section.
UT to Rabbit Creek (DA 1.3 acres) is short intermittent stream that connects to Rabbit Creek.
Wolf Creek
Wolf Creek (DA 14 acres) is an intermittent stream that lacks a
wooded riparian buffer and is dominated by common rush (Juncus
effuses) and pasture grasses. The channel is overly wide due to
livestock trampling; however, a smaller, nested channel has begun
to form within the larger channel. Wolf Creek has poor bedform
diversity and few instances of LWD.
Mouse Creek
Wolf Creek
Rabbit Creek
Deer Creek
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Lamb Creek
Lamb Creek (DA 14 acres) is a perennial stream that begins at a
headwater wetland seep in a wooded pasture. The channel
transitions between a single thread and multi‐thread channel
influenced by slope changes within the valley. The stream
dimension and pattern appear stable, and stream bedform is
shaped by woody debris and tree roots. As Lamb Creeks enters the
open pasture, the channel becomes single‐thread and the stream
appears to have been historically ditched straight out to East
Mingo Creek. It flows through the riparian wetlands of East Mingo Creek and common rush dominates
the streambanks. Stream bed and banks are so extensively trampled by livestock in the pasture that
they are indiscernible in some areas.
Cow Creek
Cow Creek (DA 16 acres) is an intermittent stream that is impounded by a series of inline farm ponds
upstream of the Bank. Cow Creek enters the Site immediately downstream of a pond outlet and flows
through loblolly pines (Pinus taeda). The stream has good bedform diversity in the pines and limited
LWD. As Cow Creek enters the floodplain of East Mingo Creek the channel flattens, is lined with
common rush, and is trampled by livestock.
Beaver Creek and UT to Beaver Creek
Beaver Creek (DA 12 acres) is an intermittent stream that is impounded by a farm pond at the upstream
extent. The dam has failed, and Beaver Creek is incised through the dam. Beaver Creek remains incised
until it reaches the floodplain wetlands of East Mingo Creek. Beaver Creek consistently lacks bedform
diversity, LWD, and has poor hydrologic connection to the floodplain.
UT to Beaver Creek (DA 0.5 acres) is a small, steep intermittent stream that drains an old sediment pond
(now a wetland) near Benson‐Hardee Road.
Beaver Creek UT to Beaver Creek Cow Creek
Lamb Creek
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Table 3: Summary of Stream Resources
Reach Summary Information
Parameter East Mingo
Creek Beaver Creek Cricket Creek Cow Creek Deer Creek
Length of Reach (lf) 4927 347 77 306 442
Valley Confinement (confined,
moderately confined,
unconfined)
Unconfined Moderately
confined Unconfined Unconfined Unconfined
Drainage Area (acres) 2,154 12 1.7 16 20
Perennial, Intermittent,
Ephemeral Perennial Intermittent Intermittent Intermittent Intermittent
NCDWR Water Quality
Classification C; SW N/A N/A N/A N/A
Stream Classification (Existing
and Proposed) F5, C5 E5b, C5 E5b, C5 E5, N/A C5b, C5
FEMA Classification Zone AE Zone AE
(fringe)
Zone AE
(fringe)
Zone AE
(fringe)
Zone AE
(fringe)
NCSAM Overall Score Low Low Low Low Low
Parameter Lamb Creek Lizard Creek Mouse
Creek Rabbit Creek Snake Creek
Length of Reach (lf) 703 170 421 446 400
Valley Confinement (confined,
moderately confined,
unconfined)
Unconfined Unconfined Unconfined Unconfined Unconfined
Drainage Area (acres) 14 32 9.4 34 185
Perennial, Intermittent,
Ephemeral Perennial Intermittent Intermittent Intermittent Perennial
NCDWR Water Quality
Classification N/A N/A N/A N/A N/A
Stream Classification (Existing
and Proposed) E5, C5 E5b, C5 E5, C5 C5, C5 E5, C5
FEMA Classification Zone AE
(fringe)
Zone AE
(fringe)
Zone AE
(fringe)
Zone AE
(fringe)
Zone AE
(fringe)
NCSAM Overall Score Low Low Low Low Low
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Parameter Snake Creek
Anabranch
UT to Beaver
Creek
UT to Rabbit
Creek Wolf Creek
Length of Reach (lf) 467 94 28 418
Valley Confinement (confined,
moderately confined,
unconfined)
Unconfined Moderately
confined Unconfined Unconfined
Drainage Area (acres) ‐ 0.5 1.3 14
Perennial, Intermittent,
Ephemeral Intermittent Intermittent Intermittent Intermittent
NCDWR Water Quality
Classification N/A N/A N/A N/A
Stream Classification (Existing
and Proposed) C5b C5b, B5 N/A C5, N/A
FEMA Classification Zone AE (fringe) Zone X Zone AE (fringe) Zone AE (fringe)
NCSAM Overall Score ‐ ‐ ‐ Low
3.3.2 Existing Wetlands
Wildlands investigated the extent of Waters of the United States within the project area during the fall
of 2021 and spring of 2022. All jurisdictional resources were located by sub‐meter GPS or conventional
survey. USACE staff provided email concurrence with jurisdictional resource mapping on July 11, 2022.
Existing wetland summary information is presented in Table 4.
Table 4: Existing Wetlands Summary
Wetland Summary Information
Parameter Wetland A Wetland B Wetland C Wetland D
Size of Wetland (acres) 1.380 0.156 1.248 0.041
Wetland Type (NCWAM
Class)
Bottomland
Hardwood Forest
Bottomland
Hardwood Forest
Bottomland
Hardwood Forest
Bottomland
Hardwood Forest
Overall NCWAM Rating Medium Medium Low Medium
Mapped Soil Series Bibb Bibb Bibb Bibb
Drainage Class PD PD PD PD
Soil Hydric Status Yes Yes Yes Yes
Source of Hydrology Groundwater Groundwater Groundwater Groundwater
Restoration or
enhancement method
(hydrologic, vegetative,
etc.)
Hydrologic,
Vegetative
Hydrologic,
Vegetative
Hydrologic,
Vegetative
Hydrologic,
Vegetative
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Wetland Summary Information
Parameter Wetland E Wetland F Wetland G Wetland H
Size of Wetland (acres) 0.033 0.679 1.391 0.497
Wetland Type (NCWAM
Class)
Bottomland
Hardwood Forest
Bottomland
Hardwood Forest
Bottomland
Hardwood Forest
Bottomland
Hardwood Forest
Overall NCWAM Rating Low Low Medium Low
Mapped Soil Series Bibb Bibb Gilead/Grantham Grantham
Drainage Class PD PD MWD/PD PD
Soil Hydric Status Yes Yes No/Yes Yes
Source of Hydrology Groundwater Groundwater Groundwater Groundwater
Restoration or
enhancement method
(hydrologic, vegetative,
etc.)
Hydrologic,
Vegetative
Hydrologic,
Vegetative
Hydrologic,
Vegetative
Hydrologic,
Vegetative
Wetland Summary Information
Parameter Wetland I Wetland J Wetland K Wetland L
Size of Wetland (acres) 0.382 0.011 0.726 0.524
Wetland Type (NCWAM
Class)
Bottomland
Hardwood Forest
Bottomland
Hardwood Forest
Bottomland
Hardwood Forest
Bottomland
Hardwood Forest
Overall NCWAM Rating Low Low Low Low
Mapped Soil Series Bibb Bibb Bibb Bibb
Drainage Class PD PD PD PD
Soil Hydric Status Yes Yes Yes Yes
Source of Hydrology Groundwater Groundwater Groundwater Groundwater
Restoration or
enhancement method
(hydrologic, vegetative,
etc.)
Hydrologic,
Vegetative
Hydrologic,
Vegetative
Hydrologic,
Vegetative
Hydrologic,
Vegetative
Wetland Summary Information
Parameter Wetland M Wetland N Wetland O Wetland P
Size of Wetland (acres) 1.287 0.165 0.109 0.456
Wetland Type (NCWAM
Class)
Headwater
Forest Headwater Forest Bottomland
Hardwood Forest Headwater Forest
Overall NCWAM Rating Low Low Low Medium
Mapped Soil Series Bibb/Gilead Bibb/Uchee Bibb Bibb
Drainage Class PD/MWD PD/WD PD PD
Soil Hydric Status Yes/No Yes/No Yes Yes
Source of Hydrology Groundwater Groundwater Groundwater Groundwater
Restoration or
enhancement method
(hydrologic, vegetative,
etc.)
Vegetative Vegetative Hydrologic,
Vegetative Vegetative
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Wetland Summary Information
Parameter Wetland Q Wetland R Wetland S Wetland T
Size of Wetland (acres) 0.008 0.025 0.022 0.020
Wetland Type (NCWAM
Class)
Bottomland
Hardwood Forest
Bottomland
Hardwood Forest
Bottomland
Hardwood Forest
Bottomland
Hardwood Forest
Overall NCWAM Rating Low Low Low Low
Mapped Soil Series Bibb Bibb Bibb Bibb
Drainage Class PD PD PD PD
Soil Hydric Status Yes Yes Yes Yes
Source of Hydrology Groundwater Groundwater Groundwater Groundwater
Restoration or
enhancement method
(hydrologic, vegetative,
etc.)
Hydrologic,
Vegetative
Hydrologic,
Vegetative
Hydrologic,
Vegetative
Hydrologic,
Vegetative
Wetland Summary Information
Parameter Wetland U Wetland V Wetland W
Size of Wetland (acres) 4.879 4.372 0.655
Wetland Type (NCWAM
Class)
Bottomland
Hardwood Forest
Bottomland
Hardwood Forest Headwater Forest
Overall NCWAM Rating Low Low Low
Mapped Soil Series Bibb Bibb Gilead
Drainage Class PD PD MWD
Soil Hydric Status Yes Yes No
Source of Hydrology Groundwater Groundwater Groundwater
Restoration or
enhancement method
(hydrologic, vegetative,
etc.)
Vegetative Vegetative Hydrologic,
Vegetative
Wetlands were classified and evaluated using the North Carolina Wetland Assessment Method
(NCWAM). Wetlands within the conservation easement were classified as Bottomland Hardwood
Forests or Headwater Forests; the distinguishing factor between these two wetland types is order of the
most closely associated stream channel. Wetland impairments throughout the site are due to
manipulation of the vegetation community, presence of livestock, ditching, and altered hydrology from
stream incision.
The approximate northern third of the project area where Wetland A – Wetland E is located is forested
but contains dense Chinese privet in the understory which is outcompeting native lower strata
vegetation. Livestock does not access this area. East Mingo Creek is incised and generally straight
through this area and presumably drains historic wetlands and partially drains current, existing
wetlands. Based on the 1972 and 1983 historical aerial photos (Appendix 1) and the presence of spoil
piles, it appears a man‐made shallow ditch was constructed along the right toe of slope through part of
this area to divert groundwater discharge down valley instead of across the floodplain. This feature
generally follows the western edge of Wetland C (Figure 3). Although it has been unmaintained for
decades, it still functions to intercept groundwater discharge and partially dry out the right floodplain of
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East Mingo Creek in the vicinity of Wetland C. Moving north to south, the defined flow path of this ditch
terminates. During the wet season or flood events, water splays out overland for a short distance
through Wetland C before entering a network of erosional channels. Given the pattern of these
channels, it is unlikely they were directly manmade, but likely formed as a result of increased
headcutting and erosion rates due to some type of disturbance. These channels were determined to be
non‐jurisdictional features but function to lower in water table in their vicinity.
The middle third of the project area containing Wetland F – Wetland K is accessed by cattle and has a
forested canopy with desirable species composition but has minimal lower strata vegetation present
due to livestock impacts. East Mingo Creek and the West Fork of East Mingo Creek are incised and have
a partial drainage effect on wetlands within the floodplain. Parts of Wetland F, Wetland G, and Wetland
H have developed erosional features that directly drain groundwater discharge to East Mingo Creek.
