HomeMy WebLinkAbout20160849 Ver 1_DRAFT_Prospectus Ver 1.7_FINAL_20160831Upper Rocky Mitigation Bank Draft
Prospectus
Prospectus for Stream and Wetland Compensatory Mitigation Credits
For Yadkin River Basin (CU 03040105)
Prepared by:
4 WATER TEf LAND OLUTION
11030 Roven Ridge Rd, Suite 119, Raleigh, NC 27614
919) 614-5111 1 walerlondsolutions_com
Table of Contents
1 Introduction..........................................................................................................................................1
2 Site Ownership......................................................................................................................................2
2.1 Sponsor/Agent Qualifications.......................................................................................................2
2.1.1 Similar Mitigation Projects in North Carolina and Other States...........................................3
3 Existing Conditions................................................................................................................................6
3.1 Watershed Characterization.........................................................................................................6
3.1.1 South Prong West Branch Rocky River Watershed...............................................................6
3.1.2 Historic Land Use and Development Trends in Project Watershed......................................7
3.1.3 Catchment Areas...................................................................................................................
7
3.2 Pre -Bank Condition of Streams.....................................................................................................8
3.2.1 Existing Channel Geomorphic Characterization....................................................................8
3.2.2 Reach Conditions of Proposed Bank Streams.....................................................................10
3.3 Pre -Bank Condition of Wetlands.................................................................................................16
3.4 Potential Site Constraints............................................................................................................19
3.4.1 Existing easements on the site............................................................................................19
3.4.2 Utility corridors within the site...........................................................................................19
3.4.3 Mineral or water rights issues.............................................................................................19
3.4.4 Hydrologic trespass.............................................................................................................19
3.4.5 Invasive Species...................................................................................................................19
3.4.6 Cultural Resources..............................................................................................................19
3.4.7 Threatened and Endangered Species.................................................................................20
3.4.8 Conditions Affecting Hydrology..........................................................................................20
3.4.9 Adjacent Land Use..............................................................................................................21
4 Proposed Bank Conditions..................................................................................................................22
4.1 Objectives of proposed mitigation bank.....................................................................................22
4.2 Conceptual Mitigation Plan.........................................................................................................22
4.3 Alternative Outcome without Bank............................................................................................24
4.4 Reference Ecosystems................................................................................................................
24
5 Bank Establishment and Operation....................................................................................................25
5.1 Proposed Credit Types................................................................................................................
25
5.2 Credit Release Schedule..............................................................................................................26
5.3 Service Area................................................................................................................................
26
5.4 Proposed Financial Assurances...................................................................................................27
5.5 Long -Term Management............................................................................................................ 27
6 Citations.............................................................................................................................................. 28
Tables
Table 1. Parcel Ownership Information........................................................................................................ 2
Table2. Subwatersheds................................................................................................................................8
Table3. Reach Descriptions..........................................................................................................................9
Table 4. Proposed Stream Mitigation Units (SMUs)..................................................................................25
Table 5. Proposed Wetland Mitigation Units (WMUs)..............................................................................25
Table 6. Credit Release Schedule...............................................................................................................26
Appendices
AppendixA...........................................................................................................................................Figures
Appendix B.......................................................................................................... Historic Aerial Photographs
Appendix C.......................................................................................Options and Landowner Authorizations
Appendix D............................................................................................................. Baseline Monitoring Data
Upper Rocky Mitigation Bank Draft Prospectus
1 Introduction
Water & Land Solutions ("WLS") submits this prospectus for the proposed Upper Rocky Mitigation Bank
("Bank") located in the Yadkin River Basin, Hydrologic Unit Code ("HUC") 03040105. This prospectus was
prepared in accordance with C.F.R. §332.1-8 (2008), Compensatory Mitigation for Losses of Aquatic
Resources, and was based on current District Guidance, which is subject to the approval of the United
States Army Corps of Engineers in consultation with the NC Inter -Agency Review Team (NCIRT). The
purpose of the Bank is to provide stream and wetland mitigation credits to compensate for unavoidable
impacts to Waters of the U.S. authorized under section 401 and 404 of the Clean Water Act, Section 10 of
the Rivers and Harbors Act, and all applicable state statutes.
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Upper Rocky Mitigation Bank Draft Prospectus
2 Site Ownership
WLS submits this prospectus on behalf of URMB, LLC ("Sponsor") forthe proposed Upper Rocky Mitigation
Bank. URMB, LLC is wholly owned by WLS and was established to hold the Bank and conduct all business
regarding the Bank. The point of contact for the Bank is Ashley Abernethy, whose contact info is listed
below:
Ashley Abernethy
11030 Raven Ridge Rd, #119
Raleigh, NC 27614
919-614-5111
ashlev(@waterlandsolutions.com
The Sponsor has options to purchase conservation easements on the JPO Beverly and Mayes Family tract
and is in final negotiations with the owners of the Bjorneboe tracts. The options and agent authorizations
are attached in Appendix C. The property owners for the proposed Bank are listed in Table 1 below.
Table 1. Parcel Ownership Information
12229 Mayes Rd,
Huntersville, NC 28078
00755101
94.5
12001 Mayes Rd,
Huntersville, NC 28078
00714102
59.4
12001 Mayes Rd,
Huntersville, NC 28078
00714106
10.0
18620 Doves Crest Rd,
Cornelius, NC 28031
00712209
41.7
2.1 Sponsor/Agent Qualifications
WLS is a mitigation provider that concentrates on the production and delivery of high quality mitigation
units and services to clients across multiple regions of the United States. WLS was started with the
purpose of combining the key components of high quality and successful mitigation sites, including the
technical expertise for mitigation site development, the understanding of land management, and the
expertise in environmental economics and finance. Through its inception WLS has identified, targeted
and employed some of the most well-respected practitioners in the mitigation industry who have
specifically focused their careers on all of the required aspects and stages of successful mitigation project
implementation. Beyond our focus to improve ecological function of impaired systems, WLS has a specific
mission to positively impact people in our industry and the general public through education, partnership,
and relationship building. In just over two years since establishment, WLS has grown to a staff of eight
people located in Raleigh, NC with satellite offices in Dallas, TX and Huntersville, NC. Individuals making
up the WLS staff have been recognized by our industry colleagues and peers as leaders in the
development, management, design, permitting, construction, and monitoring of mitigation projects. Our
projects and opportunities that we are currently pursuing include projects in North Carolina, South
Carolina, Texas, Virginia, and Ohio.
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Upper Rocky Mitigation Bank Draft Prospectus
2.1.1 Similar Mitigation Projects in North Carolina and Other States
WLS staff have significant experience with stream, wetland, and riparian buffer restoration. Our
staff have been involved with the entire suite of services for hundreds of mitigation projects over
nearly two decades. This experience equates to the successful restoration of hundreds of
thousands of feet of stream and thousands of acres of wetlands. Several project examples are
highlighted below:
Monteith Park Mitigation Site, Charlotte/Mecklenburg Stormwater Services, Huntersville, NC
Monteith Park before (left) and one year after restoration (right)
WLS is currently managing the successful completion of what is considered to be one of the most
unique watershed restoration projects in the mitigation industry. The Monteith Park Mitigation
Site (MPMS) is the only project to date in North Carolina that utilized a watershed restoration
approach to generate additional mitigation credits at ratios beyond those typically awarded for
stream and wetland restoration credits with the intent on properly funding full restoration
activities. The MPMS was identified as one of the highest ranked stream restoration reaches in the
McDowell Creek Watershed of Mecklenburg County, NC. The project involved the Rosgen Priority
Level I restoration of 3,550 linear feet of stream, 1.0 acre of wetland restoration, and the retrofit
design and installation of five Stormwater Control Devices (bioretention basins) in an attempt to
restore watershed hydrology to predevelopment conditions.
