HomeMy WebLinkAbout20160299 Ver 1_Mitigation Update PN with Document_FINAL public posted 10-24-2016_20170428I I
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US Army Corps
Of Engineers
Wilmington Dish-ict
PUBLIC NOTICE
Issue Date: October 24, 2016
POC: Todd Tugwell
US Army Corps of Engineers
Wilmiilgton District
3331 Heritage Trade Drive, Suite 105
Raleigh, NC 27587
Einail: todd.tu_w� ell(c�usace.army.mi]
FEDERAL PUBLIC NOTICE
NOTIFICATION OF ISSUANCE OF GUIDACE FOR COMPENSATORY STREAM
AND WETLAND MITIGATION CONDUCTED FOR WILMINGTON DISTRICT
The Wilmington District is releasing updated compensatory mitigation guidance, entitled
Wilmington District Stream and Wetland Compensatory Mitigation Update. This
guidance document has been developed in coordination with the North Carolina
Interagency Review Team (NCIRT) to provide updates to existing District guidance for
compensatory mitigation. The NCIRT is a joint interagency team chaired by the USACE,
which includes representation from the US Fish and Wildlife Service, US Environmental
Protection Agency, National Marine Fisheries Service, NC Division of Water Resources,
NC Wildlife Resources Commission, NC Division of Coastal Management, and the NC
State Historic preservation Office. This guidance is applicable to stream and wetland
mitigation projects that are used to satisfy the requirements of Department of the Army
permits issued in accordance with Section 404 of the Clean Water Act and Sections 9
and 10 of the Rivers and Harbors Act of 1899. In particular, these updates are intended
to bring District monitoring requirements up to the standards established in 33 CFR part
332 — Compensatory Mitigation for Losses of Aquatic Resources (Mitigation Rule),
issued in April, 2008, and Regulatory Guidance Letter 08-03, issued in October, 2008,
which establishes minimum monitoring requirements for compensatory mitigation
projects.
This guidance document is effective as of the date of this public notice and should be put
to immediate use for new compensatory mitigation projects. Further details pertaining to
which mitigation projects this guidance applies to can be found in Section II of the
document. This guidance was previously put out for public comment on February 22,
2013. Comments and new information received since the issuance of the first public
notice have been incorporated into the current version. The Corps will be continually
accepting comments related to this guidance from the public, Federal, state, and local
agencies and officials; Indian Tribes; and other interested parties. This document is
intended to be updated regularly as new techniques and information becomes available.
The most recent copy of this document will be available for review and download on the
Version 7.8.2014 Page 1
Wilmington District Regulatory In-lieu Fee and Bank Information Tracking System
(RIBITS) webpage at https://ribits.usace.army.mil.
Comments can be submitted to Mr. Todd Tugwell, Wilmington District, US Army Corps
of Engineers, 3331 Heritage Trade Drive, Suite 105, Raleigh, NC 27587. If you have
questions about this proposal, please contact Mr. Tugwell at (919) 554-4884 x58.
Version 7.8.2014 Page 2
Wilmington District Stream and Wetland Compensatory Mitigation Update
Section
I.
II.
III.
IV.
V.
VI.
VII.
VIII.
IX.
X.
XI.
XII.
XIII.
XIV.
Purpose
North Carolina Interagency Review Team — October 24, 2016
Contents
Purpose
Applicability
Relationship to Other District Guidance Documents
General Monitoring Requirements
Planted Vegetation Monitoring
Stream Channel Stability and Stream Hydrology Monitoring
Stream Water Quality, Macroinvertebrate, and Fish Monitoring
Headwater Stream Monitoring
Wetland Hydrology Monitoring
Visual Monitoring
Stream Buffers
Remedial Actions
Monitoring Schedule
Credit Release Schedules
Page
1
2
3
4
5
7
10
12
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The U.S. Army Corps of Engineers (USACE), Wilmington District, has prepared this guidance
document in coordination with the North Carolina Interagency Review Team (NCIRT) to provide
updates to existing District guidance for compensatory mitigation. The NCIRT is a joint interagency
team chaired by the USACE, which includes representation from the US Fish and Wildlife Service,
US Environmental Protection Agency, National Marine Fisheries Service, NC Division of Water
Resources (NCDWR), NC Wildlife Resources Commission, NC Division of Coastal Management, and
the NC State Historic Preservation Office. This guidance is applicable to stream and wetland
mitigation projects that are used to satisfy the requirements of Department of the Army (DA)
permits issued in accordance with Section 404 of the Clean Water Act (CWA) and Sections 9 and 10
of the Rivers and Harbors Act of 1899. In particular, these updates are intended to bring District
monitoring requirements up to the standards established in 33 CFR part 332 — Compensatory
Mitigation for Losses of Aquatic Resources (Mitigation Rule), issued in April, 2008, and Regulatory
Guidance Letter (RGL) 08-03, issued in October, 2008, which establishes minimum monitoring
requirements for compensatory mitigation projects.
Compensatory mitigation is intended to replace functions of stream and wetland systems lost
through Department of the Army (DA) permit actions. The goal of mitigation projects is to take
degraded stream and wetland systems and return them to a stable condition, but fully replacing
lost functions may take much more time, perhaps decades. Because of this, monitoring is required
to demonstrate that a site is trending towards success and is on target to meet the goals and
objectives outlined in the Mitigation Plan. It is critical that all Mitigation Plans are developed with
appropriate and attainable goals and objectives. The fundamental purpose of a monitoring program
is to provide reliable data upon which valid conclusions can be reached regarding the success or
failure of a mitigation site and to demonstrate whether the goals and objectives of the Mitigation
Plan are being met. Success is documented through the use of performance standards, which are
defined in the Mitigation Rule as "observable or measurable physical (including hydrological),
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chemical, and/or biological attributes that are used to determine if a compensatory mitigation
project meets its objectives". Other aspects of monitoring that aren't captured in the performance
standards, such as visual observations, can also help demonstrate that desired site conditions are
being attained. Another goal of having consistent performance standards is the ability to compare
data across the state of North Carolina and evaluate whether current practices are working or if
changes are needed.
In order to assist with determining the initial baseline for all mitigation sites, a jurisdictional
determination must be conducted to establish the preexisting extent of streams, wetlands, or other
jurisdictional features on the site. This should be done shortly after the initial review of the
mitigation site by the USACE and NCIRT. The determination will be approved by the USACE county
Project Manager. Additionally, mitigation proposals (prospectuses for new banks and proposals to
add umbrella bank or ILF sites) should always include results from the NC Stream Assessment
Method (NC SAM) and NC Wetland Assessment Method (NC WAM) for all streams and wetlands
proposed for credit. These rapid assessment methods have been adopted by the District, and are
valuable as a mitigation site screening tool and for establishing the baseline functional condition of
proposed sites (e.g., preservation sites should generally have results that indicate a current high
functional condition, while enhancement and restoration sites should have results that indicate an
impaired functional condition). These tools may also help demonstrate the specific areas where
functional improvements may be made. Results from these assessment methods will not be used
in determining mitigation success. The use of NC SAM and NC WAM do not replace the need to
conduct more thorough assessments and measurements of existing conditions on proposed stream
and wetland mitigation sites.
II. Applicability
This update is intended to compile several District documents and draft procedures into one
document, and also to provide a predictable and consistent approach to monitoring mitigation sites
The District intends this guidance to be a living document, which will be routinely updated with new
information and methods. The most recent version of this document will be available on the
Wilmington District Regulatory In-lieu Fee and Bank Information Tracking System (RIBITS) website,
at https://ribits.usace.armv.mil. This guidance applies to all sources of stream and wetland
compensatory mitigation, including permittee-responsible mitigation (PRM) sites, mitigation banks
(public, private, and single-client), and In-Lieu Fee (ILF) projects, which includes all projects
implemented by the North Carolina Division of Mitigation Services (NCDMS). While this document
establishes the basic expectations for developing and monitoring compensatory mitigation sites, we
acknowledge that there are sites where unique circumstances may call for alternative monitoring
approaches. Accordingly, any provision within this guidance may be modified on a case-by-case
basis for a specific project if the conditions or circumstances justify such a change. All modifications
to the provisions contained in this document must be approved in advance by the USACE in
consultation with the NCIRT. Where modifications are approved, the Mitigation Plan should
explicitly identify those changes and provide a detailed explanation for the proposed changes.
As stated earlier, the intent of monitoring is to demonstrate that a site is trending towards meeting
the overall goals and objectives of the Mitigation Plan. Failure to meet any particular performance
standard will not necessarily result in a determination that the goals and objectives of the Mitigation
Plan have not been met. The final decision regarding the applicability of any provision contained in
this guidance document, including the success of specific performance standards, the suitability of
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a site to be used as compensatory mitigation for authorized impacts, or the amount of credit
generated by a specific site shall be made by the District Engineer in consultation with the NCIRT.