The Southern third of the project area is maintained as pasture and regularly grazed by livestock. All
wetlands within this area (Wetland N – Wetland W) provide poor habitat quality and minimal water
quality improvements. Hydrologic regime of wetlands in this area varies with differences in persistence
of groundwater discharge and proximity to an incised stream channel. Wetland L, Wetland O, Wetland
Q, Wetland S, and Wetland T are partially drained by the incised East Mingo Creek channel. Wetland N,
Wetland P, the pasture portion of Wetland M, Wetland U, and Wetland V, do not appear affected by any
major drainage conduit. Wetland P, Wetland U, and Wetland V each contain portions that appear to be
ponded or saturated at the soil surface for six to ten months out of the year. Wetland W contains three
distinct functional units, two of which are heavily manipulated. Part of Wetland W is formed from a
failed farm pond. The dam is breached but still retains ponded water with emergent vegetation. The
southeastern “lobe” of Wetland W is a manmade basin which functions similarly to a shallow retention
basin (Figure 3). Although clearly manmade, these features were more appropriately classified as
wetland than open water in their current condition. A Headwater Forest type wetland would have
naturally occurred in this location. The pond and basin provide poor quality habitat, water quality, and
hydrology functions. The third unit of Wetland W has generally unaltered topography but vegetation has
been manipulated.
3.3.3 Relic Hydric Soils
A licensed soil scientist (LSS) evaluated the site on March 11, 2020 to assess the extent of hydric soils on
site. The preliminary investigation determined that the entire East Mingo Creek valley contains hydric
soils. Since the hydric soil area covers the whole valley bottom and extends slightly upslope in hollows
and areas of groundwater discharge, a detailed investigation to field‐delineate the hydric soil boundary
was not necessary. Instead, a relief and elevation‐based approach to mapping hydric soil areas were
used. The LSS determined that soils within the East Mingo Creek valley are most like the Bibb series
(Coarse‐loamy, siliceous, active, acid, thermic, Typic Fluvaquents). The LSS report is included in Appendix
1. Additional soil observations by Wildlands during wetland delineation and general existing conditions
assessment further supported the presence of hydric soils within the entire valley.
3.3.4 Existing Hydrology
Seven groundwater gauges (GW) were installed on site in July 2021 and recorded data until early
February 2023 (Figure 3, Appendix 1). Growing season dates proposed for this Site are March 1 through
November 16 (260 days) and the hydroperiod criterion is proposed as 12%. A full discussion of growing
season date and hydroperiod selection follows in Section 8.0 Performance Standards. The water table at
GWs 1‐6 generally remained at soil depths significantly below 12 inches with only brief rises above a 12‐
inch depth. The water table receded rapidly after each rise. At GW 7, the water table generally remained
between soils depths of 12 to 22 inches during the early part of the 2022 growing season. GW 7 occurs
within Wetland C and wetland hydrology indicators were observed in this vicinity despite gauge data
East Mingo Creek Mitigation Site Final Mitigation Plan
Page 12 June 2023
indicating that the water table was not within 12 inches of the soil surface for a period of 14 days or
longer. It seems possible that this area does undergo saturation within 12 inches of the soil surface for
greater than 14 days during some years. GW 7 is representative of the hydrological impairment to
existing wetlands imposed by the incised stream channels and the toe of slope ditch along the western
edge of Wetland C. Summary data from the 2022 growing season is presented in Table 5.
Table 5: 2022 Groundwater Gauge Summary
Gauge
Consecutive Days in Growing
Season with Groundwater Table
Above 12 in. Depth
Consecutive Percent of Growing
Season with Groundwater Table
Above 12 in. Depth
Proposed Wetland
Approach
1 2 0.8 Re‐establishment
2 0 0 N/A1
3 0 0 Re‐establishment
4 0 0 Re‐establishment
5 0 0 Re‐establishment
6 1 0.4 Re‐establishment
7 1 0.4 Rehabilitation
1 GW 2 is in an area not proposed for wetland credit.
3.3.5 Existing Vegetation
Riparian buffers are largely absent from streams within the open pasture, including East Mingo Creek,
Rabbit Creek, Wolf Creek, and Beaver Creek and the downstream ends of Lamb Creek and Cow Creek.
The open pasture is dominated by pasture grasses such as fescue (Festuca sp.), as well as soft rush
(Juncus effusus), and dogfennel (Eupatorium capillifolium). Portions of the pasture near Beaver Creek
contain wetland indicator vegetation such as tag alder (Alnus serrulata), duck potato (Saggitaria
latifolia), and rushes (Juncus spp). The treelines adjacent to the easement in this southern area contain
swamp tupelo (Nyssa biflora), laurel oak (Quercus laurifolia) and white oak (Quercus alba). Multiflora
rose (Rosa multiflora) occurs around the pond and in patches throughout the pasture. Chinese privet
was observed at varied densities within wooded areas throughout the Site.
Floristic diversity increases in the wooded portion of the easement between Mouse Creek and the pond
outlet swale north of Snake Creek. Canopy species include swamp tupelo (Nyssa biflora), tulip poplar
(Liriodendron tulipifera), southern red oak (Quercus falcata), mockernut hickory (Carya tomentosa),
American elm (Ulmus americana), sugarberry (Celtis laevigata), eastern red cedar (Juniperus virginiana),
sweetbay magnolia (Magnolia virginiana), water oak (Quercus nigra), and red maple (Acer rubrum). Sub‐
canopy species include American beautyberry (Callicarpa americana), red mulberry (Morus rubra),
winterberry (Ilex decidua) and American holly (Ilex opaca). The understory layer includes a variety of
forbs and graminoids including violets (Viola spp.) and river cane (Arundinaria sp.).
The forested area on the northernmost portion of the site has prolific cover of Chinese privet. Observed
in lesser densities were wisteria (Wisteria sp.), mimosa (Albizia julibrissin), and Japanese honeysuckle
(Lonicera japonica).
3.4 Overall Functional Uplift Potential
The primary stressors onsite are livestock access, incision, scour, and the resulting hydrologic
disconnection of riparian wetlands. Livestock trampling has degraded streambanks and bedform and
limited biodiversity of vegetation onsite. These stressors led to NCSAM overall ratings of low for all
streams and low for intermittent streams. Without intervention, East Mingo Creek will continue to
incise, which will further disconnect riparian wetland hydrology. The further incision of East Mingo
would cause incision along the tributaries. Ultimately, functional uplift for this Site is linked to
improvement in and maintenance of hydrologic connectivity between streams and riparian wetlands.
East Mingo Creek Mitigation Site Final Mitigation Plan
Page 13 June 2023
Additionally, establishing a diverse riparian buffer will protect and enhance this connectivity. Functional
uplift for the site will be achieved through the following:
Restoring degraded stream channels to reduce erosion and reconnect streams to riparian
wetlands to restore hydrologic connection;
Removing extensive Chinese privet on site to increase vegetation biodiversity at the northern
portion of the Site;
Planting riparian buffers to shade streams, help stabilize streams, and promote woody debris in
system;
Protecting the Site with a conservation easement; and
Excluding livestock from the conservation easement.
These project components are described in Section 5 in terms of goals, objectives, and outcomes for the
project and in greater detail in Section 6 as the project site mitigation plan.
3.5 Site Constraints to Functional Uplift
Two internal easement breaks are included to maintain landowner access to adjoining tracts. Each
crossing proposed will be fenced and gated if needed for livestock exclusion. A ford crossing will be
located on East Mingo Creek and a ford crossing will be located on Lamb Creek. An existing overhead
utility line is located along Benson‐Hardee Road at the southern end of the project and an external
easement break is located here along East Mingo Creek up to the edge of the NCDOT right‐of‐way.
Livestock will be fenced out of this break and it will not be used as a crossing.
Cattle currently have access to the majority of the Site. After restoration, the landowner may remove
cattle from all or a part of the property. Wildlands will provide fencing along the perimeter of the
easement of any sections of the property where cattle will be present. The landowner will be required
to install fencing if cattle are returned to the property in the future.
The easement boundaries around all streams proposed for mitigation credit provide the required 50‐
foot minimum riparian buffer for Coastal Plain streams. The easement area will be marked per USACE
guidelines. The entire easement area can be accessed for construction, monitoring, and long‐term
stewardship from Benson‐Hardee Road and Banner Elk Road.
4.0 Regulatory Considerations
Table 5, below, is a summary of regulatory considerations for the Site. These considerations are
expanded upon in Sections 4.1‐4.4.
Table 6: Project Attribute Table Part 3
Regulatory Considerations
Parameters Applicable? Resolved? Supporting Docs?
Water of the United States ‐ Section 404 Yes Yes PCN
Water of the United States ‐ Section 401 Yes Yes PCN
Endangered Species Act Yes Yes Appendix 4
Historic Preservation Act Yes Yes Appendix 4
Coastal Zone Management Act No No N/A
FEMA Floodplain Compliance Yes Yes Appendix 4
Essential Fisheries Habitat No N/A N/A
East Mingo Creek Mitigation Site Final Mitigation Plan
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4.1 401/404
Care has been taken to design the streams to remain hydrologically connected to existing wetlands on‐
site, while minimizing impacts to those wetlands. The W. Fork East Mingo Creek will be filled during
project construction. This will be classified as a permanent stream impact and is necessary to restore the
East Mingo Creek as a single thread system. Most of the floodplain grading will be considered a
temporary impact to wetlands as hydrologic connectivity is anticipated to improve after channel
restoration, and vegetation will be re‐established. Any wetlands within the conservation easement and
outside of the limits of disturbance will be flagged prior to construction to prevent unintended impacts.
This will be noted in the final construction plans on the Erosion and Sediment Control Plan and Detail
plan sheets, as well as in the project specifications.
Table 6 estimates the anticipated impacts to wetland areas on this project. Final impacts will be
provided in the Pre‐Construction Notification, after proposed floodplain grading and the erosion control
plan are complete and will more accurately quantify these data. The numbers below reflect a
conservative estimate of potential impacts. The Pre‐Construction Notification, including this data, will be
provided to the IRT with the Final Mitigation Plan.
Table 7: Estimated Impacts to Project Wetlands
Jurisdictional
Feature Classification Acreage
Permanent (P) Impact Temporary (T) Impact
Type of
Activity
Impact Area
(acres)
Type of
Activity
Impact Area
(acres)
Wetland A
Bottomland
Hardwood
Forest
1.380
Conversion
to Stream
Resource
0.010 Floodplain
Grading 0.214
Wetland B
Bottomland
Hardwood
Forest
0.156
Conversion
to Stream
Resource
N/A Floodplain
Grading 0.015
Wetland C
Bottomland
Hardwood
Forest
1.248
Conversion
to Stream
Resource
0.170 Floodplain
Grading 0.927
Wetland D
Bottomland
Hardwood
Forest
0.041
Conversion
to Stream
Resource
0.023 Floodplain
Grading 0.018
Wetland E
Bottomland
Hardwood
Forest
0.033
Conversion
to Stream
Resource
0.010 Floodplain
Grading 0.023
Wetland F
Bottomland
Hardwood
Forest
0.679
Conversion
to Stream
Resource
N/A Floodplain
Grading 0.073
Wetland G
Bottomland
Hardwood
Forest
1.391
Conversion
to Stream
Resource
N/A Floodplain
Grading 0.045
Wetland H
Bottomland
Hardwood
Forest
0.497
Conversion
to Stream
Resource
N/A Floodplain
Grading 0.036
Wetland L
Bottomland
Hardwood
Forest
0.524
Conversion
to Stream
Resource
0.011 Floodplain
Grading 0.150
East Mingo Creek Mitigation Site Final Mitigation Plan
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Wetland M Headwater
Forest 1.287
Conversion
to Stream
Resource/
Permanent
Crossing
0.040 Floodplain
Grading 0.141
Wetland N Headwater
Forest 0.165 Permanent
Crossing 0.002 Floodplain
Grading N/A
Wetland O
Bottomland
Hardwood
Forest
0.109 Permanent
Crossing 0.023 Haul Road 0.017
Wetland P Headwater
Forest 0.456
Conversion
to Stream
Resource
0.001 Floodplain
Grading 0.039
Wetland Q
Bottomland
Hardwood
Forest
0.008 Permanent
Crossing 0.008 Floodplain
Grading N/A
Wetland R
Bottomland
Hardwood
Forest
0.025
Conversion
to Stream
Resource
0.007 Floodplain
Grading 0.018
Wetland S
Bottomland
Hardwood
Forest
0.022
Conversion
to Stream
Resource
0.012 Floodplain
Grading 0.010
Wetland T
Bottomland
Hardwood
Forest
0.020
Conversion
to Stream
Resource
N/A Floodplain
Grading 0.020
Wetland U
Bottomland
Hardwood
Forest
4.879
Conversion
to Stream
Resource
0.007 Floodplain
Grading 0.993
Wetland V
Bottomland
Hardwood
Forest
4.372
Conversion
to Stream
Resource
0.001 Floodplain
Grading 1.019
Wetland W Headwater
Forest 0.655
Conversion
to Stream
Resource
0.031 Floodplain
Grading 0.188
4.2 Threatened and Endangered Species
Wildlands utilized the US Fish and Wildlife Service’s (USFWS) Information for Planning and Consultation
(IPaC) and the NC Natural Heritage Program (NHP) databases to search for federally listed threatened
and endangered plant and animal species within the project parcels. The endangered red‐cockaded
woodpecker (Picoides borealis) (RCW) was the only listed species possibly occurring within the project
parcels. The red‐cockaded woodpecker requires open pine woodlands and savannahs with large, mature
trees. A pedestrian survey of the site performed on March 16, 2022 indicated there is no suitable habitat
for the red‐cockaded woodpecker. Thereby, Wildlands concludes the project will have “no effect” on the
RCW. USFWS replied to the public notice and stated it has “...no objection to the activity as described in
the permit application [public notice].” The official species list and correspondence with USFWS are
included in Appendix 4.