WLS staff identified the project in 2008 and have led project management duties on all aspects of
the project throughout its entirety. Mr. McIntyre led resource agency coordination, including the
combination of Mecklenburg County, City of Charlotte, NCDWR, and USACE guidance and protocols
to negotiate the additional credit ratios and associated values for the project. Mr. McIntyre led
conceptual planning and assisted in the design of the mitigation project. Ms. Abernethy was the
financial manager and construction manager for the project (completed in July 2014) and has also
led efforts to develop stream/wetland restoration and environmental education for the Monteith
Park Community Residents. This complex mitigation project continues to be a highly successful
example of how ecosystem restoration, that involves technical, legal, financial, political, and
educational aspects, can be implemented in rapidly developing watersheds.
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Upper Rocky Mitigation Bank Draft Prospectus
Spindletop Bayou Mitigation Bank, Liberty and Chambers County, TX
Spindletop Bayou in
wetland restoration
mitigation bank site
likely occur in 2018.
WLS is currently partnered with Ecosystem
Renewal and EcoGenesis on a wetland and
stream mitigation bank in Liberty County and
Chambers County, Texas. The proposed 460 -
acre bank site will restore over 400 acres of
riparian and non -riparian wetlands and 10,000
linear feet of 1st order headwater streams. The
proposed property has been highly impacted by
agricultural practices (rice and sorghum
production) since the 1930's. This project will
provide significant uplift to aquatic and
terrestrial habitats as well as water quality
improvements to Spindletop Bayou.
WLS has led coordination efforts with the
volves over 400 acres of USACE-Galveston District IRT, assisted in the
and 10,000 If of stream overall credit assessment, determination, and
generation, and full restoration design of the
The proposed design was finalized in the winter of 2016 and construction will
Cedar Bayou Mitigation Bank, Liberty County, TX
WLS is currently working with Ecosystem Renewal
and EcoGenesis on a wetland and stream
ecosystem mitigation bank in Liberty County,
Texas. WLS is providing the lead technical services
for the development of the Cedar Bayou
Mitigation Bank (CBMB). The proposed 1100 acre
mitigation bank will provide over 900 acres of
restored wetlands and 21,000+ linear feet of 1st
order and 2nd order headwater stream in the
Western Gulf Coastal Plain Ecoregion of the
Galveston USACE District. This Upper Coastal Plain
ecosystem will provide a complex mix of diverse
habitats including multiple wetland types actively
integrated with the headwater stream system. Due to over a century of agricultural practices on hard pan
clay soils, this region experiences high flood frequency during large precipitation events. WLS will utilize
a combination of priority I and priority II approach to maximize ecological uplift while creating sufficient
flood storage capacity for large precipitation events in what is expected to be the next high growth area
for the Houston region. The project design will be finalized in 2016 with construction scheduled for 2018.
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Edwards Mitigation Sites, Johnston County, NC
The Edwards Sites (Sites) are three separate
restoration projects located adjacent to each other
and within the same watershed that are being
developed under the NCDMS Full Delivery
Program. The Sites present a unique and exciting
opportunity for the restoration of an entire
subwatershed that has been highly impacted from
agricultural practices for over a century. The Sites
are 3 of 5 potential restoration projects being
developed by WLS, all located adjacent to one
another, that will successfully restore/enhance
over 22,000 linear feet of stream and will
permanently protect approximately 64 acres of riparian buffer corridor within a watershed that is
expected to see widespread land use conversion from agriculture to suburban sprawl. The Sites have
been negatively impacted by cattle grazing and row crop production since the 1950's. In addition, a
portion of the streams have been impacted due to impoundments. Nearly all vegetated buffers along the
stream reaches have been removed for agricultural practices. Wetlands were historically present
throughout the riparian corridor, but have been significantly impacted due to cattle trampling and channel
incision (draining wetland areas). Most of the primary stream systems have been channelized and incised
(through headcut migration) leading to a significant loss of biologic function for the entire watershed. The
comprehensive restoration of this subwatershed will provide significant habitat and water quality
improvements to the on-site wetlands, streams, and riparian buffers as well as the downstream
watershed.
Upper Rocky Mitigation Bank Draft Prospectus
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Upper Rocky Mitigation Bank Draft Prospectus
3 Existing Conditions
The proposed Bank is located in Mecklenburg County, North Carolina in the Yadkin River Basin (Upper
Rocky River), Hydrologic Unit Code ("HUC") 03040105. The Bank centroid is located at 35.459622°, -
80.829787° (Figure 1). The Bank is adjacent to William Hough High School in Huntersville, NC.
To reach the site from 1-85:
1. Take EXIT 55, NC -73 West towards Huntersville
2. Continue on NC -73 for approximately 9 miles. Turn RIGHT onto Mayes Road.
3. Turn RIGHT onto Barnhart Road/Bailey Road.
4. The Bank is approximately 1 mile on the left, directly adjacent to William Hough High School.
The proposed Bank will protect approximately 43 acres in a permanent conservation easement. The
easement is located on four parcels, which are used for residential and agricultural purposes. The first
parcel is currently being subdivided and developed into single family homes on approximately 0.25 acre
lots; 40 homes are slated for the proposed development. The easement will run through the open space
reserved for this development. The second parcel contains a single family home, row crops, and non -
timbered forest. The third parcel is currently in timber. The fourth parcel contains a single family home.
3.1 Watershed Characterization
3.1.1 South Prong West Branch Rocky River Watershed
The headwaters of the Rocky River are separated into three primary subwatersheds: the South Prong
West Branch Rocky River Watershed, the West Branch Rocky River, and the Upper Rocky River Watershed.
The South Prong West Branch Rocky River Watershed, where the Bank is located, includes the northern
portion of Mecklenburg County and includes portions of the Towns of Cornelius, Davidson, and
Huntersville, North Carolina. The South Prong West Branch of the Rocky River joins with the West Branch
Rocky River to the East of Hopewell, NC. The West Branch Rocky River joins with the Rocky River less than
two miles downstream of this confluence along the Mecklenburg and Cabarrus County line. The Rocky
River is part of the Yadkin River Basin and joins with the Yadkin River in Cabarrus County.
The Bank is located within the South Prong West Branch Rocky River Watershed, one of the fastest
growing regions in North Carolina. According to the draft Rocky River Watershed Management Plan
(Mecklenburg County Storm Water Services 2010), the construction of the 1-77 corridor through this
region resulted in a significant increase in land development activities with South Prong of the Rocky River
experiencing the biggest increase in growth. The Rocky River and its tributaries have been listed on the
2014 303(d) list for copper, turbidity, and impaired biological integrity (EPA 2014). In addition to these
parameters, a Total Maximum Daily Load (TMDL) for fecal coliform was added to the list of water quality
concerns with this upper watershed. Portions of the South Prong Rocky River have been straightened and
dredged, likely for flood control. Channel straightening, significant channel incision and excessive
sedimentation from stormwater runoff are evident throughout the entire watershed. The upper
watershed surrounding the Bank has seen substantial land use change from agriculture to residential and
municipal development over the past five years. Land use changes, excessive stormwater inputs, and
physical changes to surface waters in the watershed have caused degradation in water quality through
excess sedimentation. Mecklenburg County Storm Water Services (MCSWS) has outlined a watershed
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Upper Rocky Mitigation Bank Draft Prospectus
plan (2010) highlighting current efforts to improve water quality through stream and wetland restoration
and stormwater improvements. MCSWS has prioritized parcels and streams for restoration in which the
South Prong West Branch of the Rocky River is included. Because of the position of South Prong West
Branch of the Rocky River in the upper headwaters, restoration of this system along with the first order
tributaries can produce significant improvements in downstream water quality.