For PRM, the roles and responsibilities ofthe NCIRT referenced in this document are carried out by
the USACE Project Manager (PM), through coordination with the other resource agencies in the
NCI RT.
For DA permits with impacts that are compensated through PRM, the mitigation sites are typically
much smaller than the typical bank or in-lieu fee site. The Mitigation Rule states that "the
submission of monitoring reports to assess the development and condition of the compensatory
mitigation project is required, but the content and level of detail for those monitoring reports must
be commensurate with the scale and scope of the compensatory mitigation project, as well as the
compensatory mitigation project type". Because of this, the requirements established in this
document may be reduced on a case-by-case basis by the PM to account for the reduced scope of
the mitigation. For example, mitigation associated with projects that are within the nationwide
permit thresholds (% acre and/or 300 linear feet of stream channel) may have reduced mitigation
requirements if it is determined to be appropriate by the District PM.
This guidance is applicable to both stream and wetland mitigation. Individual sections within this
document specifically identify what type of mitigation they apply to (i.e., preservation, restoration,
enhancement, and Creation) and whether they apply to stream sites and/or wetland sites. The
requirements of this document do not apply to mitigation sites that were initiated prior to the date
of this guidance, regardless of whether they are umbrella bank sites, ILF mitigation sites, or PRM
sites. This document applies to all modifications of existing bank and ILF instruments that are
initiated after the date of this guidance where additional sites are added to the instrument as part
of the modification. The term "initiated" is defined as the date when the District is in receipt of a
complete prospectus for new mitigation bank, a complete proposal to modify an existing mitigation
bank, or a complete DA permit application that includes a proposal for PRM. For NCDMS, the term
"instituted" is the same as the date a project is "instituted", as defined in the NCDMS Instrument,
approved on July 28, 2010, and also includes any projects submitted for any Requests for Proposals
advertised after the date of these guidelines.
Piedmont, Coastal Plain and Mountain Counties — Any reference to mountain counties in this
document applies to the following twenty-five North Carolina counties: Alleghany, Ashe, Avery,
Buncombe, Burke, Caldwell, Cherokee, Clay, Graham, Haywood, Henderson, Jackson, Macon,
Madison, McDowell, Mitchell, Polk, Rutherford, Stokes, Surry, Swain, Transylvania, Watauga, Wilkes
and Yancey. All other seventy-five North Carolina counties are considered either piedmont or
coastal plain counties.
III. Relationship to Other District Guidance Documents
These guidelines have been prepared in accordance with the Mitigation Rule. The requirements
provided in this guidance document are intended to replace the monitoring requirements found in
existing District mitigation guidance, including Section 11 of the 2003 Stream Mitigation Guidelines
(SMGs). Where conflicts exist between the requirements of this document and previous District
guidance, the requirements of this document will supersede those of other documents (not to
include Federal regulations or RGLs).
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IV. General Monitoring Requirements
This section deals with general monitoring requirements for all compensatory mitigation sites, with
the exception of preservation sites and non-forested coastal marsh wetland sites. As a rule, all
monitoring of mitigation sites must adhere to the minimum standards provided in RGL 08-03, which
is available on the Wilmington District RIBITS website.
A. Site monitoring for all stream and wetland compensatory mitigation projects must occur for
seven years post-construction, unless the District, in consultation with the IRT, agrees that
monitoring may be terminated early. If performance standards have not been met by year
seven, or if remedial actions are required, additional monitoring may be required to ensure
that a site is stable and that the target community is established on the site, otherwise the
project, or portions of the project, may be deemed to have failed.
B. Unless otherwise specified in the Mitigation Plan or banking instrument, monitoring reports
must be completed for all seven years and provided to the Corps of Engineers for review no
later than April 1 of the year following the monitoring. Failure to provide monitoring reports
by this deadline may result in additional monitoring, withholding the release of credits, and/or
suspension of credit sales. If the monitoring reports indicate that replanting is necessary,
additional monitoring may be required depending on the extent of replanting, the timing of
the replanting, and the type of stock used. Supplemental plantings that cover more than 20%
of a site, use small stock, or are conducted toward the end of the 7-year monitoring period
are more likely to require additional monitoring. Bank or structure repair, invasive control,
beaver management, conservation easement encroachments, or other remedial actions may
also require additional monitoring, depending on the extent of the problem.
C. Monitoring reports should be prepared in accordance with RGL 08-03, which identifies
specific contents and formatting of the report. Monitoring reports should include the data
collected for all applicable sections of this guidance; however, not all monitoring reports will
include the same information (e.g., monitoring reports submitted in years four and six will not
typically include vegetation plot data). Monitoring reports should include an executive
summary that state the overall monitoring results, to include stream and wetland hydrologic
monitoring, vegetation monitoring, water quality, fish and macroinvertebrate monitoring (if
applicable), and areas of concern (such as beaver activity, exotic/invasive vegetation, stream
instability, supplemental planting, etc.). Performance standards, as provided in the Mitigation
Plan or in the permit conditions, must be restated verbatim in the monitoring report. Where
graphs or tabular data are provided, they should be overlaid with as-built data and data from
preceding monitoring years (e.g., hydrology gauge data, stream cross-sections, etc.).
D. A final as-built survey must be submitted following the completion of all physical and
biological improvements, including planting, for every mitigation project to document
baseline conditions. As-built surveys should include photo documentation at all cross-
sections and monitoring instruments (hydrology gauges, crest gauges, etc.), a plan view
diagram, a copy of the recorded easement, verification of the installation of conservation
easement boundary markers, a longitudinal profile, and vegetation information (type and
number of species planted, and, if applicable, planting zones for targeted communities).
Stream lengths (and associated credits) should be calculated using the stream centerline, not
the thalweg, as this can be more easily verified in the project plans. As-built surveys should
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also indicate the locations of all monitoring activities (permanent vegetation plots,
groundwater and surface water gauges, crest gauges, cross-sections, bank pins, photo points,
water quality and aquatic biota sampling points, etc.). Any change to the projected wetland
acreage or stream linear footage and associated credit amounts stated in the mitigation plan
must be documented and explained in the as-built report. As-built reports must be provided
to the USACE within 90 days of completion of physical and biological improvements. As-built
surveys are not required for preservation-only projects.
V. Planted Vegetation Monitoring
The following requirements apply to all stream and wetland mitigation projects that include planting
of woody vegetation. Alternative vegetation planting and monitoring plans may be approved by
the NCIRT or PM on a case-by-case basis as necessary to accommodate non-standard techniques.
A. Vegetation Planting and Monitoring Requirements
1. Vegetation plots must be monitored for 7 years, with monitoring events occurring on
years 1, 2, 3, 5, and 7. If the Sponsor/Permittee chooses to conduct supplemental
monitoring, results may be considered toward meeting performance standards.
2. Vegetation planting/replanting should be conducted between November 15 and March
15, unless otherwise noted in the approved Mitigation Plan or remedial action plan.
3. Vegetation monitoring should be conducted between July 15t and leaf drop. It is
strongly recommended to monitor later in the growing season to capture any effects of
climatic or other conditions that may adversely affect vegetation survival. Failure to
identify these effects may result in additional monitoring.
4. Vegetation must be planted and plots established at least 180 days priorto the initiation
of the first year of monitoring (Year 1).
5. A combination of permanent fixed plots and random plots should be used to
demonstrate vegetation coverage. Random plots should not make up more than 50%
of the total required plots. Random plots may be a different plot type (e.g., circular,
transect, etc.), but should be the same size as the fixed plots. Additionally, the location
(GPS coordinates and orientation) of random plots for every year of monitoring must
be identified in the monitoring report, and the plots must be marked so the plots may
be evaluated in the field.
Permanent plots to sample vegetation should be randomly located in each of the target
communities. Plot sizes for the determination of stem density and vigor (height) should
be a minimum of 0.02 acre in size, and should typically be square or rectangular. For
projects that include stream channels, fixed plots should not overlap the stream (top-
of-bank to top-of-bank) to ensure that vegetation data does not include stream bank
live stakes.
Vegetation monitoring plots should be located across the site to provide a random
sampling of all the vegetation community types reestablished on the site. For projects
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that include both streams and wetland, the plots should be located to cover both the
stream buffers and wetlands if possible. The monitoring plots must make up a
minimum of 2% ofthe planted portion ofthe site with a minimum of4 plots. Exceptions
to this requirement may be provided on a case-by-case basis for very small sites or for
large, uniform sites. All exceptions to this requirement shall be specifically noted in the
approved Mitigation Plan.