4.3 Cultural Resources / Conservation Lands / Natural Heritage Areas
The Site is not located near any entries listed on the National Register with the State Historic
Preservation Office (SHPO). SHPO reviewed the project prospectus and responded in a letter dated July
East Mingo Creek Mitigation Site Final Mitigation Plan
Page 16 June 2023
12, 2021 that they are “aware of no historic resources which would be affected by the project.” For
regulatory communication, please refer to Appendix 5.
4.4 FEMA Floodplain Compliance and Hydrologic Trespass
The Bank is represented on the Johnston County Flood Insurance
Rate Map (FIRM) Panels 1620 and 1528. A limited detailed study
has been performed on East Mingo Creek. The majority of the Bank
is mapped in special flood hazard area FEMA Zone AE. There is no
mapped floodway.
Due to the Priority 1 approach on East Mingo Creek within the
mapped Zone AE, it is likely that base flood water surface
elevations will change from the published elevations. If this occurs,
a Conditional Letter of Map Revision (CLOMR) may be required
prior to construction. If required, a Letter of Map Revision (LOMR)
will be submitted after the project is constructed. Wildlands will
coordinate with the Town of Benson floodplain administrator to
obtain the appropriate floodplain development permit for the
project.
The Bank will be designed to avoid adverse floodplain impacts or
hydrologic trespass on adjacent properties or local roadways.
5.0 Mitigation Site Goals and Objectives
The overall goal of the project is to improve stream and riparian wetland function through stream
restoration and riparian buffer re‐vegetation. Project goals have been set in order to achieve the
functional uplift outlined in Section 3 and alleviate the watershed stressors. The project goals and
related objectives are described in Table 7, below.
FIRM Panel 1620
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Table 8: Mitigation Goals and Objectives
Goal Objective Expected Outcomes
Exclude livestock
from streams and
wetlands.
Remove livestock from site or install
livestock exclusion fencing along the
conservation easement.
Reduce sediment, turbidity, nutrient, and fecal
coliform bacteria inputs.
Improve stream
channel stability.
Construct stream channels that will
maintain stable cross‐sections, patterns,
and profiles over time. Repair eroding
stream banks with bioengineering.
Reduce shear stress on channel boundary. Reduce
sediment inputs from bank erosion.
Improve instream
habitat.
Install habitat features such as
constructed riffles, cover logs, and brush
toes in restored/enhanced streams. Add
woody materials to channel beds.
Construct pools of varying depth.
Increase and diversify available habitats for
macroinvertebrates, fish, and amphibians, leading
to colonization and an increase in biodiversity over
time. Add complexity including large woody debris
(LWD) to the streams.
Reconnect
channels with
floodplains.
Construct stream channels with
appropriate bankfull dimensions and
depth relative to the existing floodplain.
Allow more frequent flood flows to disperse on the
floodplain. Support geomorphology and higher‐
level functions. Improve wetland hydrology.
Improve wetland
hydrology.
Remove livestock to allow soil profiles to
stabilize. Remove drain effect of
channelized streams and floodplain
ditches.
Increased surface water residency time will provide
contact treatment and groundwater recharge
potential.
Restore and
enhance native
floodplain and
streambank
vegetation.
Plant native canopy and understory
species in riparian and wetland zones and
plant native shrub and herbaceous species
on streambanks. Treat invasive species
within the project area.
Reduce sediment inputs from bank erosion and
runoff. Increase nutrient cycling and storage in
floodplain. Provide riparian habitat. Add a source
of LWD and organic material to streams. Support
all stream functions.
Permanently
protect the project
from harmful uses.
Establish a conservation easement on the
Bank.
Protect Bank from encroachment on the riparian
corridor and direct impact to streams and
wetlands. Support all stream functions.
6.0 Design Approach and Mitigation Work Plan
6.1 Design Approach Overview
The design approach (Figure 8) for this site was developed to maximize functional uplift and meet the
goals and objectives described in Section 5. The table below summarizes the primary impairments to
each stream reach and the proposed restoration activity.
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Table 9: Functional Impairments and Restoration Approach
Resource Reach Primary Stressors/Impairments Restoration Approach
East Mingo
Creek
1
Incised, unstable pattern, streambank scouring, mass
wasting of bank material, lack of bedform diversity,
livestock access
Restoration – Priority 1
2 Livestock access, lack of riparian buffer Enhancement II
Lizard Creek ‐ Incised, isolated erosion, livestock access Restoration – Priority 1
Cricket Creek 1 Livestock access, invasive monoculture riparian
understory Enhancement II
2 Incised, Isolated erosion, livestock access Restoration – Priority 1
Snake Creek
1 Livestock access, lack of riparian understory Enhancement II
2 Incision, active headcuts, lack of riparian understory,
livestock access Restoration – Priority 1
Snake Creek
Anabranch ‐ Livestock access, lack of riparian understory Enhancement II (Not for
Credit)
Deer Creek 1 Livestock access, lack of riparian understory Enhancement II
2 Restoration – Priority 1
Mouse Creek 1 Livestock access, lack of riparian understory Enhancement II
2 Incised, Isolated erosion, livestock access Restoration – Priority 1
Rabbit Creek 1 Livestock access, lack of riparian understory Enhancement II
2 Incised, Isolated erosion, livestock access Restoration – Priority 1
UT to Rabbit
Creek ‐ Livestock access, lack of riparian understory Enhancement II
Wolf Creek ‐ Isolated erosion, livestock access Enhancement II
Lamb Creek
1 Livestock access, lack of riparian understory Enhancement II
(Headwater Guidance)
2 Livestock access, lack of pattern, lack of riparian
buffer, bank trampling Restoration – Priority 1
Cow Creek ‐ Livestock access, lack of riparian understory Enhancement II
Beaver Creek ‐ Ponded headwater, livestock access, lack of riparian
buffer, incision in failed pond dam.
Restoration – Priority 1
and Priority 2
UT to Beaver
Creek ‐ Livestock access, lack of riparian buffer Restoration – Priority 1
6.2 Reference Streams
Reference reaches were chosen to inform the design because of their similarities to the Site streams
including drainage area, valley slope, morphology, and bed material (Figure 9). They were also chosen
for their examples of pool formation using woody debris in low slope conditions. Geomorphic
parameters for these reference reaches are summarized in Appendix 4 (except for reference reaches
only used for discharge analysis). A brief description of each reference reach is included in Table 9.
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Table 10: Stream Reference Data Used in Development of Design Parameters
Reference Reach Stream
Type Landscape Position Chosen For Used For Used on
streams
Scout West 1 E5/C5b
Headwater, steeper
tributary (~2.6%),
flowing into broad
flat mainstem
Similar region to Site with
same controlling hydrology
Q, Dimension,
Pattern,
Profile
Tributaries
Scout West 2 E5 Wide, low slope
alluvial valley.
Sandbed with examples of
woody debris pool
structures, pattern, and
similar landscape position to
tributaries
Q, Dimension,
Pattern,
Profile
Tributaries
Scout East 2 E5 Wide, low slope,
alluvial valley
Channel slope, size, and
pattern, and habitat
structures
Q, Dimension,
Pattern,
Profile
Tributaries
Johanna E5/C5 Wide, low slope,
alluvial valley
Channel dimensions,
landscape position, habitat
structures, pattern, slope
Q, Dimension,
Pattern,
Profile
East
Mingo
Creek and
Tributaries
Outland Branch C6C/D6 Low slope, alluvial
valley
Channel dimensions,
landscape position, habitat
structures, pattern, slope
Q, Dimension,
Pattern,
Profile
East
Mingo
Creek and
Tributaries
Raven Rock Site
2 E4b Low slope, alluvial
valley Similar drainage area Q Tributaries
Acorn Millpond
Reach 1 C6 Low slope, alluvial
valley Similar drainage area Q Tributaries
Acorn Millpond
Reach 2 C6 Low slope, alluvial
valley Similar drainage area Q
East
Mingo
Creek and
Tributaries
6.3 Reference Wetland and Vegetation
One reference wetland, Johanna Creek, which has been monitored for a period of greater than five
years was identified for this project. Johanna Creek is within 30 miles of the Site and was initially
identified in 2001 by Buck Engineering and was used by Wildlands for the Devils Racetrack Mitigation
Site that closed out in 2021. Hydrology at the Site was maintained continuously for over 10 years. The
Site is an example of a Coastal Plain small stream swamp as described by Schafale and Weakley (1990).
These systems exist as the floodplains of small blackwater and brownwater streams in which separate
fluvial features and associated vegetation are too small or poorly developed to distinguish. Hydrology of
these systems is palustrine, intermittently, temporarily, or seasonally flooded. Flows tend to be highly
variable with floods of short duration and periods of very low flow. Johanna Creek reference wetland
has similar hydrologic controls as the Site with the main stream channel flowing through the Site and
small drainages that provide additional water to the floodplain during wet periods. Due to the shallow,
unincised condition of the main stream at Johanna Creek, the high water table conditions are sustained
across the active floodplain. Monitoring data for Johana Creek presented below was taken between
East Mingo Creek Mitigation Site Final Mitigation Plan
Page 20 June 2023
2006 and 2010. The table below presents the results for the growing seasons. The hydrology results
reported are the consecutive period of the growing season during which the water table was within 12
inches of the soil surface. Annual results are averaged over the five‐year period to provide a range of
anticipated conditions for comparison to the restoration site.
Table 11: Reference Wetland Hydrology Results 2006‐2010
Max Hydroperiod by Year (Growing Season 17‐Mar through 5‐Nov, 232 days)
Reach 2006 2007 2008 2009 2010 Average
Johanna Ref MW1 8 3 2 3 18 6.8
Johanna Ref MW2 8 8 8 15 14 10.6
Johanna Ref AW3 29 19 22 17 18 21.0
Johanna Ref MW4 9 19 16 16 13 14.6
Johanna Ref MW5 0 1 0 0 13 2.8
Soils located within the wetland areas of the reference site are mapped as the Bibb series, which has
moderate permeability and the seasonal high water table is within 0.5 to 1.5 feet of soil surface. (SCS,
1994). Wildlands confirmed the soil series with an onsite investigation.
Historical aerials reveal that the Johanna Creek reference wetland area has not been cleared since 1939.