3.1.2 Historic Land Use and Development Trends in Project Watershed
A historical aerial review from 1948 to present (Appendix B) was conducted to assess landscape changes
in the South Prong West Branch of the Rocky River watershed. Prior to the development of the Bailey's
Glen community and William Hough High School (within the past 5 years), the land within this watershed
was primarily forested but heavily utilized for agriculture since the early 1900's. A review of historic aerials
indicates that from 1948 through 1983, the watershed experienced few land use changes with the
exception of possibly less land being utilized for row crop and/or pasture. In the 1948 aerial, there
appeared to be a substantial forested buffer surrounding the majority of the South Prong West Branch of
the Rocky River. By 1965, much of the forested buffer around South Prong West Branch of the Rocky
River appears to have been modified through timbering activities, but still remained largely development
free. In discussions with the current landowners along the south side of the South Prong West Branch of
the Rocky River, these properties were utilized for various agricultural uses included timber production,
cattle grazing, and row crops. The entire watershed remained almost entirely void of impervious surfaces
until around 2003. Between 2003 and 2008, development projects including Bailey Middle School and a
local town park were constructed along Bailey Road. Starting in 2009 and continuing to date, the three
largest impervious projects were constructed, which included William Hough High School, Bailey's Glen
residential development, and the upcoming Beverly development. These projects combined changed the
upper watershed impervious coverage from less than 2 percent to approximately 20 percent. It is
anticipated that similar development projects will eventually occur on the remaining undeveloped
proportions as Mecklenburg County continues to grow, having a continued impact on the watershed and
further supporting the need for the proposed bank.
3.1.3 Catchment Areas
The evolution of the land use within the South Prong West Branch of the Rocky River watershed from a
combination of forested and agricultural to the present day medium density combination of residential
and municipal has altered watershed characteristics. Figure 2 illustrates the watershed delineation,
dividing the watershed into 7 catchment areas based on reach designation. To date it does not appear
that that majority of the catchment areas have been significantly disturbed as catchments 4, 5, 6, and 7
still remain largely undeveloped. Catchments 1 and 3 have been significantly altered while catchment 2
and portions of catchment 4 are currently being developed. In addition, because the watershed still
consists of large land tracts that will at some point be developed, the watershed hydrology changes will
continue. Watershed hydrology, and specifically infiltration patterns, play a critical role in influencing the
physical characteristics and ecological health of stream ecosystems. Stream flow magnitude, frequency,
duration, and timing are major driving forces that control the physical and ecological conditions of stream
corridors. At the downstream easement boundary of the Bank project, the South Prong West Branch of
the Rocky River currently receives flow from an area of approximately 856 acres (1.34 sq. miles). Table 2
shows total area of the catchments and total approximate impervious area for the entire watershed.
Currently, the total impervious surface area within the South Prong West Branch of the Rocky River
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Upper Rocky Mitigation Bank Draft Prospectus
watershed is approximately 20 percent. Five catchment areas have little to no impervious surface area
while the remaining two catchment areas contain dense residential development and impervious areas
ranging from 29 to 56 percent.
Table 2. Subwatersheds
155.2
39%
R1
61.8
7%
R2
206.0
56%
R3
62.0
<1%
R4
R5 (R5a &
113.0
<1%
R5b)
R6 (R6a &
101.3
<1%
R6b), R7,
R8
48.3
<1%
R9
37.2
49%
R10
856.1
20%
3.2 Pre -Bank Condition of Streams
3.2.1 Existing Channel Geomorphic Characterization
North side of Rocky River has extensive
impervious coverage (high school)
currently being treated by existing
stormwater BMP's. South side of Rocky
River is currently being developed.
Has been mostly timbered in preparation
of residential development, no current
impervious coverage aside from Bailey
Road.
Highly impacted subwatershed due to high
density residential development. Minimal
stormwater detention.
Mostly forested, no current impervious
coverage aside from a single family home.
Mix of forested and agricultural conditions
(row crop), no current impervious
coverage aside from 2 single family homes.
No current impervious coverage. Timber
and agricultural activity has dominated this
upper watershed for nearly a century.
Mix of forested and timbered conditions,
no current impervious coverage aside from
a single family home.
Highly impacted subwatershed due to
medium density residential development.
Minimal stormwater detention.
WLS field crews conducted a rapid geomorphic assessment of the South Prong West Branch of the Rocky
River watershed to assess all streams and wetlands within the project reach. This assessment was focused
on channel erosion, stream stability, and the impact of past and current land use practices on the Banks
natural resources. Jurisdictional stream criteria were evaluated according to the North Carolina Stream
Classification Method (NCSAM), version 4.11 (2010). Field observations for stream assessments included
sediment supply and transport, channel boundary material properties (bed and bank), vegetation
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Upper Rocky Mitigation Bank Draft Prospectus
characteristics, evidence of excessive channel erosion, and overall channel stability. Where excessive
erosion occurred, observations noted the mechanism of failure, whether the instability was localized or
reach wide, and if the failure was recently active or historical. Table 3 provides reach designation stream
length, approximate drainage area, and general description.
Table 3. Reach Descriptions
Water & Land Solutions Page 9
Severe incision, actively eroding banks,
1,846
794
straightened
Moderate incision, actively eroding banks,
711
62
sedimentation from upstream development, lack
of vegetated buffers
Severe incision, actively eroding banks,
1,369
206
straightened
Collapsed culvert, severe incision, straightened,
614
62
spoil piles present on banks
Moderately incised to severely incised, active
3,614
220
head cuts, severe sedimentation
Moderate incision to low incision, upstream
portion (above headcut) shows little to no
1,015
102
impairment, below active headcuts begins
moderate incision
1,176
102
Braided, wetland complex, no impairment
835
2
Single -thread wetland complex, no impairment
800
8
Severe incision, straightened
129
37
Severe incision
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Upper Rocky Mitigation Bank Draft Prospectus
3.2.2 Reach Conditions of Proposed Bank Streams
3.2.2.1 Reach 1
Reach 1 is designated as the lower reach of the South
Prong West Branch of the Rocky River at the terminus of
the Bank starting immediately upstream of the Bailey
Road bridge crossing (approximately 1,846 linear feet).
Cross section 1 was recorded for Reach 1. Reach 1 has a
total drainage area of 794 acres with a total watershed
impervious coverage of 29 percent. This reach is highly
unstable and incised and appears to have been
straightened and possibly dredged at some point in the
past. Because of land use activities (agricultural), it is
possible the stream was relocated closer to the northern
edge of the valley. Stream banks are highly unstable and
in -stream habitat is under constant duress due to
upstream bank erosion. The channel banks are highly
incised with elevations of up to 12 feet, totally removing
floodplain access. Based on NCSAM, this stream system is
classified as low and is therefore considered to be low
quality.
3.2.2.2 Reach 2
Reach 2 is a tributary to the South Prong West Branch of
the Rocky River flowing to the northwest and originating
southeast of Bailey Road (immediately upstream and
offsite). The stream maintains an existing length of 711
linear feet within the Banks easement boundaries. This
perennial tributary was in relatively stable condition prior
to land use changes within the past year. However, with
the construction along Bailey Road and clearing for future
development in the upper watershed of this tributary, the
stream within the Banks easement limits has been
impacted by sedimentation and most recently in -stream
bank erosion. Some vegetation clearing along the stream
banks for the future crossing into the Beverly subdivision
has removed trees that had historically provided bank
stability. Reach 2 contains cross section 2 and has a total
catchment of 62 acres with a total watershed impervious
coverage of 7 percent. However, watershed conditions
are changing rapidly for this channel which will lead to
continued bank failure, incision, and habitat loss. Based
on NCSAM, this stream system is classified as low and is
therefore considered to be low quality.