8. Upon initial establishment of fixed vegetation plots (as-built baseline/year 0), the plot
corners must be identified in the field with markers. The plot should be divided into a
grid pattern so that each planted stem can be identified for future monitoring according
to its grid location within the plot.
9. Plot vegetation data collected must include:
• Within each fixed plot: species, height, grid location, planted versus volunteer,
and age (based on the year the stem was planted, or first observed for volunteers)
• Within each random plot: species and height
• For both fixed and random plots, all woody stems, including exotic and invasive
species, should be counted (exotic/invasive species will not count toward success
of performance standards)
10. Individual plot data for planted and volunteer species must be provided separately. Plot
data cannot be averaged across plots over the entire site to obtain a single figure for
stem density for the purposes of demonstrating success in meeting performance
standards. Averages will be considered by the NCIRT, on a case-by-case basis.
11. Supplemental plantings and volunteer plants must be present for at least two growing
seasons before counting toward meeting performance standards for monitoring year
five and seven.
12. Monitoring events should be used to evaluate the site for the presence of invasive
species, which should be noted in the monitoring report. (Implementation of invasive
species control measures should be conducted in accordance with the Adaptive
Management Plan, and may be required on a case-by-case basis as determined by the
NCIRT.)
13. Planting in rows to facilitate mowing between planted species is acceptable. Mowing
may be conducted once annually by the mitigation sponsor between monitoring years
one and five to reduce the competition by nuisance volunteer species or to treat
exotic/invasive plants, but no mowing activities can be conducted between March 15t
and June 30th. (Note that mowed volunteer trees should not be counted in plot data
presented in the monitoring report.)
14. Application of fertilizers may be conducted once at the time of planting only, unless
approved on a case-by-case basis as part of a remedial action plan. Herbicides may be
used to control nuisance volunteer, exotic and invasive vegetation, but they must be
applied in accordance with product labeling by a licensed applicator and any herbicides
used near streams must be approved for aquatic use. Aerial application of herbicides
must not be conducted.
B. Planted Vegetation Performance Standards
1. Within planted portions of the site, a minimum of 320 stems per acre must be present
at year three; a minimum of 260 stems per acre must be present at year five; and a
minimum of 210 stems per acre must be present at year seven.
2. For projects located in the coastal plain and piedmont counties, trees in each plot must
average 7 feet in height at year five and 10 feet in height at year seven. For projects
located in the mountain counties, trees in each plot must average 6 feet in height at
year five and 8 feet in height at year seven. Alternative performance standards for
vegetation vigor or density may be proposed in the Mitigation Plan for sites proposed
to be revegetated with slow growing species, woody shrub species, or primarily with
understory species (e.g., shrubs in currently forested areas, bogs, pine savannahs,
wetland mosaics with open spring ponds, etc.).
3. For any tree stem to count toward success for standard 1 or 2, it may be either planted
or volunteer, but it must be a species from the approved planting list included in the
Mitigation Plan. Other species not included on the planting list may be considered by
the IRT on a case-by-case basis. Additionally, any single species can only account for up
to 50% of the required number of stems within any vegetation plot. (Stems in excess
of 50% should still be shown on the monitoring table, but cannot be used to
demonstrate success.) In cases where plots are dominated by volunteer species,
remedial action as specified in the Adaptive Management Plan or as directed by the
NCIRT may be required. Exceptions to this requirement may be provided on a case-by-
case basis for sites with conditions that limit the planting list. All exceptions to this
requirement must be specifically noted in the approved Mitigation Plan.
VI. Stream Channel Stability and Stream Hydrology Monitoring
The purpose of the monitoring requirements and performance standards included in this section is
to demonstrate that the proposed in-stream work has effectively corrected channel bed and bank
instability when it is identified as a primary objective in the Mitigation Plan. Accordingly, the
requirements in this section apply to all stream mitigation reaches that utilize a restoration or
enhancement level I approach, and also to all enhancement level II reaches where in-stream work
is conducted that alters the channel dimensions below the bankfull elevation (e.g., laying back the
stream banks below bankfull elevation or raising/lowering the bed elevation). For the purposes of
this guidance document, a"reach" is defined as a continuous section of an individual tributary
where a similar design approach is applied (e.g., priority 1 restoration, priority 2 restoration,
enhancement level I, enhancement level II, or preservation). A reach is limited to a single tributary.
These performance standards do not apply to wetland mitigation or channels constructed in
accordance with the Headwater Stream Guidance (Section VIII).
A. Stream Channel Stability and Stream Hydrology Monitoring Requirements
1. Channel stability must be monitored for 7 years, with monitoring events occurring on
years 1, 2, 3, 5, and 7. If the Sponsor/Permittee chooses to conduct supplemental
monitoring, results may be considered towards meeting performance standards. It is
recommended that stream surveys for both project construction and project
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monitoring generally follow the methodology contained in the USDA Forest Service
Manual, Stream Channel Reference Sites (Harrelson, et.al, 1994 - available on the
Wilmington District RIBITS website at http://ribits.usace.army.mil).
2. A longitudinal profile of the thalweg, water surface, bankfull, and top of bank, must be
collected during the as-built survey of the constructed channel to compare with future
geomorphological data. Additional longitudinal profiles are not required during routine
channel stability monitoring (years 1 through 7) unless the monitoring efforts
demonstrate channel bank or bed instability, in which case additional longitudinal
profiles may be required by the NCIRT along channel reaches of concern to track
changes in the channel and demonstrate stability.
3. Permanent, monumented cross-sections must be installed at an approximate frequency
of one per 20 bankfull-widths, measured along the centerline of the channel. In general,
the locations should be selected to represent approximately 50% pools and 50% riffle
areas. Flexibility in the location and frequency is allowed for cross-sections and should
be based on best professional judgment. The selection of locations should always
include areas that may be predisposed to potential problems, such as particularly tight
meanders, meanders just downstream from channel confluence points, or areas where
in-channel work corrected existing bank failures. In the case of very narrow streams,
two cross-sections per 1,000 linear feet will generally be sufficient. All channel cross-
sections within riffles must include measurements of Bank Height Ratio (BHR) and
Entrenchment Ratio (ER), which must be documented in monitoring reports.
4. When stream reaches show accelerated instability the NCIRT will generally require
some form of ineasured documentation to assess stability over time. Two acceptable
methods include the installation of a bank pin arrays or the addition of cross sections.
This will generally be required whenever annual monitoring demonstrates an increase
of greater than 15% in cross-sectional area, or when visual monitoring indicates
potential bank instability. Bank pins are not required where the size of the channel
makes it impractical to use them (e.g., channels that are too narrow to allow
installation) — these areas should be monitored through photo points instead. Bank
pins may consist of chain, rebar, or wire driven horizontally into the bank face, and
should be a minimum of 3 feet long. A minimum of one pin per 2 feet of bank height
should be installed at each location, with the lowest pin installed just above the normal
water line and additional pins installed vertically above the first pins to the top of the
bank. Vertical series of pins should be installed in at least three locations along the
bank, centered on the area of potential instability. For instance, where erosion is
located within a stream meander, the pins should be installed at middle of the meander
bend, the upstream third of the meander bend, and downstream third of the meander
bend. The pins should be installed perpendicular and flush to the face of the stream
bank if rebar is used, and the length of exposed pin should be measured and reported
during each cross-section monitoring event. Once the exposure has been measured,
rebar pins should be hammered flush with the bank face. Lateral movement of the
stream banks as indicated by pin exposure must be reported in all monitoring reports.
5. Crest gauges must be installed to document the occurrence of bankfull events. A
minimum of one gauge must be installed on each tributary that is greater than 1000
E3
feet in length, with one gauge required for every 5000 feet of length on each tributary,
and a maximum of 5 gauges per tributary. For all Priority 1 projects and any project
that is designed to reconnect the stream to its floodplain, gauges should also be capable
of tracking the frequency and duration of overbank events (e.g., pressure transducer
gauges or other gauges that continually monitor events). Automated photo loggers
may also be used to document channel hydrology in lieu of crest gauges.
Where restoration or enhancement activities are proposed for intermittent streams,
monitoring gauges should be installed to track the frequency and duration of stream
flow events.
B. Stream Channel Stability and Stream Hydrology Performance Standards
1. All stream channels must receive sufficient flow throughout the monitoring period to
maintain an Ordinary High Water Mark (OHWM) in accordance with the requirements
of RGL 05-05, dated December 7, 2005, which establishes the extent of USACE
jurisdiction for non-tidal waters for CWA Section 404. Channels that are determined to
be non-jurisdictional will not be eligible to receive credit.
2. Continuous surface water flow within the tributaries must be documented to occur
every year for at least 30 consecutive days during the prescribed monitoring period.