The reference wetland area has vegetation that is classified as Coastal Plain small stream swamp and
bottomland forest types (Schafale & Weakley, 1990). Dominant species include swamp chestnut oak
(Quercus michauxii), laurel oak, red maple, sweetbay magnolia, river birch (Betula nigra), tulip poplar,
sweetgum (Liquidambar styraciflua), green ash (Fraxinus pennsylvanica), and sycamore (Platanus
occidentalis). Common understory vegetation includes ironwood (Carpinus caroliniana), American holly,
leucothoe (Leucothoe axillaris), sweet pepperbush (Clethra alnifolia), and swamp titi (Cyrilla
racemiflora). The herbaceous stratum consists of microstegium (Microstegium vimineum), false nettle
(Boehmeria cylindrica), jewel‐weed (Impatiens capensis), cinnamon fern (Osmunda cinnamomea),
sensitive fern (Onoclea sensibilis), greenbrier (Smilax spp.), Virginia creeper (Parthenocissus
quinquefolia), grape (Vitis spp.), poison ivy (Toxicodendron radicans), and honeysuckle.
6.4 Design Channel Morphological Parameters
A combination of reference reach data and designer experience was used to develop design parameters
for streams onsite. Key morphological parameters are summarized in tables below and extended
parameter tables can be found in Appendix 1.
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Table 12: Summary of Morphological Parameters for East Mingo Creek
Parameter
Existing
Parameters Reference Parameters Proposed
Parameters
East Mingo Creek
Reach 1 Cedar Creek Johanna Outland Branch East Mingo Creek
Reach 1
min max min max min max min max min max
Valley Width (ft) 210 395 ‐ ‐ ‐ ‐ ‐ ‐ 210 395
Contributing Drainage Area
(acres) 2,067 2,605 576 518 2,067
Channel/ Reach
Classification F5 E5 E5/C5 C6c/D6 C5
Design Discharge Width (ft) 15.0 16.8 11.1 12 9.7 10.6 12.1 16
Design Discharge Depth (ft) 1.3 1.7 1.8 0.80 0.5 0.6 1.2
Design Discharge Area (ft2) 18.9 22.3 18.9 22.2 7.2 7.8 5.5 6.1 18.6
Design Discharge Velocity
(ft/s) 1.6 1.7 3.0 3.1 1.8 1.9 1.9 2.1 1.9
Design Discharge (cfs) 35 57 68 14 10.3 13.1 35
Water Surface Slope (%) 0.12 0.30 0.22 0.70 0.20
Sinuosity 1.22 1.2 1.2 1.2 1.1 1.3
Width/ Depth Ratio 11.9 12.7 6.54 6.6 10.1 19.7 18.4 26.3 14
Bank Height Ratio 2.4 2.9 1.0 1.0 1.0 1.0 1.0 1.0 1.0
Entrenchment Ratio 1.4 >2.2 8.0 9.6 20.7 23.5 >2.2
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Page 22 June 2023
Table 13: Summary of Morphological Parameters for Beaver Creek, Cricket Creek, and Deer Creek
Parameter
Existing Parameters Reference Parameters Proposed Parameters
Beaver
Creek
Cricket
Creek
Reach
2
Deer
Creek
Reach
2
Scout West 1 Scout West 2 Scout East 2 Beaver
Creek
Cricket
Creek
Reach
2
Deer
Creek
Reach
2 min max min max min max
Valley Width (ft) 40 65 >100 ‐ ‐ ‐ ‐ ‐ ‐ 50 65 >100
Contributing Drainage
Area (acres) 14.7 1.7 20.5 38.4 218 429 3.2 1.69 20.48
Channel/ Reach
Classification E5b E5b C5b E/C5b E5 E5 C5 C5 C5
Design Discharge Width
(ft) 2.7 2.1 4.3 2.6 6.3 5.6 7.6 4.7 6.1 5.6 7.0 5.6
Design Discharge Depth
(ft) 0.8 0.5 0.2 0.30 0.50 0.7 1.0 1.1 1.3 0.44 0.6 0.44
Design Discharge Area
(ft2) 2.5 1.1 1.1 1.2 2.0 5.3 5.4 6 6.9 2.5 3.9 2.5
Design Discharge
Velocity (ft/s) 6.4 2.9 3.3 1.3 2.3 1.2 1.2 2.9 2.5 1.2 1.2 1.5
Design Discharge (cfs) 2.9 1.4 3.4 2.6 6.4 17.5 2.9 1.4 3.4
Water Surface Slope
(%) 5.6 3.2 4.0 2.6 4.0 1.68 2.3 0.19 1.1
Sinuosity 1.1 1.08 1.16 1.1 1.2 1.2 1.20 1.20 1.20
Width/ Depth Ratio 3.2 7.9 17.3 5.4 19.9 5.7 11 3.6 5.4 13.0 13.0 13.0
Bank Height Ratio 1.0 2.1 1.4 1.1 1.3 1.1 1.2 1.0 1.0 1.0 1.0
Entrenchment Ratio >2.2 1.9 >2.2 >2.2 >2.2 >2.2 >2.2 >2.2 >2.2
East Mingo Creek Mitigation Site Final Mitigation Plan
Page 23 June 2023
Table 14: Summary of Morphological Parameters for Lamb Creek, Lizard Creek, and Mouse Creek
Parameter
Existing Parameters Reference Parameters Proposed Parameters
Lamb
Creek
Reach 2
Lizard
Creek
Reach
2
Mouse
Creek
Reach
2
Scout West 1 Scout West 2 Scout East 2 Lamb
Creek
Reach
2
Lizard
Creek
Reach
2
Mouse
Creek
Reach
2
min max min max min max
Valley Width (ft) 50 75 >100 ‐ ‐ ‐ ‐ ‐ ‐ 50 75 >100
Contributing Drainage
Area (acres) 14.1 33.3 3.8 38.4 218 429 14.08 33.28 3.84
Channel/ Reach
Classification E5 E5b E5 E/C5b E5 E5 C5 C5 C5
Design Discharge
Width (ft) 16.6 2.7 5.5 2.6 6.3 5.6 7.6 4.7 6.1 5.4 7 0.31
Design Discharge
Depth (ft) 0.3 0.3 0.4 0.30 0.50 0.7 1.0 1.1 1.3 0.43 0.55 4
Design Discharge Area
(ft2) 1.5 0.93 2.3 1.2 2.0 5.3 5.4 6 6.9 2.3 3.9 1.3
Design Discharge
Velocity (ft/s) 2.3 3.7 3.7 1.3 2.3 1.2 1.2 2.9 2.5 1.3 1.2 1.2
Design Discharge (cfs) 2.8 4.5 1.5 2.6 6.4 17.5 2.8 4.5 1.5
Water Surface Slope
(%) 1.6 3.6 2.6 2.6 4.0 1.68 1.5 1.3 0.48
Sinuosity 1.11 1.03 1.20 1.1 1.2 1.2 1.20 1.20 1.20
Width/ Depth Ratio 16.6 7.8 12.8 5.4 19.9 5.7 11 3.6 5.4 13.0 13.0 13.0
Bank Height Ratio 1.0 1.9 1.8 1.1 1.3 1.1 1.2 1.0 1.0 1.0 1.0
Entrenchment Ratio >2.2 >2.2 >2.2 >2.2 >2.2 >2.2 >2.2 >2.2 >2.2
East Mingo Creek Mitigation Site Final Mitigation Plan
Page 24 June 2023
Table 15: Summary of Morphological Parameters for Rabbit Creek, Snake Creek, and UT to Beaver Creek
Parameter
Existing Parameters Reference Parameters Proposed Parameters
Rabbit
Creek
Reach 2
Snake
Creek
Reach
2
UT to
Beaver
Creek
Scout West 1 Scout West 2 Scout East 2 Rabbit
Creek
Reach
2
Snake
Creek
Reach
2
UT to
Beaver
Creek min max min max min max
Valley Width (ft) >100 > 100 20 ‐ ‐ ‐ ‐ ‐ ‐ >100 > 100 20
Contributing Drainage
Area (acres) 37.8 147.2 3.2 38.4 218 429 37.76 147.2 14.72
Channel/ Reach
Classification C5 E5 C5b E/C5b E5 E5 C5 C6 B5
Design Discharge
Width (ft) 6.2 5.9 2.3 2.6 6.3 5.6 7.6 4.7 6.1 6.2 8.6 2.5
Design Discharge
Depth (ft) 0.5 0.7 0.2 0.30 0.50 0.7 1.0 1.1 1.3 0.5 0.69 1.5
Design Discharge Area
(ft2) 3.0 4.0 0.4 1.2 2.0 5.3 5.4 6 6.9 3.0 6.2 0.6
Design Discharge
Velocity (ft/s) 3.4 3.9 3.5 1.3 2.3 1.2 1.2 2.9 2.5 1.7 1.6 3.4
Design Discharge (cfs) 4.8 10 1.0 2.6 6.4 17.5 4.8 10 1.0
Water Surface Slope
(%) 1.8 1.6 7.0 2.6 4.0 1.68 0.51 1.2 7.9
Sinuosity 1.09 1.29 1.12 1.1 1.2 1.2 1.20 1.20 1.20
Width/ Depth Ratio 12.8 8.7 12.3 5.4 19.9 5.7 11 3.6 5.4 13.0 13.0 10.0
Bank Height Ratio 2.0 1.8 1.4 1.1 1.3 1.1 1.2 1.0 1.0 1.0 1.0
Entrenchment Ratio 2.1 >2.2 >2.2 >2.2 >2.2 >2.2 >2.3 >2.2 >2.2
6.5 Design Bankfull Discharge Analysis
The primary design goal for restoration reaches onsite is to hydraulically connect the reaches to their
existing floodplains to prevent continued incision along Site streams. This means selecting a design
discharge that allows for frequent overbank events. Multiple methods were used to develop design
discharges for restoration reaches, including published regional curve data (Doll et al. 2003), reference
reach data, and existing bankfull indicators. Additionally, Wildlands performed a regional flood
frequency analysis using U.S. Geological Survey (USGS) gage sites. Results are shown in Table 15 and
illustrated in Figure 10.
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Page 25 June 2023
Table 16: Summary of Design Discharge Analysis
East
Mingo
Creek
Reach 1
Snake
Creek
Rabbit
Creek
Reach 2
Lizard
Creek
Deer
Creek
Reach 2
Lamb
Creek
Reach 2
Beaver
Creek
Mouse
Creek
Reach 2
Cricket
Creek
UT to
Beaver
Creek
DA (acres) 2,067 185 34 32 20 14 12 9.4 1.7 0.5
DA (sq. mi.) 3.2 0.29 0.053 0.051 0.031 0.021 0.019 0.015 0.0026 0.00075
NC Rural Coastal
Plain Regional
Curve (cfs)
39 6.8 4.1 1.9 1.4 1.0 1.0 0.8 0.2 0.09
Wildlands
Regional
USGS
Flood
Frequency
Analysis
(cfs)
1.2‐
year
event
38 9.9 3.8 3.7 2.9 2.3 2.2 1.9 0.7 0.4
1.5‐
year
event
56 16 6.7 6.6 5.2 4.2 4.0 3.5 1.4 0.8
Site‐Specific
Reference Reach
Curve (cfs)
24 8.5 4.5 4.0 3.3 2.8 2.7 2.4 1.1 0.7
Manning's
Equation
From
Surveyed
XS (cfs)
XS4 38
XS5 23
XS6 3.5
XS7 3.6
XS8 8.7
Design Q 35 10 4.8 4.5 3.4 2.8 2.9 2.5 1.4 0.8
The results of the discharge analysis provided a range of discharge values. As illustrated in Figure 12, the
most concurrence was found between values for the site‐specific reference reach curve and the
Wildlands regional flood frequency analysis 1.2‐ or 1.5‐year storm. The final design values are generally
in line with the site‐specific reference reach curve. This was chosen for its development using sites of
similar size within the Coastal Plain.
6.6 Sediment Transport Analysis
Wildlands performed a qualitative assessment of sediment supply and sources in the project watershed
using past, current, and projected future land use conditions from the National Land Cover Database
(NLCD), historic and current aerial photography, and future county zoning maps.
The prominent sediment source within the Site is stream bank erosion that is exhibited on Reach 1 of
East Mingo Creek. A competence analysis was performed using shear stress as calculated by the Shields
(1936) and Andrews (1984) equation described by Rosgen (2001). The results of the competence
analysis are shown in Table 16.