Page 10 4
3.2.2.3 Reach 3
The South Prong West Branch of the
Rocky River splits into three primary
channels as the stream complex
transitions upstream. Reach 3 is the
northern most channel which flows
close to the northern boundary of
the Bank conservation easement and
eventually upstream into the Bailey's
Glen residential community. This
channel was historically relocated to
the outer edge, and is slightly
upslope of its natural valley. Within
the Bank limits, this reach is
approximately 1,369 linear feet and
has a drainage area of approximately
206 acres. This channel currently has
three significant headcuts that continue to move upstream and have caused significant sedimentation
downstream. While this reach is flanked by a mature hardwood buffer, the current headcuts and
substantial incision create a detachment between the streamflow and relict floodplain. Stream banks are
highly unstable and in -stream habitat is mostly nonexistent. Cross sections 3, 4, and 5 were collected for
Reach 3 to accurately depict the presence and impacts of these 3 headcuts. Based on NCSAM, this stream
system is classified as low and is therefore considered to be low quality.
Upper Rocky Mitigation Bank Draft Prospectus
3.2.2.4 Reach 4
Reach 4 is a tributary to the South Prong West Branch of
the Rocky River flowing from the south and continuing
upstream off of the Bank property. Within the Bank
property, this stream was historically straightened and
dredged, likely for farming and/or flood control
purposes. Bank height ratios are extremely high
indicating a very unhealthy system. Reach 4 has an
existing culvert crossing for a relict driveway (soil road).
Upstream (outside the Bank limits) of this culvert the
stream remains in stable condition and was not
historically straightened or dredged. Downstream of
this culvert, and within the Bank limits, the stream
exhibits significant incision, nearly complete habitat
loss, and excessive bank erosion. The floodplain
maintains a hardwood buffer but the stream cannot
access its relict floodplain unless under extreme
precipitation conditions. The approximate length of
Reach 4 within the Bank property is 614 linear feet and
the drainage area is approximately 62 acres. Cross
section 8 was taken downstream of the culvert crossing
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Upper Rocky Mitigation Bank Draft Prospectus
in the highly incised and unstable section while cross section 9 was taken upstream of the culvert where
the channel maintains stability. The upstream portion of Reach 4 maintains a relatively stable dimension,
pattern, and profile and will provide a reference reach for design on the Bank portion of reach 4. When
scored based on NCSAM, the lower reach of this stream system was classified as low quality.
3.2.2.5 Reach 5 (including 5A & 5B)
Reach 5 is the southernmost
branch of the South Prong West
Branch of the Rocky River and
originates from the confluence of
two intermittent channels within a
relatively undeveloped drainage
area. The Bank stream length for
this reach is approximately 3,614
linear feet and the drainage area is
approximately 220 acres. Reach 5
included a primary channel and
three small tributaries. As this
reach transitions into the
confluence valley where it
connects with the two other Upper
Rocky River branches, the channel&IA
.:
& £ y
has been pushed against the edge
of the valley and straightened, maintaining a ditch -like dimension, pattern, and profile. Excessive
sedimentation from upstream erosion has settled out in this portion of the reach and the channel
maintains a uniform and unnatural habitat condition (no riffle/pool complex). As reaches transition
upstream and away from the deposition in the valley containing the confluence, the channel exhibits
significant incision, overall habitat loss, and excessive bank erosion. The channel does appear to be within
its natural valley and historic pattern, but the incision is significant enough that the channel likely does
not access its floodplain unless under extreme precipitation conditions. While some short sections of this
reach indicate a building bankfull bench, because of the incision these short sections are overwhelmed
during storm events and a consistent dimension and profile are unattainable without restoration. The
channel contains multiple headcuts indicating a constant presence of instability. Cross section 11 was
recorded along Reach 5 and verifies high bank height ratios as well as sever incision. Based on NCSAM,
this stream system is classified as low quality.
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3.2.2.6 Reach 6 (including 6A & 68)
Reach 6 is the central branch of the South Prong West
Branch of the Rocky River. Reach 6 represents the
transition between the upstream braided multi -thread
Reach 7 (described below) and the highly incised
downstream Reach 1. Because of significant modifications
to this valley for historic agricultural practices, it is
relatively difficult to discern where the historical location
of this channel should be. A series of small disconnected
ditches, sediment depositional areas, and other areas of
stormflow during large precipitation events indicate a
consistently changing and unstable valley. Reach 6 has a
series of headcuts that have moved upstream from Reach
1 and Reach 5. Cross sections 10, 12, and 13 were recorded
to capture the varying degrees of incision and headcut
transition throughout this reach. The stream length of
Reach 6 within our Bank area is approximately 1,015 linear
feet while the drainage area encompasses approximately
102 acres.
Upper Rocky Mitigation Bank Draft Prospectus
Some portions of Reach 6 located above the series of headcuts maintain what appears to be a stable
dimension, pattern, and profile and have access to the floodplain during precipitation events. The areas
of Reach 6 that are not incised also contain the presence of adjacent wetlands, providing a snap shot of
what this watershed looked like prior to stream modification. The forested buffer is relatively young and
is dominated by more successional species indicating past timber and agricultural activities. When the
stream is classified overall based on NCSAM, this stream system is classified as low and is therefore
considered to be low quality.
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Upper Rocky Mitigation Bank Draft Prospectus
3.2.2.7 Reach 8
Reach 8 is immediately upstream of Reach 7 and continues as
the central branch of the South Prong West Branch of the
Rocky River. Reach 8 is the same stream system as Reach 7
but is distinctly different in that it represents the transition
upstream and out of the stable multi -thread braided stream
and wetland complex. The valley slope surrounding Reach 8
appears to be slightly steeper and more typical of the
Piedmont than Reach 7. Beaver activity continues to be
active within Reach 8 but because of the change in valley
conditions the beaver dams have less impact on the adjacent
floodplain. Stream conditions within Reach 8 are similar to
open water systems (ponding). The stream remains incised
and does not maintain a riffle/pool complex because of
ponding. Sedimentation from upstream bank erosion gets
stored in Reach 8 and water quality conditions are not
indicative of a perennial Piedmont stream. Stream length of
Reach 8 within the Bank limits is approximately 835 linear
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Upper Rocky Mitigation Bank Draft Prospectus
feet and an upstream catchment acre of approximately 82 acres. Based on NCSAM, this stream system is
classified as high and is considered to be high quality.
3.2.2.8 Reach 9
Reach 9 is a tributary to the central branch of the South
Prong West Branch of the Rocky River flowing from the
south. Within the Bank property, this stream likely was
historically straightened and dredged. This reach is
severely incised and exhibits bank erosion and instability.
The Bank stream length for this reach is approximately 800
linear feet and the drainage area is approximately 48
acres. Excessive sedimentation from bank erosion has
settled into riffles and pools creating a uniform and
unnatural habitat condition. The channel does appear to
be within its natural valley and historic pattern, but the
incision is significant enough that the channel does not
access its floodplain unless under extreme precipitation
conditions. Cross section 14 was recorded along Reach 9.
Based on NCSAM, this stream system is classified as low
and is considered to be low quality.
3.2.2.9 Reach 10
Reach 10 is a short tributary to the South
Prong West Branch of the Rocky River
(Reach 1) flowing from the north along
the west side of William Hough High
School. The valley for Reach 10 is
moderately defined but the channel
appears to have a head cut from Reach 1
moving upstream off of the Bank
property due to the incised condition of
Reach 1. This reach is severely incised
and exhibits bank erosion and instability.