This 30-day period can occur at any point during the year. Additional monitoring may
be required if surface water flow cannot be documented due to abnormally dry
conditions.
3. BHR must not exceed 1.2 at any measured riffle cross-section. This standard only applies
to reaches of the channel where BHR is adjusted to reference condition through design
and construction. Exceptions to this requirement may be approved on a case-by-case
basis, but all exceptions must be included in the final approved Mitigation Plan.
4. ER must be no less than 1.4 at any measured riffle cross-section. This standard only
applies to reaches of the channel where ER is altered to reference condition through
design and construction. Exceptions to this requirement may be approved on a case-
by-case basis, but all exceptions must be included in the final approved Mitigation Plan.
5. BHR and ER at any measured riffle cross-section should not change by more than 10%
from the baseline condition during any given monitoring interval (e.g., no more than
10% between years 1 and 2, 2 and 3, 3 and 5, or 5 and 7).
6. When bank pin arrays are required, average bank pin measurements at each cross
section (i.e., length of pin exposed due to lateral movement of the bank) cannot exceed
10% of as-built bankfull width during any given monitoring interval (e.g., no more than
10% between years 1 and 2, 2 and 3, 3 and 5, or 5 and 7), and individual bank pin
measurements must not exceed 20% of as-built bankfull width over the duration of
monitoring. When cross sections are added to document bank movement in certain
areas, bankfull cross sectional area must not increase by more than 15% over the
duration of monitoring.
E]
7. The stream project shall remain stable and all other performance standards shall be
met through four (4) separate bankfull events, occurring in separate years, during the
monitoring years 1 through 7.
VII. Stream Water Quality, Macroinvertebrate, and Fish Monitoring
The objective of the monitoring protocols included in this section is to directly measure physical,
chemical and biological metrics within restored and enhanced reaches of stream channels with the
intent of linking stream mitigation and functional uplift. Water quality, macroinvertebrate, and fish
community monitoring included in this section is not required, but is encouraged. For those projects
where this monitoring is conducted, additional credit of up to 2% may be generated for each
tributary to be monitored in accordance with the protocols specified below. (The additional credit
will be calculated based on the credit generated by the tributary before applying any additional
credit resulting from wider buffers, BMPs or other measures.) At a minimum, water quality and
macroinvertebrate sampling must be conducted to receive the additional credit. If fish sampling is
also conducted, the additional credit ratio may be adjusted upward to account for the added
sampling. Generally, this monitoring should be conducted on reaches where a restoration or
enhancement approach is used. In some cases, monitoring of preservation reaches for additional
credit may also be approved (e.g., where it is anticipated that habitat uplift may occur due to
upstream enhancements or where on-site preservation is used as a reference). Additional credits
generated by this monitoring will be added to the total credit amount for the project and released
according to the standard release schedule. All proposals to monitor water quality,
macroinvertebrates and fish must be reviewed and approved by the USACE in consultation with the
NCIRT.
These water quality and macroinvertebrate indicators are inherently sensitive to changes that occur
anywhere within the watershed draining to the mitigation project, such as land use changes,
meteorological changes (droughts, storms, etc.), or pollution entering the watershed (e.g., herbicide
use, fertilizer application, road runoff, etc.). Improvements may also occur slowly since they
develop in response to other modifications, such as buffer replanting or in-stream habitat
improvements. For macroinvertebrates, there may also be a lag period for re-colonization by the
desired species. For these reasons, Mitigation Plans that propose water quality and
macroinvertebrate monitoring should always include a narrative that describes the proposed
monitoring activities and those land uses within the watershed(s) draining to the project that may
affect water quality or macroinvertebrate communities. It is possible that results may not always
demonstrate a measurable improvement over pre-construction conditions through the seven-year
monitoring timeframe, and consequently, project success will not be tied to these metrics.
Performance standards associated with water quality, macroinvertebrate and fish data have not
been developed at this time. These monitoring protocols have been added in part to provide the
NCIRT with data that may be used to support future guidance, including making these protocols
mandatory or tying functional uplift to credit production.
A. Water Quality Monitoring Protocol
1. Water quality sampling should be conducted prior to construction and during the
monitoring period using a continuous recording sampling device. (Alternative
monitoring protocols using single event sampling instead of continuous recorders may
10
be approved on case-by-case basis; however, credit adjustments may be different
depending the on the monitoring protocol proposed.)
2. Water quality sampling should at a minimum include measurements of acidity (pH),
temperature, dissolved oxygen, and conductivity. Additional sampling of other water
quality parameters may be proposed on a project-by-project basis, particularly if they
support specific goals identified in the Mitigation Plan, such as a reduction in fecal
coliform or nutrient levels.
3. At a minimum, each project tributary longer than 1000 feet should be sampled at two
locations, though shorter tributary reaches may also be monitored (and allotted
additional credit). Sampling points should be located as close as possible to the upper
and lower end of the tributary in order to detect any change. If possible, the upstream
sampling points should be located just upstream from the start of restoration or
enhancement activities. Sampling points should be located where water is freely
flowing and with sufficient depth to allow sampling to be conducted without
disturbance to streambed sediments.
4. Water quality sampling equipment and reference solutions must be maintained and
calibrated in accordance with manufacturer specifications. Personnel installing and
conducting the monitoring must be adequately trained.
5. Results should be presented annually in the monitoring report, and include a summary
of the current results and all past monitoring events in tabular format.
B. Macroinvertebrate Monitoring Requirements
1. Macroinvertebrate sampling should be conducted prior to construction and once a year
during monitoring years 3, 5, and 7.
2. A sampling point should be conducted on every perennial tributary greater than 1000
feet in length. Additional sampling points are required per additional 2000 feet of
length on each tributary (1000' = 1 point, 3000' = 2 points, 5000' = 3 points, etc.).
Sampling points should be located on riffles, with the first sampling point located on
the most downstream riffle on the tributary. The appropriate sampling location should
be based on riffle condition and best professional judgment. Pre-construction sampling
points may be located in different locations than during the monitoring period sampling
to ensure that appropriate habitat is included in the sample (e.g., riffles, leaf packs,
undercut banks, woody debris, etc.); however, sampling conducted during the
monitoring period should occur within the same riffle year-to-year, if possible.
3. A reference location should also be sampled for comparison purposes. The reference
point should be located on a relatively stable reach in an undisturbed setting, located
as close to the mitigation site as possible, and within the same watershed. The
reference sampling point should be on a stream with similar watershed characteristics
(drainage size, ecoregion, imperviousness, etc.). The reference location may be located
within an on-site preservation reach, or upstream of the mitigation site if stream
11
conditions are appropriate, but should not be located downstream of mitigation
activities, regardless of whether it is on-site.
4. The sampling should be conducted in accordance with the NCDWR Qual 4
macroinvertebrate sampling protocol, which is described in the most current version of
the Standard Operating Procedures for Collection and Analysis of eenthic
Macroinvertebrates, February 2016 (Version 5.0). If the stream is large (greater than a
3 square mile watershed), a mix of Qual 4 and the Standard Qualitative (Full Scale)
methods may be appropriate. Samples should be collected by someone trained in and
experienced with the method. In general, sampling should be conducted during the
same time of year to minimize seasonal differences in the data from year-to-year.
Additionally, sampling should be conducted at the same time as water quality
monitoring, and within the index period referenced in the North Carolina Division of
Water Resources (NCDWR) document entitled Small Streams Biocriteria Development,
dated May 29, 2009. Both documents referenced above are available on the NCDWR
Biological Assessment Unit homepage (https://deq.nc.�ov/about/divisions/water-
resources/water-resources-data/water-sciences-home-pa�e/biolo�ica I-assessment-
branch) under the Benthos Links section. The number of samples collected should be
based on the size and complexity of the site. Macroinvertebrate samples should be
identified to the lowest practical taxonomic level (usually Genus) by a qualified
taxonomist (this qualification can be demonstrated by being a NCDWR certified
laboratory for macroinvertebrates).
5. Results should be presented in the current monitoring report and include, at a
minimum, a list of taxa collected at each site for each sampling event, as well as an
enumeration of the Ephemeroptera, Plecoptera, and Trichoptera (EPT) taxa and a Biotic
Index (see the NCDWR Standard Operating Procedures for Collection and Analysis of
Benthic Macroinvertebrates). Each report should include a summary of the current
results and all past monitoring events in tabular format. Other summary or comparison
statistics may also be acceptable on a case-by-case basis.
C. Fish Sampling
1. Fish sampling may also be conducted where the project goals include the restoration or
enhancement of fish habitat. In general, fish sampling should be conducted prior to
construction and once a year during monitoring years 3, 5, and 7; however, the specific
protocol for fish sampling will likely vary depending on the site and species sampled,
and must be included in the mitigation plan for approval by the USACE in consultation
with the NCIRT.