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Page 26 June 2023
Table 17: Results of Competence Analysis
East
Mingo
Creek
Reach 1
Lizard
Creek
Snake
Creek
Reach 2
Deer
Creek
Reach 2
Mouse
Creek
Reach
2
Rabbit
Creek
Reach
2
Lamb
Creek
Reach 2
Beaver
Creek
Reach 1
Design Abkf (sq ft) 18.6 3.9 6.2 2.5 1.3 3.0 2.3 2.5
Design Wbkf (ft) 16.0 7.0 8.9 5.6 4.0 6.2 5.4 5.6
Design Dbkf (ft) 1.16 0.55 0.69 0.44 0.31 0.49 0.43 0.44
Design Schan (ft/ft) 0.0022 0.0025 0.0033 0.0050 0.0050 0.0055 0.012 0.023
Design Bankfull Velocity
(fps) 1.9 1.2 1.6 1.5 1.5 1.7 1.3 1.2
Bankfull Shear Stress, t
(lb/sq ft) 0.15 0.08 0.14 0.13 0.09 0.16 0.11 0.09
Movable particle size (mm) 38.4 24.3 35.5 34.1 26.6 40.0 29.3 25.3
The competence analysis was used to guide channel plan, pattern, profile, and material sizing. Site
streams are predominately sandbed with interspersed gravel. East Mingo Creek, Lizard Creek, Snake
Creek, and Beaver Creek have low valley slopes and low channel slopes. To ensure adequate sediment
transport competence was maintained, reaches were designed with longer pools and shorter riffles. This
increased localized velocities at the stream riffles. The competence analysis on these reaches indicated
reaches could transport medium sized gravel, but not the maximum particle size. Knowing localized
shear stresses could be higher based on individual riffle velocities, the bed material will be sized to pass
sand and small gravels, with the D50 and Dmax being similar to existing conditions. Additionally, since
the Site is prone to degradation, design will include threshold structures to prevent head cuts from
forming and migrating. Such structures will include log drops, constructed riffles with rock, and
combinations of the two.
6.7 Project Implementation
6.7.1 East Mingo Creek
East Mingo Creek Reach 1 will be restored using a Priority 1 restoration approach. The stream will be
reconnected with an active floodplain and the channel will be reconstructed with stable dimension,
pattern, and profile to transport water and sediment delivered to the system. Streams will meander
through their natural valleys, restoring pattern to a previously straightened and ditched system. East
Mingo Creek Reach 1 is a very flat section of the project. Therefore, as discussed in the sediment
transport sections, pools were designed flat to allow for grade drop over riffles. Stream structures in this
reach are placed primarily for habitat formation and maintenance as there is low shear stress. Woody
material will be incorporated as much as possible to mimic conditions found in the reference reaches.
East Mingo Creek Reach 2 will incorporate similar habitat structures to provide variability within the
reach.
6.7.2 Lizard Creek
Lizard Creek will be restored using a Priority 1 restoration approach to reconnect the channel to the
historic floodplain. The stream will meander until it flows into East Mingo Creek. Structures along this
reach will be both grade control and habitat‐driven, incorporating logs and woody debris to promote
stable fish and macroinvertebrate habitat.
6.7.3 Cricket Creek
Enhancement II is proposed for Cricket Creek Reach 1. Native riparian buffers will be planted and
invasives will be treated. Reach 2 will be restored using a Priority 1 approach and connected to the
East Mingo Creek Mitigation Site Final Mitigation Plan
Page 27 June 2023
proposed elevation of East Mingo Creek Reach 1. Structures made with logs and woody debris will be
incorporated to control grade and provide fish and macroinvertebrate habitat.
6.7.4 Snake Creek and Snake Creek Anabranch
Snake Creek Reach 1 is slated for Enhancement II. Livestock will be removed from the channel.
Additionally, invasive species within the riparian buffer will be treated. Reach 2 consists of a small reach
downstream of a headcut. The headcut will be stabilized and Reach 2 will be fully restored, introducing a
meander before meeting up with East Mingo Creek. Structures along this reach will be both grade
control and habitat‐driven, incorporating logs and woody debris to promote stable fish and
macroinvertebrate habitat. Snake Creek Anabranch is not for credit and will be connected into the newly
restored East Mingo Creek.
6.7.5 Deer Creek, Mouse Creek, and Rabbit Creek
Enhancement II is proposed for the upstream reaches of Deer Creek, Mouse Creek and Rabbit Creek.
Livestock will be removed from the Site or excluded from the conservation easement using fencing.
Additionally, native riparian buffers will be established, and the invasive colony of Chinese privet will be
treated. Reach 2 on each Creek will be restored using a Priority 1 approach and connected to adjacent
floodplain wetlands and proposed East Mingo Creek. Structures along this reach will be both grade
control and habitat‐driven, incorporating logs and woody debris to promote stable fish and
macroinvertebrate habitat.
6.7.6 UT to Rabbit Creek
Enhancement II is proposed for UT to Rabbit Creek. Livestock will be removed from the Site or excluded
from the conservation easement using fencing. Additionally, native riparian buffers will be established,
and the invasives will be treated.
6.7.7 Wolf Creek
Enhancement II is proposed for Wolf Creek. Livestock will be removed from the Site or excluded from
the conservation easement using fencing. Additionally, native riparian buffers will be established, and
the invasives will be treated. Bedform diversity will be introduced where Wolf Creek is connected to
proposed East Mingo Creek. This section will also include a structure for grade control and woody debris
to promote stable fish and macroinvertebrate habitat.
6.7.8 Lamb Creek
Enhancement II is proposed for Lamb Creek Reach 1. Livestock will be removed from the Site or
excluded from the conservation easement using fencing. Additionally, native riparian buffers will be
established, and the invasives will be treated. A ford crossing will be constructed in the easement break
just upstream of where Lamb Creek enters the East Mingo floodplain. Downstream of the crossing,
Reach 2 will be restored using a Priority 1 approach and connected to adjacent riparian wetlands with
appropriate pattern. Structures along this reach will be both grade control and habitat‐driven,
incorporating logs and woody debris to promote stable fish and macroinvertebrate habitat.
6.7.9 Cow Creek
Enhancement II is proposed for Cow Creek. Livestock will be removed from the Site or excluded from the
conservation easement using fencing. Additionally, native riparian buffers will be established, and the
invasives will be treated. There are existing farm ponds upstream of Cow Creek that are outside of the
project parcel. While these ponds control flow to Cow Creek, Wildlands does not have any control over
them or their respective property parcel.
East Mingo Creek Mitigation Site Final Mitigation Plan
Page 28 June 2023
6.7.10 Beaver Creek and UT to Beaver Creek
The pond and dam on Beaver Creek will be removed and Beaver Creek and UT to Beaver Creek will be
restored using Priority 1 restoration from its origin until it reaches the floodplain of East Mingo Creek,
where it spreads out into an existing wetland. Structures along this reach will be both grade control and
habitat‐driven, incorporating logs and woody debris to promote stable fish and macroinvertebrate
habitat.
6.7.11 Wetland Design Implementation
Proposed wetland mitigation at the Site includes re‐establishment of drained, historic wetlands and
rehabilitation and enhancement of existing jurisdictional wetland features. Wetland re‐establishment is
proposed on 16.642 acres of relic hydric soils that lack a contemporary wetland hydrology regime.
Wetland rehabilitation is proposed on 4.174 acres of existing jurisdictional wetland that have
hydrological and vegetation impairments. 10.087 acres are proposed for wetland enhancement via
vegetation improvements and cattle exclusion.
Multiple restoration components will restore wetland hydrology to areas proposed for wetland
rehabilitation and re‐establishment. Elevating the East Mingo Creek streambed will reduce groundwater
drainage to the channel and increase interaction of the stream with floodplain wetlands. Although the
West Fork of East Mingo Creek is currently classified as a jurisdictional stream channel, it appears to
have formed as a result of disturbance and accelerated erosional forces. Portions of this channel have a
wetted bottom through much of the year; however, it is mostly stagnant during normal flow conditions
and only conveys flow during higher stages of East Mingo Creek. The West Fork of East Mingo Creek is
several feet deep and contributes to draining historic floodplain wetlands. Filling this poorly‐functioning
channel is proposed to favor wetland restoration and a net ecological improvement is expected as a
result. The non‐jurisdictional, erosional channels and the toe slope ditch up valley of West Fork of East
Mingo Creek will also be filled since they have a similar drainage effect on historic wetlands as well as a
partial drainage effect to portions of Wetland C.
Wetland F and Wetland G discharge groundwater. Cattle disturbance has allowed this discharging water
to form erosional channels connecting them to the current East Mingo Creek channel. Re‐aligning East
Mingo Creek will eliminate this direct discharge to the channel and favor soil saturation between
Wetlands F and G and the new stream channel.
Part of Wetland W is formed in a former pond bed. Following removal of the failed dam, construction of
a stream channel, and floodplain grading, a more naturally functioning wetland is expected to develop in
this area. This portion of Wetland W is proposed for rehabilitation credit.
Wetlands proposed for enhancement generally have sufficient wetland hydrology such that function will
improve over time with removal of stressors and vegetation improvements. Cattle will be excluded,
appropriate native hydrophytic plant communities will be established, and invasive species populations
will be treated in all wetland credit areas.
6.8 Vegetation, Planting Plan, and Land Management
6.8.1 Vegetation and Planting Plan
The objective of the planting plan is to establish, over time, a thriving riparian buffer composed of native
species. The planting plan resembles a Coastal Plain small stream swamp community type for most
portions of the Site. In the long‐term ponded areas (4.6 acres), it resembles a transitional natural
community of mixed shrubs, bald cypress (Taxodium distichum), and blackwater bottomland hardwoods
that mimics the dynamic nature of frequently flooded landscapes in the Upper Coastal Plain.
East Mingo Creek Mitigation Site Final Mitigation Plan
Page 29 June 2023
Though land use history has drastically altered the floristic composition throughout the Site, the
observed existing vegetation in the wooded areas, the primary soil type, Bibb, and the blackwater
nature of East Mingo Creek are indicators of a Coastal Plain small stream swamp, inferring one of our
target natural communities. Coastal Plain small stream swamps are explicitly described as being highly
varied in species composition, though Carolina Vegetation Survey data indicates that sweetgum, water
oak, laurel oak, red maple, loblolly pine, tulip poplar, and swamp tupelo are most commonly the
dominant canopy species (Schafale, 2012). The proposed tree and shrub species compositions for this
Site reflect the native existing vegetation, which includes many of the indicator species for Coastal Plain
small stream swamps. Some adaptations were made to target community species composition based on
commercial availability, and to omit tree species (red maple, sweetgum, and loblolly pine).
Portions of the project are open canopy and ponded with up to 3 inches of standing water for prolonged
periods of the year (Figure 3). These areas are referred to as long‐term ponded areas in figures,
discussion text, and planting tables. They contain wetland indicator vegetation such as tag alder, duck
potato, and rushes. Where not grazed they transition into forested wetland primarily comprised of
swamp tupelo and laurel oak. Based on the flooding regime and surrounding indicator vegetation, the
target natural community at the end of the monitoring period is a transitional community with
components of both blackwater bottomland hardwood (swamp transition subtype) and Coastal Plain
wet shrubland (Hall and Howard, 2022). The long‐term ponded area planting zones are designed to
encompass all the non‐forested ponded areas as well as some surrounding wetlands not found to be
frequently flooded. The zones were simplified for the labor force planting the trees.