The Banks stream length for this reach is
approximately 129 linear feet and the
drainage area is approximately 37 acres.
It is unclear if this reach had formed a
perennial stream prior to headcutting from Reach 1. The channel does appear to be within its natural
valley and historic pattern, but the incision is significant enough that the channel cannot access its
floodplain unless under extreme precipitation conditions. Cross section 15 was recorded along Reach 10.
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Upper Rocky Mitigation Bank Draft Prospectus
3.3 Pre -Bank Condition of Wetlands
The historical presence of wetlands in Piedmont North Carolina, specifically within the Mecklenburg
County region, was largely concentrated within headwater stream valleys that had sufficiently sized
watersheds, high clay content in soils, and smaller streams that maintained relatively frequent overbank
flooding. These riparian wetland systems were dependent upon these specific conditions in order to
maintain consistent hydrology that defines jurisdictional wetlands. As agricultural practices spread
throughout this region in the early to mid -1900's, streams were straightened, dredged, and/or relocated
in order to maximize agricultural production. These historically wet valleys provided ideal settings for
high crop yield and cattle production because of access to groundwater. Stream modifications and
subsequent drainage of the floodplain provided the greatest factor for the general loss of Piedmont
riparian wetlands during this time period. As the urban growth of Charlotte increased and the suburban
growth followed, these already impacted systems underwent additional major watershed hydrologic
changes including increased stormflow velocities and quantities (associated with an increase in
impervious surface) which led to increased downcutting of streams. The urban/suburban growth mixed
with the historical agricultural practices led to a significant loss of Piedmont wetlands in the Mecklenburg
County region.
The Bank site represents this combination of conditions due to
the agricultural land use practices during the last century and
now suburban growth occurring within the watershed. The
combination of the three major stream reaches coming together
at their confluence within a low slope valley, which also containsW.
,
a high clay content, can lead to the conclusion that it is highly `
likely that the entire valley maintained wetland conditions prior
to agricultural land use activities. In the few areas of the Bank
where streams are not incised, wetland pockets are abundant. a r.
In the areas downstream of current and active headcuts where x
streams have been actively draining floodplain soils, wetland F'
vegetation indicators are present but the lack of hydrology has
led to a significant loss of wetlands. The entire Bank valley was
i
mapped by a licensed soil scientist as Monocan soils, one of only I
two soils mapped in Mecklenburg County that maintain riparian
wetlands. Based on the combination of high clay content soils,
abundant surface water, and the presence of wetlands where stream incision isn't present, it appears as
if the majority of the valley should maintain jurisdictional wetlands. A full soils investigation has been
conducted by a licensed soil scientist and results are pending.
On-site wetlands were identified using the three -parameter approach prescribed in the 1987 Corps of
Engineers Wetlands Delineation Manual. Jurisdictional wetlands were also evaluated according to the
North Carolina Wetland Assessment Method (NCWAM), version 4.1 (2010).
Based on our assessment of the on-site water features, there are six wetlands identified within the Bank
boundaries (Figure 6). A total of approximately 282,000 square feet (6.5 acres) of wetlands were
delineated using pink and black striped and blue sequentially numbered flagging.
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Upper Rocky Mitigation Bank Draft Prospectus
The first wetland system (W1 in Figure 6) is the most upstream wetland within the Bank property and is
located along Reach 8. This system is dominated by a series of larger active beaver dams that appear to
be actively expanded and maintained by the current beaver population. Vegetation within this system is
dominated by more upland and floodplain species not typically found within wetlands. Vegetation
mortality within this wetland appears high as more upland species adjust to the rising water surface
elevation due to the beaver activity. This system functions more like an open water pond and is not
expected to maintain significant wetland conditions once the restoration of the valley and stream occurs
(including beaver removal). Based on NCWAM, this wetland system is classified as low quality.
The second and most dominant jurisdictional wetland system (W2 in Figure 6) is the largest wetland
identified within the Bank property and is located along Reach 7 (multi -thread stream and wetland
complex). This system is located immediately downstream of Wetland System 1 and is differentiated by
the lack of active beaver, vegetation composition, saturation pattern, and valley slope conditions. This
system is dominated by a series of small relict beaver dams that have naturalized over the past
approximately 50 years. While beavers are currently active upstream of this system, it does not appear
that beavers actively build or maintain within this wetland area based on site conditions. This wetland is
located within an area of relatively low valley slope as compared to typical Piedmont stream valleys, likely
due to historic deposition from upstream bank erosion. The valley has been mapped as Monacan soils.
The low slope valley condition, presence of historic beaver activity, mapped hydric soils, and stable
streams (no headcuts present) allow this wetland to maintain a very consistent and strong presence.
Vegetation within this system is dominated by herbaceous and shrubs including juncus effusus, carex spp,
and scirpus sp. This wetland maintains saturation throughout the year and provides significant water
quality benefits. This system is surrounded on both sides by a relatively steep terrain. Based on NCWAM,
this wetland system is classified as low quality; however the low rating was likely due to the historic impact
of beavers as the wetland system is currently considered a high quality functioning system.
The third wetland (W3, Figure 6) is directly downstream and connected to System 2. However, this system
is significantly different than System 2 because of multiple factors. System 3 is located in the confluence
valley where all three of the major Upper Rocky River tributaries join creating a valley that likely remains
saturated during and immediately following precipitation events under stable conditions. System 3
wetland boundaries were delineated above the active stream headcuts where this consistent soil
saturation occurs. This system is forested and functions like a bottomland hardwood. Based on NCWAM,
this wetland system is classified as high and is considered to be a high quality wetland system. The
northeastern wetland boundary (downstream wetland edge) coincides with the headcut locations along
the three tributaries, indicating the impact of wetland hydrology loss relative to stream incision. As
stream base flow lowers due to stream incision, the groundwater elevation is directly lowered and
therefore wetland hydrology is not present long enough during the growing season to maintain wetland
conditions. Soil conditions and vegetation conditions remain consistent throughout the entire
downstream valley. It should be noted that as the stream incision gets deeper and groundwater
elevations lower in response, the presence and density of Chinese Privet significantly increases becoming
the dominant species within this community, which is common of drained floodplains in the Piedmont.
The fourth wetland (W4, Figure 6) pocket is located downstream of the confluence valley along the outer
edge of the Reach 1 floodplain. This small wetland pocket represents a snap shot of what the floodplain
edge of the South Prong West Branch of the Rocky River likely contained prior to significant land use
changes over the past century. The majority of the floodplain of the South Prong West Branch of the
Water & Land Solutions Page 17
Upper Rocky Mitigation Bank Draft Prospectus
Rocky River has been drained by straightening, dredging, and headcutting of on-site streams. In addition
to these activities, a lateral ditch was dug along the toe of slope of the floodplain to drain what was likely
wetland conditions. Wetland System 4 represents the only area outside the effectively drained portions
of the floodplain (by this ditch/stream network). This small wetland pocket is classified as a riparian toe -
of -slope wetland and historic hydrology is directly linked to base flow conditions within the South Prong
West Branch of the Rocky River, as well as rising groundwater where the natural site valley slopes meet
the floodplain. This system is forested and functions like a bottomland hardwood wetland. Based on
NCWAM, this wetland system is classified as medium quality. While he system functions as a high quality
wetland, the loss of overbank and overland flooding from incised streams within the floodplain doesn't
allow this weltand to meet its maximum NCWAM value.
The fifth wetland (W5, Figure 6) is located upstream of the confluence valley along Reach 5. This wetland
system is a combination of wetland pockets that maintain very similar conditions to wetland Systems 3
and 4. These wetland pockets are riparian wetlands along the toe of the valley slope and are directly
linked to base flow conditions within the stream. The majority of Reach 5 is severely incised and unstable.