VIII. Headwater Stream Monitoring
This section is applicable to projects developed in accordance with the document entitled
Information Regarding Stream Restoration With Emphasis on the Coastal Plain, Version 2, dated
April 4, 2007, referred to here as the Headwater Stream Guidance (available on the Wilmington
District RIBITS website). The Headwater Stream Guidance allows for restoration of streams that do
not typically require construction of pattern, dimension, and/or profile. Restoration of the streams
in these systems should be achieved through the reestablishment of appropriate hydrology and
12
hydraulics, which leads to the passive development of headwaters stream geomorphology over
time. Site construction may include some less invasive construction measures such as ditch filling,
field crown removal, planting bed/crop row leveling, and the return of hydrology to historic braids
or channels (if still present). The requirements in this section apply to all stream mitigation reaches
that utilize the Headwaters Stream Guidance. The protocols for constructed channels included in
Section VI (Stream Channel Stability and Stream Hydrology Monitoring) and Section VII (Stream
Water Quality, Macroinvertebrate, and Fish Monitoring) are not applicable to Headwater Streams.
Instead, these systems will be subject to the monitoring and performance standards identified
below:
A. Headwater Stream Monitoring Requirements
1. Proposals to use the Headwaters Stream Guidance must include justification within the
Mitigation Plan that documents the site conditions and supports the use of this
approach. This should include catchment size, slope, soil type, and valley length for all
channels. In general, catchments of less than 25 acres may not be appropriate for
stream credit using this approach. Credit must be calculated using valley length, not
stream centerline (thalweg) measurements. Wetland credit, if proposed in conjunction
with the stream project, cannot be generated within the 100-foot corridor where the
stream is expected to develop.
2. Headwater stream monitoring must be conducted for 7 years, with monitoring events
occurring every year as described below.
3. Surface water flow should be documented using gauges (flow meters, pressure
transducers, etc.), or automated photo loggers. Gauge stations should be located
within the anticipated primary path of flow within the low point of the valley to ensure
all flow events are captured. Gauge stations should also be placed along the
topographic low point of the valley as necessary to document the upstream end of
channel forming flows. The number of gauge stations to be installed should be based
on relevant factors, including pre and post-construction site conditions, valley slope and
length, watershed size, adjacent wetlands, etc., and should be sufficient to document
the upper end of stream formation when considered with the required field indicators
listed in the performance standards (see Section VIII(B) below).
4. Channel formation within the valley or crenulation must be documented through the
identification of field indicators consistent with those listed in RGL 05-05. Identified
field indicators (listed in the performance standards below) must be documented using
data sheets and photographs, and their location must be shown on a plan view of the
site to be included with the annual monitoring report. Additional monitoring and/or
analysis may be necessary in the event of abnormal climactic conditions.
B. Headwater Stream Performance Standards
1. Continuous surface water flow within the valley or crenulation must be documented to
occur every year for at least 30 consecutive days during the prescribed monitoring
period. Additional monitoring may be required if surface water flow cannot be
documented due to abnormally dry conditions.
13
2. Channel formation must be documented using indicators consistent with RGL 05-05 in
accordance with the following schedule:
a. During monitoring years 1 through 4, the preponderance of evidence must
demonstrate a concentration of flow indicative of channel formation within the
topographic low-point of the valley or crenulation as documented by the following
indicators:
• Scour (indicating sediment transport by flowing water)
• Sediment deposition (accumulations of sediment and/or formation of
ripples)
• Sediment sorting (sediment sorting indicated by grain-size distribution
within the primary path offlow)
• Multiple observed flow events (must be documented by gauge data and/or
photographs)
• Destruction of terrestrial vegetation
• Presence of litter and debris
• Wracking (deposits of drift material indicating surface water flow)
• Vegetation matted down, bent, or absent (herbaceous or otherwise)
• Leaf litter disturbed or washed away
b. During monitoring years 5 through 7, the stream must successfully meet the
requirements of standard 2(a) above and the preponderance of evidence must
demonstrate the development of stream bed and banks (i.e., an ordinary high
water mark) as documented by the following indicators:
• Bed and banks (may include the formation of stream bed and banks,
development of channel pattern such as meander bends and/or braiding at
natural topographic breaks, woody debris, or plant root systems)
• Natural line impressed on the bank (visible high water mark)
• Shelving (shelving of sediment depositions indicating transport)
• Water staining (staining of rooted vegetation)
• Change in plant community (transition to species adapted for flow or
inundation for a long duration, including hydrophytes)
• Changes in character of soil (texture and/or chroma changes when
compared to the soils abutting the primary path of flow)
IX. Wetland Hydrology Monitoring
The purpose of this section is to provide guidance and requirements for a number of aspects of
wetland hydrology monitoring and performance criteria. The fundamental goal of a monitoring
program is to provide reliable data upon which valid conclusions can be reached regarding the
success or failure of a mitigation site. While wetland hydrologic performance criteria will be
discussed in this section, other related aspects of wetland hydrology will be covered, such as issues
related to growing season and the proper installation and placement of groundwater monitoring
gauges. Some concepts that are important to the discussion about wetland hydrology are included
below:
14
Hydrologic regime - The distribution and circulation of water in an area on average during a
given period including normal fluctuations and periodicity
Hydrologic performance standards - The criteria set forth within a compensatory mitigation
plan that describes the specific hydrologic regime that will exist on a site and the subsequent
achievement of that specific goal.
A. Requirements for Monitoring Hydrology and Reporting Hydrologic Data
Wetland hydrology monitoring must be conducted for 7 years, with monitoring events
occurring every year as described below. For non-forested coastal marsh wetlands,
monitoring will generally only be required for 5 years.
2. Water table depths beneath the soil surface should be recorded at least once per day.
Two or more measurements per day may be required ifthe data will be used to calibrate
hydrologic models.
Detailed soil profile descriptions should be recorded for each boring where a gauge is
installed. These profile descriptions should be a record ofthe soil horizons present, and
the color, texture, and redoximorphic features present should be described following
standard procedures as specified by the USDA-NRCS (Schoeneberger et al., 2002).
4. Wetland groundwater gauges must be installed in accordance with the techniques and
standards described in the USACE document entitled "Technical Standard for Water-
Table Monitoring of Potential Wetland Sites" (ERDC TN-WRAP-05-2, June 2005)
available on the Wilmington District's Regulatory In-lieu Fee and Bank Information
Tracking System (RIBITS) website. In particular, bentonite seals must be installed and
properly maintained on all wells. Deeper well depths (4'-5') are also recommended to
help interpret fluctuations in the water table, provided that wells do not penetrate any
restrictive soil horizons. Routine well maintenance should be documented in annual
monitoring reports.
A sufficient number of gauges must be installed to adequately characterize the different
soils, vegetation communities, and surface topographic variations that are found across
the site. Areas in the center of the wetland and at the edge must be monitored. It may
be most efficient to install gauges in transects that extend from the wetland center to
edge. Gauges must not be installed in localized depressions that are not representative
of surrounding site conditions.
Each gauge location should have recorded GPS coordinates and elevation at ground
level (msl), which should match the calibration level of the gauge. If there is an offset,
it must be reported in the monitoring report. If the offset changes over the course of
monitoring, the change and reason should be documented in the mitigation plan (e.g.,
floodplain sediment accumulation).
15
7. In order to minimize the risk of credit loss during close-outs, gauges must be installed
in transects extending away from any perimeter drainage features that may remain
after the site is constructed.
8. When hydrology data is reported it should include a summary table that includes all the
gauges and the number of days of saturation and percent hydroperiod. In addition,
each monitoring year should include data from all previous monitoring years.
9. Every gauge in each monitoring report should have a representative graph showing the
water table levels with a reference line at 12 inches below the surface.
10. In each monitoring report (where hydrologic data is required) there should be an
explanation or graphical representation that explains/portrays whether the site had an
above, below, or normal precipitation year.
11. The growing season should be stated (start date, end date, and number of days) and
the method used to determine the extent should be explained (see Section IX(B) below).
B. Target Wetland Hydrology Related to Precipitation and Growing Season
Precipitation
Hydrological data should be placed in the context of normal, wetter than normal, and
drier than normal, precipitation based on the most recent 30-year period of record. The
WETS table from the weather station closest to the compensation site can be used for
this purpose (Eggers, 2012). The USACE has summarized the principle methods for
assessing normal rainfall conditions at (Sprecher and Warne, 2000), which is available
on Wilmington District's RIBITS website. Rainfall should be measured on-site to
determine whether the water table requirements for wetland hydrology have been met
during periods of normal or drier than normal rainfall. Other recommendations from
Wetland Hydrology Assessment, Vepraskas, et al., 2013:
• Rainfall should be measured on-site using at least one recording rain gauge.