Blackwater bottomland hardwood (swamp transition subtype) has a large component of bald cypress
and swamp tupelo. Overcup oak (Quercus lyrata) and laurel oak are strong indicator species as well,
with understory and herbaceous forest strata generally lacking (Schafale, 2012). The indicator
vegetation described in coastal plain general wet shrublands, as defined by the North Carolina
Biodiversity Project (Hall and Howard, 2022), is not well matched to the existing vegetation found
onsite. However, biogeographic foundations of this natural community, such as ponding regime, align to
the conditions of the Site. The Site has a long history of anthropogenic disturbance that may have
inhibited the establishment of the dominant species described in Hall and Howard’s Coastal Plain
general wet shrubland (such as swamp highbush blueberry (Vaccinium formosum) or southern
arrowwood (Viburnum dentatum). Most of the indicator shrub species for this natural community type
are not commercially available. Wildlands will add flood‐tolerant shrubs such as tag alder, buttonbush
(Cephalanthus occidentalis), and winterberry to the blackwater bottomland hardwood forest (swamp
subtype) to provide the ecological function of a coastal plain general wet shrubland succeeding to
hardwood forest.
Given the hydrology of the long‐term ponded areas, it can be expected that tree growth will be
influenced by the duration of ponding. By including a mixture of trees, shrubs, bare root size class and
live stake size class, the mid‐successional and transitional nature of this planting zone has an integrated
adaptability to mitigate the risk of growth impediment due to ponding. It is proposed that the
performance criteria for the blackwater bottomland hardwood forest (swamp transition subtype) be the
survival of 180 stems per acre averaging five feet tall at the end of MY7. Performance standards are
further explained in section 8.0 Performance Standards. Research has shown that bare roots planted
into standing water shed their existing root systems and grow entirely new root systems adapted for
prolonged saturated conditions (Conner, 2004). According to Conner, the species in his research found
to be most tolerant of planting into standing water are bald cypress, black willow, and water tupelo. At
the Falling Creek Mitigation Site and McClenny Mitigation Site, bald cypress proved to be a strong
performer in vegetation establishment of heavily saturated soils.
East Mingo Creek Mitigation Site Final Mitigation Plan
Page 30 June 2023
For these reasons, our transitional community has a strong bald cypress component. Practical
considerations for vegetation establishment in this area led to some adaptations to the target
community species composition, including commercial availability. Several native species such as silky
willow and buttonbush were selected based on commercial availability of live stakes, which will develop
flood‐tolerant roots without the traumatic process of shedding existing roots. Twenty‐five percent of the
stems to be planted in this zone will be live stakes.
The restored buffer will improve riparian and wetland habitat, enhance stream stability, shade the
streams and wetlands, and provide a source of organic material. Non‐forested areas within the
conservation easement will be revegetated with a combination of trees, shrubs, forbs, and grasses. The
selected species assemblage is based on the existing natural community types, reference sites, and
professional judgement regarding species establishment in the anticipated Site conditions. The
streambanks will be planted with regionally appropriate live stakes and herbaceous plugs. Permanent
native seed mixes are based on the proposed target communities, professional judgement regarding
seed establishment, and commercial availability. Separate seed mixes were developed for wetland areas
and will be broadcast on all disturbed areas in the conservation easement. The complete planting plan is
found in the preliminary design plans. Planting tables are located on Sheet 2.0 of the draft plans located
in Appendix 9.
The non‐wooded riparian buffer areas will be planted with bare root seedlings. Species planted as bare
roots will be planted at 12‐foot by 6‐foot spacing. In addition, streambanks will be planted with live
stakes. Herbaceous plugs will be planted throughout the Site in combination with instream structures to
add toe‐of‐slope protection for the streambanks.
To help ensure tree growth and survival, soil tests may be performed across the Site and amendments
may be applied based on results. Subsoils exposed during construction may be especially difficult for
establishment of vegetation. Soil samples may be taken at grade in the floodplain where soil is
anticipated to be moved during construction.
Additional monitoring and maintenance issues regarding vegetation can be found in Sections 8, 9, and
10 and Appendix 5.
6.8.2 Land Management
The primary purpose of land management prior to construction is to effectively treat invasive plant
populations and to assess soil quality. As detailed below, populations of invasive plants on the Site will
be monitored by Wildlands and treated as necessary both before and during the monitoring period.
Wildlands will also monitor the Site for future land management issues, such as floodplain erosion, bare
areas, and boundary encroachments that arise during the monitoring period.
Exotic invasive species within the conservation easement will be treated using a combination of
different mechanical and chemical techniques. Princess tree (Paulownia tomentosa), wisteria, mimosa,
multiflora rose, and Japanese honeysuckle occur at low densities (< 1%) in the riparian corridor.
Occurrences of Chinese privet will be removed throughout the project, the most extensive and densest
of which is found in the northern portion of the Site. Prior to construction, this monotypic Chinese privet
infestation will be mechanically removed with a mulcher/masticator and cut stump treated with a 25%
triclopyr or glyphosate solution. Outside of the monotypic ‘privet forest’ and where feasible, mechanical
removal of exotic invasives species may take place during construction. Otherwise, exotic invasive plant
species will be controlled using a variety of mechanical and chemical methods based on species, size,
extent, and professional judgement throughout the monitoring period. Multiple treatments are
expected for satisfactory reduction of invasives, especially in the ‘privet forest’ where root sprouts, stem
East Mingo Creek Mitigation Site Final Mitigation Plan
Page 31 June 2023
sprouts, or seed bank release may require follow‐up chemical control. During the floristic inventory
there were incidental observations of several multiflora rose bushes which appeared to have rose
rosette disease (Emaravirus sp.). It is spread by a small mite. If the presence of rose rosette disease is
accurate there may be an element of biological control happening onsite as well. The extent of invasive
species coverage will be monitored, mapped, and controlled as necessary throughout the required
monitoring period. Additional monitoring and maintenance issues regarding vegetation are in Sections
8, 9, and 10 and in Appendix 5.
6.9 Project Risk and Uncertainties
There are no utilities within the project area that require outside maintenance. The streams have been
designed to prevent erosion and headcuts within the stream channel. The stream promotes movement
of sediment through the system from unforeseen inputs or changes within the watershed. As this is a
sandbed system, sediment pulses are expected to move through the system and may periodically
inundate stream channels. This may occur during large storm events (i.e., hurricanes). Channels are
expected to flush out this sediment and reform during subsequent storm events.
The Site is located in a rural watershed where the dominant land uses are agriculture, forest, and
residential. The project parcels and several surrounding project parcels are located in a Voluntary
Agricultural District, according to Johnston County zoning maps. There are currently no developmental
pressures in the area that suggest future changes in land use that might alter the watershed and/or add
stressors to the project.
The easement area will be clearly marked with easement markers along all sides according to standards.
The area of easement along adjacent active grazing pasture will be fenced to exclude cattle access. If
areas not fenced show signs of encroachment or an area is deemed high risk for encroachment, the
easement will be marked with high visibility horse tape between the easement signs. Coordination with
adjacent landowners ahead of project construction will determine if extra marking is necessary to aid in
their agricultural activities. For example, if tall growing crops are planted, six‐foot PVC may be installed
along that boundary.
The streams have been designed to avoid hydrologic trespass on neighboring properties. There is
potential for beaver to move into the Site after construction. If the presence of beaver is identified
onsite, beaver will be trapped and removed from the Site.
Potential maintenance activities that address these risk and uncertainties are located in Appendix 5 –
Maintenance Plan, and Section 10.2 – Long Term Management Activities.
7.0 Determination of Credits
The final stream credits associated with the Site are listed in Table 17. Stream restoration is at a
proposed credit ratio of 1:1. Enhancement II is at a proposed credit ratio of 2.5:1. All riparian buffers are
the required minimum of 50 feet, with most extending beyond the required 50 feet in width to
incorporate riparian wetlands. Wetland re‐establishment and rehabilitation in pasture and wooded
areas containing dense Chinese privet are proposed at credit ratios of 1:1 and 1.5:1, respectively. Within
the forested, cattle‐accessed middle third of the project area, re‐establishment is proposed at credit
ratio of 1.25:1 and rehabilitation at 2:1. All wetland enhancement occurs in the pasture portion of the
Site and is proposed at a 2:1 credit ratio.
East Mingo Creek Mitigation Site Final Mitigation Plan
Page 32 June 2023
Table 18: Project Assets and Credits
Project
Segment
Existing
Footage
or
Acreage
Mitigation
Plan
Footage or
Acreage
Mitigation
Category
Restoration
Level
Priority
Level
Mitigation
Ratio (:1) Comments
East Mingo
Creek Reach 1 3,705 3,837 Warm R 1 1
Full channel restoration,
planted buffer,
permanent conservation
easement
East Mingo
Creek Reach 2 1,167 1,167 Warm EII ‐ 2.5
Cattle exclusion, planted
buffer, permanent
conservation easement
Lizard Creek 83 170 Warm R 1 1
Full channel restoration,
planted buffer,
permanent conservation
easement
Cricket Creek
Reach 1 77 70 Warm EII ‐ 2.5
Cattle exclusion, planted
buffer, permanent
conservation easement
Cricket Creek
Reach 2 ‐ 80 Warm R 1 1
Cattle exclusion, full
channel restoration,
planted buffer,
permanent conservation
easement
Snake Creek
Reach 1 254 250 Warm EII ‐ 2.5
Permanent conservation
easement, cattle
Exclusion
Snake Creek
Reach 2 91 62 Warm R 1 1
Full channel restoration,
planted buffer,
permanent conservation
easement
Deer Creek
Reach 1 241 196 Warm EII ‐ 2.5
Permanent conservation
easement, cattle
exclusion
Deer Creek
Reach 2 125 270 Warm R 1 1
Full channel restoration,
planted buffer,
permanent conservation
easement, cattle
exclusion
Snake Creek
Anabranch 467 250 Warm EII (Not for
Credit) ‐ ‐
Planted buffer,
permanent conservation
easement, cattle
exclusion
Mouse Creek
Reach 1 267 267 Warm EII ‐ 2.5
Permanent conservation
easement, cattle
exclusion
Mouse Creek
Reach 2 134 203 Warm R 1 1
Full channel restoration,
planted buffer,
permanent conservation
easement, cattle
exclusion
East Mingo Creek Mitigation Site Final Mitigation Plan
Page 33 June 2023
Project
Segment
Existing
Footage
or
Acreage
Mitigation
Plan
Footage or
Acreage
Mitigation
Category
Restoration
Level
Priority
Level
Mitigation
Ratio (:1) Comments
Rabbit Creek
Reach 1 228 226 Warm EII ‐ 2.5
Permanent conservation
easement, cattle
exclusion
Rabbit Creek
Reach 2 205 267 Warm R 1 1
Full channel restoration,
planted buffer,
permanent conservation
easement, cattle
exclusion
UT to Rabbit
Creek 27 22 Warm EII ‐ 2.5
Planted buffer,
permanent conservation
easement, cattle
exclusion
Wolf Creek 403 417 Warm EII ‐ 2.5
Planted buffer,
permanent conservation
easement, cattle
exclusion
Lamb Creek
Reach 1 402 268 Warm
EII
(Headwater
Guidance)
‐ 2.5
Permanent conservation
easement, cattle
exclusion
Lamb Creek
Reach 2 308 361 Warm R 1 1
Full channel restoration,
planted buffer,
permanent conservation
easement, cattle
exclusion
Cow Creek 308 302 Warm EII ‐ 2.5
Planted buffer,
permanent conservation
easement, cattle
exclusion
Beaver Creek 318 375 Warm R 1 & 2 1
Planted buffer,
permanent conservation
easement, cattle
exclusion
UT to Beaver
Creek 94 81 Warm R 1 1
Full channel restoration,
planted buffer,
permanent conservation
easement, cattle
exclusion
Wetland Re‐
establishment
1:1
N/A 8.235 Riverine R N/A 1:1
Raise stream channel,
planted buffer, cattle
exclusion, permanent
conservation easement
Wetland Re‐
establishment
1.25:1
N/A 8.408 Riverine R N/A 1.25:1
Raise stream channel,
cattle exclusion,
permanent conservation
easement
East Mingo Creek Mitigation Site Final Mitigation Plan
Page 34 June 2023
Project
Segment
Existing
Footage
or
Acreage
Mitigation
Plan
Footage or
Acreage
Mitigation
Category
Restoration
Level
Priority
Level
Mitigation
Ratio (:1) Comments
Wetland
Rehabilitation
1.5:1
2.668 2.668 Riverine R N/A 1.5:1
Treat invasive species,
planted buffer,
permanent conservation
easement
Wetland
Rehabilitation
2:1
1.506 1.506 Riverine R N/A 2:1
Cattle exclusion,
permanent conservation
easement
Wetland
Enhancement
2:1
10.087 10.087 Riverine RE N/A 2:1
Planted buffer, cattle
exclusion, permanent
conservation easement
Restoration Level Stream Riparian Wetland Non‐Rip.