Where this incision occurs, the floodplain and historic riparian wetlands have been drained. However, a
small section of Reach 5 remains in stable condition due to a significant root structure that has allowed
the stream headcut to be avoided. The riparian wetland pockets associated with wetland system 5 are
adjacent to this short section of stable stream, further indicating that if the streams are restored to their
proper elevation, wetland pockets are anticipated to form throughout the floodplain. This system is
forested and functions like a bottomland hardwood. Based on NCWAM, this wetland system is classified
as high quality.
The sixth wetland (W6, Figure 6) is located along
` Reach 5 as this stream enters confluence valley.
This wetland system maintains very similar
conditions to wetland systems 3 and 5. This
forested riparian wetland is within an area of
historic deposition along Reach 5 where
sediment from upstream bank erosion has
settled out creating a backwater effect to some
degree. The majority of Reach 5 upstream of
this wetland is severely incised and unstable.
However, the stream adjacent to wetland 6
maintains a shallow dimension allowing
frequent overbank flooding and wetland
hydrology to persist within the floodplain. The riparian wetland system 6 provides further evidence that
if the streams are restored to their proper elevation, wetland pockets are anticipated to form throughout
the floodplain. This system is forested and functions like a bottomland hardwood. Based on NCWAM,
this wetland system is classified as high quality with the only negative factor being sediment flushing that
occurs within due to continued upstream bank erosion.
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Upper Rocky Mitigation Bank Draft Prospectus
3.4 Potential Site Constraints
3.4.1 Existing easements on the site
Portions of Reach 3, 5, and 6 are located on property that is managed under a Wildlife Habitat
Conservation Agreement. This Agreement did not require recordation of a conservation easement. WLS
has coordinated with NC Wildlife Resources Commission to ensure that this land designation is compatible
with stream and wetland restoration projects.
There are no other existing easements on the site.
3.4.2 Utility corridors within the site
The proposed Bank site contains a sewer right of way that runs parallel to Reach 1 along the northern
Bank boundary. There are three instances where the sewer line will cross the restored Reach 1. These
right-of-ways will be excluded from the conservation easement and credit calculations. The presence of
this sewer utility will not negatively impact the proposed project.
There are no other existing utility corridors on the site.
3.4.3 Mineral or water rights issues
There are no mineral or water rights issues within or adjacent to the proposed Bank.
3.4.4 Hydrologic trespass
The downstream portion of Reach 1 is located within a FEMA regulated floodplain. While it is not
anticipated that there will be issues associated with FEMA permitting or documentation, WLS will
coordinate with the local floodplain administrator as needed and prepare the required documentation to
obtain approval for any FEMA regulated impacts. In addition, the project will be designed so that any
increase in flooding will be contained within the Bank boundary and will not impact adjacent landowners,
therefore hydrologic trespass will not be a concern.
3.4.5 Invasive Species
Within the proposed project boundary, there are several areas with a substantial community of the
invasive plant species Chinese Privet (Ligustrum sinense). A few additional pockets of additional invasive
species (multiflora rose) occur sporadically within the Bank area. WLS will develop a comprehensive
eradication, control, and monitoring program, using mechanical and chemical control techniques to
control invasive plant species currently on site and to prevent future proliferation.
3.4.6 Cultural Resources
In accordance with the National Historic Preservation Act, WLS investigated and confirmed that the
proposed project area and property does not contain nor is it adjacent to any properties listed in the
National Register with the State Historic Preservation Office. There are several sites located within
approximately one mile of the proposed project area, most of which are survey only and are not
registered. The closest such site was the Bailey House, located approximately 0.2 miles north east of the
project area. More recent aerial photography shows that this site has been demolished and removed.
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Upper Rocky Mitigation Bank Draft Prospectus
There are two sites on the National Register that are within the vicinity of the proposed project site. Potts
Plantation is a historical farm site located approximately one mile north. The South Prong West Branch of
the Rocky River flows through this property, but it is upstream of the confluence with the proposed project
and no impacts are expected to this registered property. The historical house Beaver Dam is located
approximately 1.1 miles north east of the proposed project area. No impacts to the property will occur
due to the Bank project.
3.4.7 Threatened and Endangered Species
According to the U.S. Fish and Wildlife Service, there are four species listed as endangered in Mecklenburg
County: Carolina heelsplitter (Lasmigona decorata), smooth coneflower (Echinacea laevigata),
Schweinitz's sunflower (Helianthus schweinitzii), and Michaux's sumac (Rhus michauxii). One species, the
Northern Long Eared Bat (Myotis septentrionalis) is listed as threatened.
The shade -intolerant Michaux's sumac typically occurs in open habitat that is frequently disturbed by
mowing or, historically, by fire. The smooth coneflower's habitat is dry limestone bluffs, bare rock/cliff,
and disturbed areas where the flower can receive full or partial sunlight. Schweinitz's sunflower also
prefers open areas, such as utility right-of-ways, with thin, clayey soils.
All of the endangered plant species have similar habitat requirements and there is some appropriate
habitat on the Bank. All areas of appropriate habitat were carefully inspected, within the pasturelands
and along the transition zones between open and forested regions. No individuals of these three species
were observed during the field investigation.
The Carolina heelsplitter is a relatively large, freshwater mussel endemic to several river drainages in
North and South Carolina. The species is reported to inhabit small to large streams and rivers. They are
usually found in muddy sand, muddy gravel, or mixed sand and gravel, near stable, well -shaded stream
banks. Historically, the range included the Catawba and Pee Dee river systems in North Carolina. Only
two small populations are known to exist in North Carolina and those are located in Union County. The
only appropriate habitat on the Site may have been Reach 1 that runs along the northeastern border. This
stream has been impacted by historic straightening of the channel with severely eroded, unstable banks.
It is highly unlikely that this stream would provide the stable habitat required by this species.
As part of due diligence and to avoid violation of the USFWS Norther Long-eared Bat Final 4(d) Ruling,
WLS contacted the USFWS to determine if any known hibernacula were located in Mecklenburg County.
None are known to exist there.
This area is not listed as critical habitat for any listed endangered or threatened species and the proposed
Bank should not negatively impact any listed species.
3.4.8 Conditions Affecting Hydrology
A series of beaver dams exist throughout Reaches 7 and 8. Relict beaver dams within Reach 7 are
contributing to the functional wetlands that have formed and will likely remain. Active beaver dams
within Reach 8 are causing water to pond and will be removed during restoration activities. The removal
of beavers is not expected to adversely affect the hydrology of the site.
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Upper Rocky Mitigation Bank Draft Prospectus
There is a culverted road crossing at the end of the project (Bailey Road crossing). This culvert will remain
in place. Therefore, design elevations will tie into this reference point.
There are several ditches throughout the Bank site. These ditches were historically used to drain wetlands
and create arable land for farming. These ditches will be plugged during restoration activities to prevent
them from negatively affecting hydrology on the completed project.
3.4.9 Adjacent Land Use
The Bank adjacent land use includes a high school, an established residential community, a developing
residential community, and agriculture and forestry. None of these land uses will have negative impacts
on the operation of the Bank.