• Rainfall from the nearest available weather station can be used to supplement
data collected on-site, or may be utilized in place of collecting on site if the station
is located close to the project.
• Normal rainfall conditions may be assessed for the 3 month period that comes
prior to the time when the water table rises above the 12 inch depth during the
growing season (Sumner, et al., 2009).
Growing Season
For compensatory mitigation, the hydrology present during the growing season is the
general standard for wetland hydrologic monitoring. The growing season information
can be derived from County Soil Survey data and/or the USACE Regional Supplements
(Atlantic and Gulf Coastal Plain Region, 2012, Eastern Mountains and Piedmont Region,
2012). In addition, the growing season will occur for the period identified on the WETS
data tables for a probability of 50% and an air temperature of 28 °F. These growing
season dates are available for all counties in NC. While other definitions of growing
16
season are in use, this definition has, until recently, been used by the US Army Corps of
Engineers to assess wetland hydrology nationwide.
The USACE Regional Supplements that apply in North Carolina allow for the two
different methods to determine growing season, one is soil temperature, and the other
is vegetative indicators. While the Regional Supplement supports soil temperature as
a growing season determinant, the NCIRT cautions any provider which lengthens the
growing season due to soil temperatures. The fundamental purpose of the growing
season is related to the hydrology being present during the time of year the soil
microbes are most active. Based on evidence in the literature (Skaggs, 2012), the longer
a growing season is extended, even out to 365 days, the more marginal wetlands fail to
obtain basic wetland hydrologic requirements. If soil temperature monitoring is
proposed as the method to determined growing season, justification must be provided
in the mitigation plan. Soil temperatures should also be measured using a continuous
measurement device, if possible. Additionally, this method should also be corroborated
with vegetative indicators, including bud burst and leaf drop. In general, growing
seasons that start earlier than March 15t or end later than November 20t" may not be
approved, depending upon project location.
C. Establishment of Wetland Hydrologic Performance Criteria
1. Percent Saturation/Hydroperiod Thresholds for Common Wetland Soil Series in North
Carolina
The NCIRT has established saturation/hydroperiod thresholds for wetland restoration
performance criteria in North Carolina. These thresholds/ranges are provided in Table
1, below. The Wetland Saturation Threshold Table lists many common soil series in
each major physiographic region of North Carolina and their requisite percent
saturation range for the growing season. If data is available to support a reduced
hydroperiod, that data must be provided in the mitigation plan.
2. Hydrologic Variance for Extensively Managed Hydric Soils
Much of a site's ability to reach and maintain its appropriate saturation period is
dependent upon the soil conditions, most notably; organic matter, clay content, and
soil structure. If the site has been extensively managed, the NCIRT may consider a
short-term wetland hydrologic variance for the site.
The NCIRT will consider shortening the saturation period for soils on extensively
managed sites for up to 2% for the first two years of monitoring (for example, a Rains
soil series calls for a range of hydrology of 10-12% in the Wetland Saturation Threshold
Table, then the NCIRT may allow for an 8% target saturation period for Monitoring years
1 and 2). However, at Monitoring Year 3 the NCIRT will expect the minimum target of
the hydrology range to be achieved. Generally, a variance may only be approved when
supporting documentation justifies the extensive management of a site in the
mitigation plan (site history, existing condition photographs, etc.).
17
3. Some common Hydric Soil Series and their taxonomic subgroups are provided in
this document; if a series you are looking for is not provided, it can be accessed on the
Natural Resources Conservation Service Official Soil Series Descriptions webpage. If the
required saturation range for a soil series is not listed in the Wetland Saturation
Threshold Table, the following procedure should be used:
a. Look up the taxonomic subgroup of the Soil Series at the link above.
b. If the series has the same taxonomic subgroup name as another series that
is listed, then that which is listed is the required hydrology range. (For
example, if you have a site with soils mapped as Woodington, you will
notice it is not listed in Table 1; however, if you go to the link above, you
will find that it has the same taxonomic name as a Rains which is listed,
therefore the required hydroperiod range would be 10-12% of the growing
season.)
c. If the soil series is neither in Table 1, nor has a taxonomic name which
matches any other listed, the District, in consultation with the NCIRT, must
approve the proposed wetland saturation range.
D. Reference Data - Modeling Wetland Hydrology
If a Provider believes a different hydrology standard is appropriate for their site, they may
utilize several/different data sources to support their position. This could include reference
data and/or wetland hydrology models. Reference data may be utilized to support, but not
take the place of, wetland performance criteria. It is likely that as more data is collected, the
ranges that appear in the Wetland Saturation Threshold Table will change. Firms that monitor
a large number of wetland mitigation sites for mitigation banks or the NCDMS have a
considerable amount of data or historical knowledge of wetland hydroperiods. Both the
NCDMS and North Carolina State University are working on wetland hydrology databases,
which in the near future, should inform the mitigation community further with regard to
wetland hydroperiod performance criteria.
Groundwater models may be utilized for predicting future hydro periods of a wetland
restoration site. However, modeling data alone will not be used as the primary information
source for determining hydrologic success. Any model data must be corroborated with
groundwater wells. "The best use of simulation models for evaluating success of a restored
site is to use them in combination with water table data" (Vepraskas, et. al., 2013).
E. Chewacla Soils
Chewacla is a non-hydric soil series that appears on many floodplains in the upper Coastal
Plain and Piedmont of North Carolina, and depending on site characteristics has been
considered for many wetland restoration projects. This series, as evidenced by its taxonomic
subgroup (Fluvaquentic Dystrudepts), has inclusions of hydric soils. The NCIRT would like to
stress that although these sites may yield wetland credit, often the project success is due to
particular site conditions (for example, extensive ditching, or toe-or-slope geomorphic
landscape position) that actually result in more of a hydric localized soil condition or series
(such as Wehadkee-Typic Fluvaquent). The NCIRT emphasizes that it is imperative that all soil
mapping be verified by a North Carolina Licensed Soil Scientist.
18
Table 1- Wetland Saturation Threshold Table
Common Coastal Plain Soil Series (associated with wetlands)
Wetland
Saturation
Series Name Taxonomic Subgroup Range
Altavista" Fine-Loamy, Mixed, Semiactive, Thermic Aquic Hapludults 6-8%
Arapahoe Coarse-Loamy, Mixed, Semiactive, Nonacid, Thermic Typic Humaquepts 12-16-%
Augusta Fine-Loamy, Mixed, Semiactive, Thermic Aeric Endoaquults 7-9%
Belhaven Loamy, Mixed, Dysic, Thermic Terric Haplosaprists 20%
Bibb Coarse-Loamy, Siliceous, Active, Acid, Thermic Typic Fluvaquents 12-16-%
Chastain Fine, Mixed, Semiactive, Acid, Thermic Fluvaquentic Endoaquepts 12-16-%
Craven� Fine, Mixed, Subactive, Thermic Aquic Hapludults 6-8%
Croatan Loamy, Siliceous, Dysic, Thermic Terric Haplosaprists 20%
Dare Dysic, Thermic Typic Haplosaprists 25%
Grifton Fine-Loamy, Siliceous, Semiactive, Thermic Typic Endoaqualfs 10-12%
Hyde Fine-Silty, Mixed, Active, Thermic Typic Umbraquults 12-16-%
Johnston Coarse-Loamy, Siliceous, Active, Acid, Thermic Cumulic Humaquepts 12-16-%
Leaf Fine, Mixed, Active, Thermic Typic Albaquults 10-12%
Lenoir Fine, Mixed, Semiactive, Thermic Aeric Paleaquults 7-9%
Leon Sandy, Siliceous, Thermic Aeric Alaquods 7-9%
Lynn Haven Sandy, Siliceous, Thermic Typic Alaquods 10-12%
Masontown Coarse-Loamy, Siliceous, Active, Nonacid, Thermic Cumulic Humaquepts 12-16-%
Meggett Fine, Mixed, Active, Thermic Typic Albaqualfs 10-12%
Murville Sandy, Siliceous, Thermic Umbric Endoaquods 12-16-%
Pactolus' Thermic, Coated Aquic Quartzipsamments 6-8%
Pantego Fine-Loamy, Siliceous, Semiactive, Thermic Umbric Paleaquults 12-16-%
Portsmouth Fine-Loamy Over Sandy Or Sandy-Skeletal, Mixed, Semiactive, Thermic 12-16-%
Typic Umbraquults
Rains Fine-Loamy, Siliceous, Semiactive, Thermic Typic Paleaquults 10-12%
Roanoke Fine, Mixed, Semiactive, Thermic Typic Endoaquults 9-12%
Tomotley Fine-Loamy, Mixed, Semiactive, Thermic Typic Endoaquults 10-12%
Torhunta Coarse-Loamy, Siliceous, Active, Acid, Thermic Typic Humaquepts 12-16-%
19
Table 1- Wetland Saturation Threshold Table, Continued
Common Piedmont Soil Series
Wetland
Saturation
Series Name Taxonomic Subgroup Range
Chewacla" Fine-Loamy, Mixed, Active, Thermic Fluvaquentic Dystrudepts 10-12%
Wehadkee Fine-Loamy, Mixed, Active, Nonacid, Thermic Fluvaquentic Endoaquepts 12-16-%