Wetland
Coastal
Marsh Warm Cool Cold Riverine Non‐Riv.
Restoration 5,706 ‐ ‐
Re‐Establishment 14.961 ‐ ‐ ‐
Rehabilitation 2.532 ‐ ‐ ‐
Enhancement 5.044 ‐ ‐ ‐
Enhancement I ‐ ‐ ‐
Enhancement II 1,274 ‐ ‐
Creation ‐ ‐ ‐ ‐
Preservation ‐ ‐ ‐
Additional Credit
From Extended
Buffers
‐ ‐ ‐
2% Benthic Credit
Adjustment 86.076 ‐ ‐
TOTAL 7,066.076 ‐ ‐ 22.537 ‐ ‐ ‐
8.0 Performance Standards
The stream performance standards for the project will follow approved performance standards
presented in North Carolina Interagency Review Team’s (NCIRT) Monitoring Requirements and
Performance Standards for Compensatory Mitigation in North Carolina (February 2013) and the
Wilmington District Stream and Wetland Compensatory Mitigation Update (NCIRT, October 2016).
Annual monitoring and routine site visits will be conducted to assess the condition of the finished
project by a qualified scientist. Specific performance standards that apply to this project are those
described in the 2016 Compensatory Mitigation Update including Vegetation (Section V, B, Items 1
through 3) and Stream Channel Stability and Stream Hydrology Performance Standards (Section VI, B,
Items 1 through 7). Table 18 summarizes performance standards.
Wildlands proposes growing season dates for wetland hydrology monitoring be March 1st through
November 16th. The growing season for wetland hydrology monitoring will occur during these same
dates each monitoring year. March 1st is proposed as the start date based on observations of soil
temperature exceeding 41 degrees Fahrenheit and bud burst occurring prior to March 1st at numerous
East Mingo Creek Mitigation Site Final Mitigation Plan
Page 35 June 2023
mitigation sites in Johnston and surrounding counties. The NRCS WETS table approximates the growing
season end date as November 16th. Wildlands visually estimated site‐scale leaf color change as a proxy
for leaf senescence. Leaf senescence is primarily controlled by photoperiod, modified by environmental
factors, varies with species, and occurs over a period of several weeks making it difficult to identify a
single date to correlate with the growing season end. The senescence process begins prior to visible
color change; however, color change is readily observable and requires no laboratory procedures or
special equipment (Gill et al. 2015, Mariën et al. 2019). Based on this information, Wildlands
implemented the approach of assuming leaf senescence is occurring on a given site when 50% of the
leaves across that site have changed color. This threshold was generally reached during mid to late
October of 2022 for observed locations in the North Carolina inner coastal plain, which supports the
conclusion that the growing season has ended by November 16. Leaf Senescence was not directly
observed at the East Mingo Mitigation Site. Photo documentation of bud burst, leaf senescence, soil
temperature data, and the WETS table referenced in this section are included in Appendix 1. The
proposed wetland hydroperiod criterion is 12% which is within the hydroperiod range for the Bibb soil
series presented in Table 1 of the Wilmington District Stream and Wetland Compensatory Mitigation
Update (2016).
Table 19: Summary of Performance Standards
Parameter Monitoring Feature Performance Standard
Dimension Cross‐Section Survey
BHR <1.2; ER >2.2 for Restored C/E channels
Enhancement II channels maintain stream channel
geomorphological characteristics; no standards for specific
geomorphological parameter values.
Pattern and Profile Visual Assessment Should indicate stream stability
Photo
Documentation
Cross‐Section Photos
Photo Points
Crossing Photos
No excessive erosion or degradation of banks
No mid‐channel bars, Stable grade control
Crossing photos will be taken at all internal crossings
Hydrology Transducer
Four bankfull events during the 7‐year period in separate years
on East Mingo Creek
30 consecutive days of flow on Lizard Creek, Cricket Creek R1,
Deer Creek R1, Mouse Creek R1, Rabbit Creek R1, Wolf Creek,
Beaver Creek, and UT to Beaver Creek.
Vegetation
(Wetland Planting
Zones, 84% of total
planting area)
Vegetation Plots
MY3 success criteria: 320 planted stems per acre,
MY5 success criteria: 260 planted stems per acre, average of 7
feet in height in each plot. Subcanopy and shrub species will be
disregarded for average height calculations.
MY7 success criteria: 210 planted stems per acre, average of 10
feet in height in each plot. Subcanopy and shrub species will be
disregarded for average height calculations.
Minimum of 4 native species with no single species comprising
more than 50% of stems.
Vegetation (Long
Term Ponded
Areas, 16% of total
planting area)
Vegetation Plots
MY3 success criteria: 265 planted stems per acre
MY5 success criteria: 220 planted stems per acre
MY7 success criteria: 180 planted stems per acre averaging 5
feet in height. 60% herbaceous vegetation coverage or canopy
formed by woody stems.
Wetlands Groundwater Well
Water table within 12 inches of the soil surface for a
consecutive 12% of the growing season (260 consecutive
days). Proposed growing season dates are March 1 through
November 16.
East Mingo Creek Mitigation Site Final Mitigation Plan
Page 36 June 2023
Invasive Species Visual Assessment and
GPS mapping
Invasives cover no more than 5% of the area within the
conservation easement, no kudzu.
Visual Assessment CCPV Signs of encroachment, stream instability, invasive species.
Changes in the channel that indicate a movement toward stability or enhanced habitat include a
decrease in the width‐to‐depth ratio in meandering channels or an increase in pool depth. It is
important to note that pools and bed forms (ripples, dunes, etc.) in sand bed channels may migrate over
time as a natural function of the channel hydraulics. It is also of note that sand bed streams are highly
mobile and movement of the bed material during storm events is not considered a sign of instability.
This could lead to changes in pool depth from storm to storm. These sorts of bed changes do not
constitute a problem or indicate a need for remedial actions. If channel changes indicate a movement
toward stability, remedial action will not be taken. Sand bed streams do not require substrate
monitoring so no pebble counts will be conducted.
Exotic invasive vegetation will be mapped, photographed, and visually assessed annually. Exotic invasive
species will be treated by mechanical and chemical methods so that exotic invasive species percent
coverage does not exceed 5% of the total easement acreage and that there is no presence of kudzu. All
herbicide applications will be performed in accordance with the product label and NC Department of
Agriculture rules and regulations. Benthic data will be calculated but no performance standard will be
defined.
9.0 Monitoring Plan
The Site monitoring plan has been developed to ensure that the required performance standards are
met, and project goals and objectives are achieved.
Project monitoring components are listed in more detail in Table 19. Approximate locations of the
proposed monitoring components are illustrated in Figure 11. Vegetation Plots will cover 2% of the
planted area. In existing forested areas, planting plan areas are approximations based on the limits of
disturbance (LOD). The number of vegetation plots provided in Table 19 assumes that the entire LOD
will be planted. Typically, the entire LOD is not actually disturbed in existing forests and planting the
entire LOD is not required. Wildlands proposes adjusting the number of vegetation plots to sample 2%
of the actual planted area. The actual planted area will be reported in the MY0 report.
Benthic macroinvertebrate sampling will be conducted throughout the lifespan of the project but will
not be tied to performance criteria. Two sampling locations along East Mingo Creek Reach 1 and 2 will
be sampled during pre‐construction, MY3, MY5, and MY7. Sampling will follow the Standard Operating
Procedures for the Collection and Analysis of Benthic Macroinvertebrates (NCDWR, 2016).
Table 20: Monitoring Components
Parameter Monitoring Feature
Quantity by Approach
Frequency Notes
Restoration Enhancement II
Dimension Riffle Cross Sections 8 2 Year 1, 2, 3,
5, and 7 1, 2 Pool Cross Sections 3 N/A
Pattern Pattern N/A N/A 3 Profile Longitudinal Profile N/A N/A
Hydrology Stream Gauge 1 Crest Gauge
3 Flow Gauges 5 Flow Gauges Quarterly 4
East Mingo Creek Mitigation Site Final Mitigation Plan
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Vegetation 100 m2 Plot 18 Fixed, 6 Random Year 1, 2, 3,
5, and 7 5
Wetlands Groundwater Well 14 6
Visual
Assessment 1 Semi‐Annual 7
Benthic
Macro‐
Invertebrates
Qual 4 Sampling 1 1 Pre‐Con, Year
3, 5, and 7 8
Reference
Photos
Stream Photographs 33 Annual
Crossing Photographs 2
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.
2. Entrenchment ratios will be monitored but not provided in annual monitoring reports unless requested.
3. Pattern and profile will be assessed visually during semi‐annual site visits. Longitudinal profile will be collected
during as‐built baseline monitoring survey only, unless observations indicate lack of stability and profile survey is
warranted in additional years. Project streams are sand bed systems; thus, riffles and pools may vary over time.
4. Stream gauges will be inspected and downloaded quarterly. Transducers will be set to record stage once every 2
hours.
5. Vegetation monitoring will follow an IRT approved protocol. The number of vegetation plots was calculated based
on sampling 2% of the anticipated planting area. If the construction disturbance footprint impacts less existing
forest than expected, the actual planting area may be reduced, and the number of vegetation plots may be
adjusted to sample 2% of the actual planted area.
6. Wetland gauges will be inspected and downloaded quarterly. Transducers will be set to record stage once every 6
hours.
7. Locations of exotic and nuisance vegetation along with locations of vegetation damage or boundary
encroachments will be mapped.
8. Benthic sampling will follow the Standard Operating Procedures for the Collection and Analysis of Benthic
Macroinvertebrates (NCDWR, 2016). Sampling will not be tied to performance standards or success criteria. The
2% benthic credit adjustment will be released upon completion of benthic sampling.
10.0 Long‐Term Management Plan
Ownership and Long‐Term Manager
The Site will remain in private ownership (see Appendix 7), protected in its entirety, and managed under
the terms detailed in the conservation easement. Unique Places to Save (UP2Save) will serve as the
Grantee and long‐term manager and will be the party responsible for long‐term management. The
conservation easement will be transferred to UP2Save prior to the initial credit release.
UP2Save is a 501c3 non‐profit organization that is committed to land conservation through sustainable
planning and management. UP2Save has the ability, both logistically and financially, to monitor and
enforce the provisions of the conservation easement and long‐term management plan. The organization
operates in a sustainable manner to facilitate operations well into the future. UP2Save has been
approved to serve as the easement holder and long‐term manager on several mitigation banks in North
Carolina, including Falling Creek Mitigation Site and Box Creek projects. Additional qualifications and
UP2Save’s annual report can be provided upon request.
Long‐Term Management Activities
Prior to the initial credit release and following authorization of the Mitigation Banking Instrument, the
Site will be protected in perpetuity with a conservation easement. Following the issuance of the close‐
out letter (i.e., final determination of success), long‐term management activities will be conducted to
ensure the Site remains perpetually monitored. The long‐term manager will be responsible for
inspecting the Site annually, conducting the long‐term management activities described below, and
rectifying identified deficiencies as necessary. The restrictions and long‐term management
East Mingo Creek Mitigation Site Final Mitigation Plan
Page 38 June 2023
responsibilities will convey with the land, should the property be transferred in the future. The long‐
term manager will be responsible for periodic inspection of the Site to ensure that the restrictions
documented in the recorded easement are upheld.
Table 21: Long‐Term Management
Long‐Term
Management Activity Long‐Term Manager Responsibility Landowner Responsibility
Signage will be installed
and maintained along
the Site boundary to
denote the area
protected by the
recorded conservation
easement.
The long‐term steward will be
responsible for inspecting the Site
boundary and for maintaining or
replacing signage to ensure that the
conservation easement area is clearly
marked.