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Upper Rocky Mitigation Bank Draft Prospectus
4 Proposed Bank Conditions
4.1 Objectives of proposed mitigation bank
The Bank will provide numerous water quality and ecological benefits within the Upper Rocky River
Watershed, which ultimately drains to the Yadkin River. The Bank is located in the West Branch Rocky
River - 03040105010010 Targeted Local Watershed (TLW), which is characterized by increasing
development pressures (NCEEP 2009). The placement of the proposed bank will provide significant long
term protection of natural resources and will meet the general restoration and protection goals outlined
in the 2009 Lower Yadkin Pee -Dee River Basin Restoration Priorities (RBRP) (NCEEP 2009) and in the draft
Rocky River Watershed Management Plan (MCSWS 2010). The Bank will meet these goals by:
• Reducing in -stream erosion and sediment/nutrient inputs by rebalancing imposed shear forces
and sediment transport capacity with sediment supply
• Reestablishing floodplain connectivity of the currently incised channel
• Prevent active headcuts from migrating farther upstream
• Restoring, preserving and protecting riparian, riverine wetlands
• Increasing habitat for benthic macroinvertebrates by incorporating habitat features such as
woody materials, pools and backwaters, riffles and structures.
The Bank reaches show the classic signs of habitat degradation associated with the transition of a
watershed from an agricultural community to an urban development through hydromodification, severe
channel incision, and a loss of wetland habitat. Our goal is to reestablish long-term stability by rebalancing
the watershed's geomorphic and hydrologic processes. Through the restoration of on-site streams and
associated wetlands, the design will recondition the site to create natural geomorphic processes leading
to enhanced habitat quality and greater riparian function. Complementing the restoration effort, the
design will also incorporate stormwater treatment to minimize the hydrologic effects of urbanization in
the watershed.
4.2 Conceptual Mitigation Plan
The Bank will involve the potential restoration, preservation and permanent protection of approximately
12,109 linear feet of existing streams. WLS's comprehensive design approach utilizes the entire suite of
stream mitigation practices, from Priority Level I Restoration to Preservation, and appropriately addresses
all of the intermittent and perennial stream reaches at the project site, including protecting or enhancing
riparian buffers along all of the project stream reaches, and limiting the number of stream crossings, thus
providing the maximum functional uplift and utilizing a true watershed approach.
The proposed Bank will provide adequate floodplain access to all stream reaches. For any Bank reach
along which Priority Level II Restoration must be utilized, the following elements will be incorporated into
the proposed design and construction:
• Floodplain bench excavation grading will extend a minimum of 1.5 bankfull widths beyond the
stream belt width such that meandering floodplains are not created.
• All proposed floodplains will be constructed such that they are over -excavated to accommodate
replacement of topsoil.
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Upper Rocky Mitigation Bank Draft Prospectus
• Design and construction oversight measures will ensure the proper harvesting, segregating,
stockpiling, storage, handling, overall management and replacement of A and B soil horizon
materials onto the excavated floodplain.
WLS has compiled and assessed watershed information including drainage areas, historic and current land
uses and development trends, geologic setting and landscape controls, soil types, and terrestrial plant
communities. WLS will compare the results of the existing conditions analyses along with reference data
from previous project implementation to determine the degrees of impairment and functional losses as
they relate to physical and biological processes, as well as aquatic resources. In order to develop an
appropriate design approach for the project reaches, the restoration potential must be determined to
maximize the highest functional uplift based on the hydrology, hydraulics, geomorphology,
physiochemical, and biological hierarchy. The design will utilize hybrid stream restoration approaches
that have been successfully implemented on past projects. This includes using process based analytical
tools when appropriate, as well as Rosgen's methodology, under which dimensionless ratios from
reference reach data (analog) and past project experience (empirical) are analyzed in order to develop
design criteria.
The proposed project will provide increased floodplain access throughout the project area for all
restoration reaches and will be monitored to demonstrate successful floodplain function. The
stream channel design will include analysis of the hydrology, hydraulics, shear stress, sediment
transport, and bankfull channel dimensions. WLS will consider three methods (field indicators if
present, published regional curve information, and hydraulic modeling) for estimating bankfull
discharge. The hydrology and hydraulics analysis will evaluate a range of significant flow discharges
and flood frequency curves to help determine an appropriate bankfull discharge. The bankfull
discharge will be used to select an appropriate channel geometry and help monitor long-term
performance.
Sediment transport calculations and stream power analyses will be performed for both the existing
degraded channels and the proposed design channels. WLS will assess the stream's transport competency
and capacity in order to quantify the stream's ability to move its sediment load. Small alluvial channels in
the Piedmont may have a relatively low sediment supply (i.e., first order streams) with fine grained
material, and therefore complex sediment transport calculations or models may not be necessary.
However, it is still critically important to perform watershed reconnaissance and estimate how much
sediment is being supplied to the project reaches by determining load rates from both within the channel
(bed/banks) and upland sources.
WLS will perform quantitative channel assessments that include pebble counts, collecting sediment
samples (pavement/sub-pavement, bar), and predicting streambank erosion rates using the BANCS
Method (BEHI/NBS) in order to evaluate bed and bank material characteristics and estimate sediment
yields. The bed material will be sieved and a grain size distribution developed. The results of the substrate
analyses will be used to classify the streams, and complete critical shear stress calculations required for
designing slopes/depths and predicting channel stability. Other observation methods, such as dendro-
geomorphic studies (bank root mass), bank pins/profiles, cross-section surveys, and time -series aerial
photography may also be used as a comparative analysis.
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Upper Rocky Mitigation Bank Draft Prospectus
Additionally, WLS will calculate stream power and compare the results to stable reference and published
values to reduce uncertainties. If the results fall outside common stable ranges for similar stream types
and slopes, multiple design iterations and methods, such as the Copeland Stability Curve, HEC -RAS -SAM
modeling program, will be run to confirm that sediment loads can be transported adequately through the
system without containing excess energy in the channel and verify that the design will not excessively
aggrade or degrade.
In -stream structures will be utilized for grade control, streambank protection, and improving bedform
diversity and habitat. All in -stream structures will be constructed from materials naturally found at the
project site such as hardwood trees, trunks/logs, brush/branches, gravel, stone, and small boulder
materials. Rock used for structures has been harvested on-site from the adjacent development. In order
to ensure sustainability of those structures, WLS will use methods of structure design and construction
that have proven successful on numerous past projects in the same geographic region. WLS may also
incorporate bioengineering practices, when appropriate, that use biodegradable materials and fabrics,
uncompacted soils, live plant cuttings, and native vegetation to stabilize streambanks. Bioengineering
treatments will provide initial bank stability that allows for the quick establishment of deep-rooted
vegetation along the eroding streambanks. Once established, these live, dormant plant cuttings will
provide long-term stability to the treated areas.
WLS has field verified that the project site has adequate, viable construction access, staging, and stockpile
areas. Note that physical constraints or barriers, such as stream crossings, account for less than three
percent of the proposed total project footage within the conservation easement area. These same
existing site access points and features will be used for future access after the completion of construction.
Where practicable, impacts to existing native riparian buffer vegetation will be minimized. The use of
native species riparian buffer transplants will be maximized as well. Any potential impacts to existing
wetland areas will be avoided during construction, with only temporary, minimal impacts expected only
as necessary for maximized permanent stream, wetland, and riparian buffer functional uplift.
4.3 Alternative Outcome without Bank
Without the proposed bank, it is expected that the watershed will continue to increase in impervious
areas and will undergo further urbanization and development. The Bjorneboe parcels will most likely be
logged and subdivided. The Mayes property is well suited for development, as well. The Beverly property
will potentially continue to degrade due to its current state of incision. Due to the current stream
conditions (incised and unhealthy), the existing and future watershed modifications will likely exacerbate
on-site stream and wetland degradation further impacting on-site and downstream water quality. The
placement of the Bank and restoration of on-site wetlands and streams is the likely only solution to
providing significant water quality benefits.
4.4 Reference Ecosystems
Reference ecosystems will be identified that represent similar conditions to the restored stream and
wetland system. Reference wetlands exist on-site where preservation is proposed. Reference streams
exist upstream of Reach 4. Additional reference reaches will be identified by the designer before design
begins.