Iredell� Fine, Mixed, Active, Thermic Oxyaquic Vertic Hapludalfs 6-8%
Kinkora Fine, Mixed, Semiactive, Mesic Typic Endoaquults 10-12%
Riverview� Fine-Loamy, Mixed, Active, Thermic Fluventic Dystrudepts 7-9%
Hatboro Fine-Loamy, Mixed, Active, Nonacid, Mesic Fluvaquentic Endoaquepts 12-16-%
Worsham Fine, Mixed, Active, Thermic Typic Endoaquults 10-12%
Helena` Fine, Mixed, Semiactive, Thermic Aquic Hapludults 6-8%
Congaree` Fine-Loamy, Mixed, Active, Nonacid, Thermic Oxyaquic Udifluvents 7-9%
Meggett Fine, Mixed, Active, Thermic Typic Albaqualfs 10-12%
Coxville Fine, Kaolinitic, Thermic Typic Paleaquults 10-12%
Dorian" Fine, Mixed, Semiactive, Thermic Aquic Hapludults 6-8%
Oakboro*' Fine-Loamy, Mixed, Active, Thermic Fluvaquentic Dystrudepts 10-12%
Cordorus"` Fine-Loamy, Mixed, Active, Mesic Fluvaquentic Dystrudepts 7-9%
Common Mountain Soil Series
Alarka Fine-Loamy Over Sandy Or Sandy-Skeletal, Mixed, Active, Mesic Aeric 7-9%
Epiaquults
Nikwasi Coarse-Loamy Over Sandy Or Sandy-Skeletal, Mixed, Superactive, 12-16-%
Nonacid, Mesic Cumulic Humaquepts
Rosman` Coarse-Loamy, Mixed, Superactive, Mesic Fluventic Humudepts 10-12%
Toxaway Fine-Loamy, Mixed, Superactive, Nonacid, Mesic Cumulic Humaquepts 12-16-%
Ela Coarse-Loamy, Siliceous, Superactive, Acid, Mesic Fluvaquentic 12-16-%
Humaquepts
Reddies� Coarse-Loamy Over Sandy Or Sandy-Skeletal, Mixed, Superactive, Mesic 10-12%
Oxyaquic Humudepts
Arkaqua�` Fine-Loamy, Mixed, Active, Mesic Fluvaquentic Dystrudepts 7-9%
Wesser Sandy-Skeletal, Mixed, Mesic Humaqueptic Fluvaquents 12-16%
Biltmore� Mixed, Mesic Typic Udipsamments 7-9%
�These soil series are non-hvdric soils that mav aopear in close association with other soil series that are
hydric.
�"These soil series are all non-hydric soils that are similar taxonomically to the Chewacla soil series.
It should be noted that the presence of non-hydric series in this Table does not mean the NCIRT
endorses pursuing sites with these soils series for wetland mitigation. The soils identified with asterisks
are non-hydric soils. These soils often appear in association with other soils which are hydric. To
determine whether the soil on site is in fact the mapped soil series, you should consult a North Carolina
Licensed Soil Scientist.
20
X. Visual Monitoring
The following requirements apply to all wetland and stream mitigation projects, including
preservation areas as noted below. The goal of visual monitoring is to provide a method that rapidly
identifies any concerns on a mitigation project that may not be picked up by other routine
monitoring activities. These include encroachments, areas with poor vegetation growth, beaver
activity, excessively or inadequately drained areas, stream bank instability, etc. Visual monitoring
is intended to cover the entire mitigation site in an efficient manner. This information should be
presented as a current conditions plan view that identifies all problems with the site. The following
requirements apply to visual monitoring:
A. Visual monitoring of all portions of the mitigation project should be conducted annually and
be provided in the monitoring report in a plan view format. Visual monitoring should be
conducted by traversing the entire mitigation site to identify and document areas of low stem
density or poor plant vigor, areas dominated by undesirable volunteer species, prolonged
inundation, native and exotic invasive species, beaver activity, herbivory, encroachments,
indicators of livestock access, or other areas of concern.
B. The results of visual assessments must be included in the Annual Monitoring Report, and
should identify the date(s) that the assessment was conducted. In general, it is preferable for
the visual assessment of the site to be performed toward the end of the monitoring year. A
narrative of the results should be included in the Annual Monitoring Report to describe any
areas of concern, and should be represented on the current conditions plan view of the site
with GPS coordinates provided in decimal degrees. Photographs showing the features of
concern are helpful. Once a feature of concern has been identified, that same feature must
be reassessed on all subsequent visual assessments until the issue has been corrected.
Photographs should be taken from the same location year-to-year to document the current
condition of the concern. The Monitoring Report should identify all recommended courses
of action, which may include continued monitoring, repair or other remedial action to
alleviate the concerns.
C. For stream projects, visual monitoring within the channel corridor should be conducted along
the entire length of each reach to identify and document movement of the channel pattern,
dimension or profile (e.g., lateral bank migration, bank instability, instability/failure of in-
stream structures, structure piping, headcuts, aggradation/excessive sediment deposition,
etc.), beaver activity, excessive live stake mortality, invasive species, or other potential
problems with the channel. As discussed earlier, stream bank instability identified through
visual monitoring should be followed up with installation of bank pins, unless it is not possible
to do so. Visual monitoring of streams should be conducted only by individuals that have the
appropriate training and/or expertise to assess the stability of streams and the condition of
in-stream structures.
D. Within preservation areas, visual monitoring should be conducted annually until project
closeout for the purpose of ensuring that no activities are occurring that are in violation of
the restrictions included in the preservation mechanism prior to the site being transferred to
the long-term steward.
21
XI. Stream Buffers
Vegetated buffers are a critical component of all stream mitigation projects. In 2003, the District
established a standard buffer width of 30 feet in the mountain counties, and 50 feet in all other
counties. This guidance provides additional clarification regarding these requirements, and also
establishes a methodology for assessing credit adjustments for streams that have buffers that are
wider or narrower than the standard width. This guidance builds on the most recent draft guidance
that was released for public comment in July, 2010.
A. Required Minimum Buffer Widths
1. The riparian buffer requirement for stream and stream/wetland mitigation projects is
a minimum of 30 feet for the mountain counties and 50 feet for all other counties.
2. This distance is measured horizontally from the normal wetted perimeter of the stream
channel to the nearest edge of the wooded buffer on the same side of the channel. The
wooded buffer is defined as the edge of the contiguous riparian zone along a stream
that is vegetated with appropriate species, whether planted or preexisting, and located
within the boundary of the preservation mechanism. In cases where an approved
mitigation plan includes non-tree species in the planting plan, the wooded buffer would
include areas planted with these species as well. For multi-thread channels, the wetted
perimeter includes all channels and is measured from the outer-most edge of the
channel on each side of the valley. Where utility corridors run parallel with stream
channels, the buffer may continue across the utility corridor if the corridor is fully
vegetated (i.e., no paved or other impervious trails or structures - maintained
herbaceous cover and unpaved foot paths are acceptable), there are no berms, ditches
or other features that prevent sheet flow of water from one side of the easement to
the other, and the inner edge of the utility corridor is located at least 15 feet from the
wetted perimeter of the stream and no more than 15 feet in total width. In these cases,
the width of the utility corridor cannot be included in the measurement of the overall
wooded buffer width. Utility corridor width is measured by the width of the utility
easement or the area that has historically been maintained in cases where there is no
utility easement.
3. While the minimum acceptable width is measured from the normal wetted perimeter,
it is preferred that buffers are established that meet these same widths as measured
from the edge of the meander belt to ensure that streams have adequate space to
migrate within the buffer. This also allows for a straighter edge along the buffer, which
is preferred to a project boundary that meanders with the channel.
4. Depending on project limitations, buffers that are less than the minimum width stated
above may be approved on a case-by-case basis by the District, in consultation with the
NCIRT. In these cases, the mitigation plan must clearly show where the buffers will not
meet this standard and explain why the minimum width cannot be met (e.g., limited
property availability, existing utility easements, etc.). The credit generated by reaches
with less than the minimum buffer width will generally be reduced in accordance with
22
the procedures outlined in Section XI(C). Exceptions to this may be approved on a case-
by-case basis in urban areas or other situations where it is not practicable to obtain
sufficient land; however, the mitigation plan must demonstrate how these project will
provide optimal functional uplift to targeted stream functions despite the presence of
reduced buffers. The addition of stormwater controls or other BMPs to control and/or
treat runoff from contributing watersheds with high percentages of impervious cover is
an example of an action that may justify full credit in urban systems.