The landowner shall report damaged or
missing signs to the long‐term manager,
as well as contact the long‐term manager
if a boundary needs to be marked, or
clarification is needed regarding a
boundary location. If land use changes in
future and fencing is required to protect
the easement, the landowner is
responsible for installing appropriate
approved fencing.
Internal easement ford
crossings will be
maintained for
continued stability.
The long‐term steward will be
responsible for inspecting the internal
easement ford crossings and reporting
any stability concerns and/or
maintenance needs to the landowner.
The landowner is responsible for taking
any remedial action regarding crossing
maintenance needs identified by the long‐
term steward.
The Site will be
protected in its entirety
and managed under the
terms outlined in the
recorded conservation
easement.
The long‐term manager will be
responsible for conducting annual
inspections and for undertaking actions
that are reasonably calculated to swiftly
correct the conditions constituting a
breach. The USACE, and their
authorized agents, shall have the right
to enter and inspect the Site and to take
actions necessary to verify compliance
with the conservation easement.
The landowner shall contact the long‐term
manager if clarification is needed
regarding the restrictions associated with
the recorded conservation easement.
Funding Mechanism
Anticipated long‐term management activities and their associated annual cost are listed in Table 21,
below. Wildlands will fund a stewardship endowment that will be managed by UP2Save. UP2Save’s
endowment is designated to provide on‐going revenue to support long‐term management activities. The
stewardship endowment is invested to provide recurring revenue to cover the cost of anticipated annual
activities, easement defense, and violation resolution.
The level of effort for each activity is listed in hours or as a lump sum (LS). The cost per unit or labor rate
and anticipated frequency were utilized to calculate the total and annual activity cost. A conservative
(lower than anticipated) rate of return (or capitalization rate) of 3.50% and the estimated annual costs
of the identified management activities were utilized to determine the endowment funding
requirement.
East Mingo Creek Mitigation Site Final Mitigation Plan
Page 39 June 2023
Table 22: Management Funding
Management Activity Units Hours Cost/Unit Frequency Annual Cost
Annual Monitoring
Staff time for annual planning 44.75
ac 11 $65.00 Annual $715.00
Staff time to address minor violations or issues N/A 10 $650.00 Once per 10
years $65.00
Mileage 100 N/A $0.59 Annual $58.50
Lodging costs 0 N/A $100.00 Annual $0.00
Meal costs 1 N/A $20.00 Annual $20.00
Sign replacement costs 10 N/A $2.00 Annual $20.00
Insurance 1 N/A $100.00 N/A $100.00
Total Annual Funding $840.92
Capitalization Rate 3.50%
Monitoring Endowment $24,026.29
Accepting and Defending Easement in Perpetuity
Staff time for major violations N/A 80 $65.00 N/A $5,200.00
Legal Counsel N/A N/A N/A N/A $10,000.00
Other Incidentals N/A N/A N/A N/A $5,000.00
Stewardship Complexities 1 N/A $5,000 N/A $5,000.00
Monitoring Endowment $25,200.00
Total Monitoring and Legal
Defense Endowment $53,157.14
Rounded $53,157.00
Contingency Plan
Should UP2Save be unable to fulfill the long‐term management responsibilities, a plan to transfer the
responsibilities and stewardship endowment will be presented to the USACE. Long‐term management
responsibilities will not be transferred unless the long‐term manager receives written authorization
from the USACE.
11.0 Adaptive Management Plan
Upon completion of Site construction, Wildlands will implement the post‐construction monitoring
protocols and minor remedial actions (routine maintenance) will be performed as needed for the
duration of the monitoring period. Wildlands, as the Sponsor, will notify the USACE immediately if
monitoring results or visual observations suggest a trend towards instability, major remedial actions are
needed, or that performance standards cannot be achieved. Should major remedial measures be
required, the Sponsor will submit a Corrective Action Plan and coordinate with the USACE until
East Mingo Creek Mitigation Site Final Mitigation Plan
Page 40 June 2023
authorization is secured to conduct the adaptive management activities. The Bank Sponsor is
responsible for funding and/or providing the services necessary to secure any necessary permits to
support the proposed major remedial adaptive management actions, to implement the corrective action
plan, and to deliver record drawings that depict the extent and nature of the work performed. If the
USACE determines that the Bank is not meeting performance standards or the Sponsor is not complying
with the terms of the instrument, the USACE may take appropriate actions, including but not limited to:
suspending credit sales, utilizing financial assurances, and/or terminating the instrument.
12.0 Financial Assurances
Financial assurances will be provided in the form of a Performance Bond for the activities specified in this
plan. The Performance Bond will assure the construction to restore, enhance and/or preserve the
projected aquatic resources. The bond amount will be based on Table 22 below.
Wildlands Holdings VI, LLC (Sponsor) will serve as the Principal, Travelers Casualty and Surety Company
of America (Travelers) will serve as the Surety, and Unique Places 2 Save will serve as the Obligee. As
stipulated in the Performance Bond, the Sponsor shall promptly and faithfully perform the Contract,
according to the terms, stipulations or conditions included in the MBI. However, In the event that the
Sponsor fails to meet the conditions of the Mitigation Plan, Travelers may fulfill these obligations either
by performing those obligations up to the applicable bond amount, or by paying such bond amount to
Unique Places 2 Save who would develop a proposal to fulfill the mitigation obligations.
The Performance Bond will be retired upon approval of the final as‐built report by the DE. Following
retirement of the Performance Bond, a Monitoring Bond will be issued by Travelers, to the Sponsor,
with the UP2Save as the Obligee, to cover anticipated monitoring and adaptive management costs. The
Monitoring Bond will be structured to provide continuous coverage that will decrease in value each year
according to Table 22. An annual Monitoring Bond renewal will be submitted to the USACE upon
approval of each previous year’s monitoring report. The principal amount of the Monitoring Bond is
calculated based on the total estimated costs that remains through closeout, including monitoring and
maintenance activities. Table 22 lists the proposed Monitoring Bond amounts for each monitoring year.
East Mingo Creek Mitigation Site Final Mitigation Plan
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Table 23: Financial Assurances Table
Category 2022‐2024 2025 2026 2027 2028 2029 2030 2031
Engineering $48,000
Legal $7,500
Construction $780,900
Planting $55,000
As‐Built $16,000
Monitoring ‐ $16,000 $16,800 $17,640 $18,522 $19,448 $20,421 $21,442
Re‐Grading
Contingency ‐ $0 $0 $8,000 $0 $0 $0 $8,000
Re‐Planting
Contingency ‐ $1,200 $1,200 $1,200 $1,200 $0 $0 $0
Beaver Control ‐ $0 $0 $1,500 $1,500 $1,500 $1,500 $1,500
Invasive
Treatment ‐ $5,000 $5,000 $0 $2,000 $0 $2,000 $2,000
Easement
Access Control ‐ $750 $750 $750 $750 $750 $750 $750
Corps Admin
Costs $21,744 $3,596 $3,137 $2,662 $2,081 $1,601 $1,167 $674
Sub‐Total $929,144 $26,546 $26,887 $31,752 $26,053 $23,299 $25,838 $34,365
Insurance
Principal $929,144 $194,741 $168,195 $141,307 $109,555 $83,502 $60,203 $34,365
Monitoring Phase Insurance
East Mingo Creek Mitigation Site Final Mitigation Plan
Page 42 June 2023
13.0 References
Conner, William, et al. 2004. Recognizing and Overcoming Difficult Site Conditions for Afforestation of
Bottomland Hardwoods. Ecological Restoration. 22(3): 183‐193.
Doll, Barbara et. al. 2003. Hydraulic Geometry Relationships for Rural North Carolina Coastal Plain
Streams. NC Stream Restoration Institute, Report to NC Division of Water Quality for 319 Grant Project
No. EW20011.
Gill, Allison L., A.S. Gallinat, R. Sanders‐DeMott, A.J. Rigden, D.J. Short Gianotti, J.A. Mantooth, and P.H.
Templer. 2015. Changes in autumn senescence in northern hemisphere deciduous trees: a meta‐
analysis of autumn phenology studies. Annals of Botany 116:875‐888
Hall, S., and T. Howard. 2022. Habitats of North Carolina [Internet]. Raleigh (NC): North Carolina
Biodiversity Project and North Carolina State Parks. Available from:
https://auth1.dpr.ncparks.gov/habitat/index.php.
Mariën, Bertold, M. Balzarolo, I. Dox, S. Leys, M.J. Loréne, C. Geron, M. Portillo‐Estrada, H. AbdElgawad,
H. Asard, and M. Campioli. 2019. Detecting the onset of autumn leaf senescence in deciduous forest
trees of the temperate zone. New Phytologist 224:166‐176
Natural Resources Conservation Service (NRCS), 2011. Web Soil Survey.
http://websoilsurvey.nrcs.usda.gov/app/HomePage.htm
North Carolina Division of Water Resources (NCDWR). 2016. Standard Operating Procedures for
Collection and Analysis of Benthic Macroinvertebrates (Version 5.0).
North Carolina Division of Water Quality (NCDWQ). 2005. Cape Fear River Basinwide Water Quality Plan.
North Carolina Division of Water Quality (NCDWQ). 2011. Surface Water Classifications.
http://portal.ncdenr.org/web/wq/ps/csu/classifications
North Carolina Geological Survey (NCGS), 1985, Geologic Map of North Carolina: Raleigh, North Carolina
Department of Natural Resources and Community Development, Geological Survey Section, scale
1:500,00, in color.
North Carolina Interagency Review Team (NCIRT), 2013. Monitoring Requirements and Performance
Standards for Compensatory Mitigation in North Carolina.
North Carolina Interagency Review Team (NCIRT), 2016. Wilmington District Stream and Wetland
Compensatory Mitigation Update.
North Carolina Wetland Assessment Method. 2016. Prepared by North Carolina Wetland Functional
Assessment Team. Accessed at:
https://files.nc.gov/ncdeq/Water%20Quality/Environmental%20Sciences/ECO/Wetlands/NC%20WAM
%20User%20Man20v5.pdf
Rosgen, D. L. 1994. A classification of natural rivers. Catena 22:169‐199.
Rosgen, D.L. 2001. A stream channel stability assessment methodology. Proceedings of the Federal
Interagency Sediment Conference, Reno, NV, March 2001.
Schafale, M. 2012. Classification of the Natural Communities of North Carolina: Fourth Approximation.
North Carolina Natural Heritage Program.
Shields, D. F., Copeland, R. R, Klingman, P. C., Doyle, M. W., and Simon, A. 2003. Design for Stream
Restoration. Journal of Hydraulic Engineering 129(8): 575‐582.
East Mingo Creek Mitigation Site Final Mitigation Plan
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United States Army Corps of Engineers. 2005. Information Regarding Stream Restoration With Emphasis
on the Coastal Plain. US Army Corps of Engineers, Wilmington District, Regulatory Division And North
Carolina Department of Environment and Natural Resources, Division of Water Quality. Accessed at:
https://files.nc.gov/ncdeq/Water%20Quality/Surface%20Water%20Protection/401/Public%20Notices
/PN_12_05_CoastalPlainSTreamMitigationFinalDraftPolicyNov28.pdf
United States Army Corps of Engineers Routine On‐Site Determination Method presented in the 1987
Corps of Engineers Delineation Manual, the subsequent Atlantic and Gulf Coastal Plain guidance
Sohl, Norman E., and James P. Owens. “Cretaceous Stratigraphy of the Carolina Coastal Plain.” The
Geology of the Carolinas: Carolina Geological Society Fiftieth Anniversary Volume, edited by J. Wright.
Horton and Victor A. Zullo, University of Tennessee Press, 1991, pp. 191–220.Simon, A. 1989. A model
of channel response in disturbed alluvial channels. Earth Surface Processes and Landforms 14(1):11‐
26.
North Carolina Geological Survey (NCGS), 2016. Mineral Resources.
http://deq.nc.gov/about/divisions/energy‐mineral‐land‐resources/north‐carolina‐geological‐
survey/ncgs‐maps/1985‐geologic‐map‐of‐nc, North Carolina Geological Survey (NCGS), 1985. Geologic
map of North Carolina 1:500,000 scale.