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Upper Rocky Mitigation Bank Draft Prospectus
5 Bank Establishment and Operation
The URMB will be established as a single -site bank. The compensatory credits will be available to public,
private, and non-profit customers. The proposed bank will include a combination of stream restoration
and enhancement level I activities, depending upon the need of the individual reach and the highest
ecological lift possible.
The 8 -digit HUC is rapidly developing, so we anticipate a consistent need for both stream and wetland
credits. In addition, the City of Charlotte Umbrella Mitigation Bank is lacking wetland credits. Therefore,
any credits generated by URMB may be available to the City as well.
5.1 Proposed Credit Types
Expected credit types are Stream Mitigation Units (SMUs) and Wetland Mitigation Units (WMUs). Warm
stream credits will be generated through restoration and enhancement I activities (Table 4). Riparian,
riverine wetlands credits will be generated through restoration (both re-establishment and
rehabilitation), enhancement, and preservation activities (Table 5).
Table 4. Proposed Stream Mitiaation Units
1,846
Restoration (1:1)
1,846
711
Restoration (1:1)
711
1,369
Restoration (1:1)
1,369
614
Restoration (1:1)
614
3,110
Restoration (1:1)
3,110
258
Enhancement 1 (2:1)
129
246
Enhancement 1 (2:1)
123
723
Restoration (1:1)
723
160
Restoration (1:1)
160
132
Enhancement 1 (2:1)
66
1,176
Preservation (5:1)
235
835
Enhancement 1 (2:1)
417.5
800
Restoration (1:1)
800
129
Enhancement 1 (2:1)
64.5
10,368
Table S. Proposed Wetland Mitiaation Units
1.70
Enhancement (2:1)
0.85
3.10
Enhancement (2:1)
1.55
1.15
Preservation (5:1)
0.23
0.05
Preservation (5:1)
0.01
0.20
Rehabilitation (1.5:1)
0.13
0.30
Preservation (5:1)
0.06
9.60
Re-establishment (1:1)
9.60
12.43
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Upper Rocky Mitigation Bank Draft Prospectus
5.2 Credit Release Schedule
All credit releases, except the initial release, will be based on the total number of credits generated as
reported by the as -built survey. The initial credit release will be based on the total number of credits
estimated in the 60% design phase. The credit ledger will be managed by WLS and approved by the
District. The estimated credits will be released following District guidance, as shown in Table 6 below.
Table 6. Credit Release Schedule
Bank establishment
15% 15%
Completion of all initial physical and biological
improvements made pursuant to the Mitigation Plan
15% 30%
Year 1 monitoring report demonstrates that channels
are stable and interim performance standards have
10% 40%
been met
Year 2 monitoring report demonstrates that channels
are stable and interim performance standards have
10% 50%
been met
Year 3 monitoring report demonstrates that channels
are stable and interim performance standards have
15% 65%
been met
Year 4 monitoring report demonstrates that channels
are stable and interim performance standards have
5% 70%
been met
Year 5 monitoring report demonstrates that channels
are stable and interim performance standards have
15% 85%
been met
Year 6 monitoring report demonstrates that channels
are stable and interim performance standards have
5% 90%
been met
Year 7 monitoring report demonstrates that channels
are stable and interim performance standards have
10% 100%
been met
5.3 Service Area
The Bank will provide compensatory mitigation credits for permitted impacts to Waters of the United
States in the Yadkin River Watershed, HUC 03040105. The Bank is further characterized by the 14 -digit
HUC 03040105010010, which is managed under the Upper Rocky River and Clarke Creek Local Watershed
Plan (LWP). It is also located within a NC Targeted Local Watershed (TLW).
The Rocky River Watershed has experienced drastic increases in urbanization over the last 10-15 years.
Many stream systems have been straightened as a result of this growth, along with the extensive
agricultural practices that dominated the area previously. Like other developing watersheds, higher loads
of nutrients, metals, and sediment are more typically found here than in stable watersheds.
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Upper Rocky Mitigation Bank Draft Prospectus
A 2004 NCEEP planning initiative study identified much of the watershed as having potential for excessive
erosion, based on soil types, imperviousness and other factors (NCEEP 2004). The Rocky River and its
tributaries is listed as impaired on the 2014 303(d) list for ecological/biological integrity, mercury in fish
tissue, copper, turbidity, and zinc. The Rocky River is also governed by a TMDL for fecal coliform (EPA
2014).
MCSWS composed a draft Watershed Management Plan in 2010. The Watershed Management Plan
divided the watershed in 13 sub -basins to compare and locate priority areas. Using upland land use
characterization to compare the sub -basins, the proposed Bank basin ranks second in fecal coliform,
second in total nitrogen, second in total phosphorus, sixth in TSS, third in copper, second in
imperviousness, and sixth in buffer impacts (CMSWS 2010).
The report assessed 37 individual reaches within the watershed using BEHI, Near Bank Stress (NBS),
Simon's Channel Evolution Model, and Rapid Bioassessment Protocol Forms. The main tributaries of the
Upper Rocky River Mitigation Bank were three of the studied reaches. These reaches were recommended
for restoration and enhancement (1). The sub -basins were again compared using the results of these
studies. The Bank basin, upstream/headwaters of the South Prong, West Branch of the Rocky River, was
consistently rated in the worst condition, and as such, is listed as a Priority Basin. The Bank basin is a
priority due in part to the presence of significant institutional land use and high density residential
development; the basin was ranked as having the highest average erosion rate per reach, and the worst
basin -wide degradation (CMSWS 2010).
5.4 Proposed Financial Assurances
Financial assurances will be in the form of casualty insurance. WLS has begun the process of securing
coverage for the Bank. Details will be finalized prior to completion of the MBI.
5.5 Long -Term Management
The Bank will be protected in perpetuity by conservation easements that extend at least 50 feet from
stream centerlines and encompass all wetland areas.
The responsible party for long-term management has not yet been chosen, but will be secured prior to
publishing the MBI. Financial assurances for long-term management will be approved by the IRT prior to
the commencement of any Bank establishment activities.
Water & Land Solutions Page 27
Upper Rocky Mitigation Bank Draft Prospectus
6 Citations
Mecklenburg County Storm Water Services (MCSWS), 2010. "Rocky River Watershed Management
Plan." Draft version obtained from Mecklenburg County Storm Water Services direct contact.
Environmental Protection Agency (EPA), 2014. "Impaired Waters, TMDL Pollutant: Fecal Coliform, TMDL
ID: 4301." Accessed via:
https://iaspub.epa.gov/watersIO/attains_impaired_waters.control?p_tmdl_id=4301&p_tribe=&
p_pol luta nt_id=500&p_report_type=
North Carolina Ecosystem Enhancement Program (NCEEP), 2004. "Upper Rocky River/Clarke Creek Local
Watershed Plan." Accessed via:
http://www.nceep.net/services/lwps/Clarke_Creek/Introduction.html
NCEEP, 2009. "Lower Yadkin Pee -Dee River Basin Restoration Priorities 2009." Accessed via:
https://ncdenr.s3.amazonaws.com/s3fs-
public/Mitigation%20Services/PublicFolder/Work%20With/Watershed%20PIanners/Yadkin_Pee
_Dee_RBRP_2009_Final.pdf
N.0 Stream Functional Assessment Team. "N.C. Stream Assessment Method (NC SAM) User Manual,
Version 2.1," August 2015. Print
N.C. Wetland Functional Assessment Team. "N.C. Wetland Assessment Method (NC WAM) User Manual,
Version 4.1," October 2010. Print
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