Where streams intersect with project boundaries (e.g., property lines, farm crossings,
utility easements, etc.), it may not be possible for buffers to meet the minimum
standard width all the way to the end of the channel where the intersection occurs at
an acute angle. Because of this, exceptions to the minimum width are allowable
without credit reduction when no more than 5% of the total project stream length,
measured cumulatively, is located in these areas. Efforts should be made to acquire
the necessary property rights to ensure minimum acceptable buffers are established in
as short a distance as possible.
Where farm crossings, utility lines, or other stream crossings are proposed in mitigation
plans, they should be minimized to the maximum extent practicable. Crossings should
be co-located whenever possible, and situated at the beginning or end of a stream reach
rather than in the middle. Additionally, they should cross perpendicular to the stream
channel. All stream crossings, to include aerial and buried utility lines, are not eligible
to generate stream credit within the limits of the crossings (as defined by the utility
easements for utility crossings). Stream reaches immediately adjacent to crossings that
intersect at acute angles may also be subject to credit reduction due to narrow buffers
that result, except as allowed in parts 2 and 5 above.
Other than the exceptions noted in part 4 and 5 above, stream channels with buffers
less than 15 feet in total width on either side are not eligible to receive mitigation credit
(on either side of the channel).
B. Additional Credit for Buffers Exceeding Minimum Standard Widths
To provide an incentive for buffers that exceed the minimum standard width, additional
credit may be awarded using the procedures outlined in Section XI(C) below. Additional
credit is not provided until buffer widths exceed 50 feet from the normal wetted
perimeter for mountain streams and 75 feet from the normal wetted perimeter for
piedmont and coastal plain streams.
The following guidelines apply to the addition of credit due to wider buffers:
Buffer measurements for additional credit must be made horizontally, beginning
from the edge of the wetted perimeter and extending to the nearest edge of the
wooded buffer (as defined in XI(A)(2)) in any direction. Buffers must also be
located within the watershed draining to the stream. An average stream width
may be applied to a surveyed stream centerline to estimate the normal wetted
perimeter. Measurements may not cross over any breaks within the buffer, such
as utility lines, other streams, roads, greenways, or other easement breaks, even
23
if located within the project boundary, except as specified in Section XI(A)(2). For
constructed multi-thread streams, the buffer should be measured from the edge
of the wetted perimeter of the outer-most thread. (This does not refer to
channels restored using the Headwater Stream Guidance discussed in Section
VIII, which are not eligible to generate additional credit for wider buffers.)
b. The inclusion of any buffer for additional credit is dependent upon the success of
vegetation plantings - areas that are bare or dominated by invasive species may
be eliminated from additional credit calculations.
c. Any area within a buffer may only be used to provide additional credit for one
stream (i.e., where wide buffers exist between two project streams, or leading up
to the confluence of two streams, these areas may only be used to provide
additional credit for one of the streams).
d. Due to the minimum required widths, additional credit cannot be generated until
a stream is at least 75 feet inside the edge of the buffer (50 feet for mountain
counties). This distance assumes the stream intersects the buffer at a
perpendicular angle, and will increase where the intersection is at an acute angle.
Where a stream origin is located within a project, that origin must be at least 75
feet inside the edge of the buffer (50 feet for mountain counties).
e. To qualify for additional credit, channels must be jurisdictional. Additional credit
may be awarded for both perennial and intermittent reaches, and also for
restoration or enhancement reaches, but not for any preservation reach (buffer
width is already considered when determining the acceptability and appropriate
mitigation ratios for preservation reaches).
f. Areas within mitigation projects that are used to generate additional credit must
be used exclusively for the generation of stream mitigation credits, and cannot
be used for the generation of any other credit type (i.e., the same square foot of
buffer cannot be used to generate wetland credit, or credits associated with other
federal, state, or local requirements, including nutrient offset credits or state
buffer credits).
g. Where additional credit is proposed for wider buffer widths, the mitigation plan
must include a plan view that details the individual reaches associated with each
buffer width category shown in the tables in part C. The plan view should identify
the normal wetted perimeter and the edge of the wooded buffer, and should be
to scale so that the measurements can be verified. Additionally, the calculations
must be presented in a table that shows the length of each reach and the
associated credit increase resulting from the wider buffers.
C. Procedures to Calculate Credits for Non-standard Buffer Widths
1. In order to calculate credit adjustments due to non-standard buffer widths, each side
of the stream must be evaluated separately. The two sides of each stream should be
broken down into reaches that fall within the buffer width categories shown in Table 2
24
below. Measurements are made using the nearest point method described in Section
XI(B)(2) above (the nearest buffer edge may be in any direction, not necessarily
perpendicular from the centerline of the stream). Measurements may be calculated
using any method (e.g., GIS, CAD, by hand using a scale, etc.), provided that the plan
view and calculations are provided. The lengths of individual reaches should then be
multiplied by the mitigation ratio to yield stream credits, and the results should then be
adjusted by the increase or decrease percentage indicated in Table 2. Finally, the
resulting credit amounts should be totaled for each side of the stream. The sum of both
sides of the stream is then divided by two to yield the final number of credits.
Table 2- Stream Mitigation Credit Adjustments for Non-standard Buffer Widths
Mountain Counties Piedmont and Coastal Plain Counties
Buffer Width Adjustment to guffer Width Adjustment to
Stream Credit Stream Credit
Less than 15 feet -100 % Less than 15 feet -100%
15 to < 20 feet -50 % 15 to < 20 feet - 50%
20 to < 25 feet -30 % 20 to < 25 feet -40%
25 to < 30 feet -15 % 25 to < 30 feet - 30%
30 to < 50 feet 0% 30 to < 35 feet -20%
50 to < 75 feet +9 % 35 to < 40 feet -15%
75 to < 100 feet +16 % 40 to < 45 feet -10%
100 to < 125 feet +22 % 45 to < 50 feet -5%
125 to < 150 feet +27 % 50 to < 75 feet 0%
150 feet or Greater +30 % 75 to < 100 feet +7%
100 to < 125 feet +12%
125 to < 150 feet +16%
150 feet or reater +20%
XII. Remedial Actions
Mitigation Plans are required to include an Adaptive Management Plan, which should address how
problems on sites will be resolved. In addition, if monitoring results indicate that all or some portions of
the site will fail to meet one or more of the required performance standards, the monitoring report must
provide a remedial action plan (based on the Adaptive Management Plan) to address the deficiency and
the USACE mitigation contact shall be notified as soon as possible if a situation is discovered that will
require remedial action. The remedial action plan, at a minimum, must describe the failure, the source
or reason for the failure, a concise description of the corrective measures that are proposed, and a time
frame for the implementation of the corrective measures. Additional monitoring, as prescribed by this
guidance, may also be required.
A. Vegetation
If monitoring indicates that portions of the site are not going to meet required vegetation
performance standards, replanting of all or part of the site may be required. If supplemental
plantings are required by the NCIRT that exceed 20% of the total planted area of the site (measured
cumulatively), additional monitoring may be required within these areas to demonstrate success in
accordance with the vegetation performance standards. Remedial action plans should take into
25
account reasons for failure and provide for corrective measures if applicable. For instance, if
inundation is determined to be a cause for poor vegetation performance, the replanted species may
be adjusted to include species more tolerant to inundation.
In the event that a site is not meeting the vegetation vigor standards, the remedial action plan
should seek to identify the cause of the problem and remediate the problem if possible. This may
include one or more of several options, such as deep ripping portions of the site and replanting,
mowing, herbicide use or other treatment of competitive and/or invasive vegetation to release the
desirable species, fertilization, beaver control, or replanting with species less subject to herbivory.
In certain instances, it may be determined that it is not practicable to perform remedial actions to
address the factors limiting the vigor of planted vegetation, and that no further work will improve
the conditions. In this situation, the NCIRT will determine what level of credit may be generated by
portions of the site that are not meeting performance standards.
B. Stream Stability
Stream stability may be identified as a concern with stream mitigation projects even though all
performance standards may be met at monitored cross-sections. Visual monitoring of the channel
is intended to identify potential problems that are not captured by cross-sections and allow them
to be tracked and addressed, if necessary. The use of bank pins may be prescribed to help track
bank stability. In general, repairs should be undertaken when stream stability issues are identified
that continue to worsen, pose a threat to other portions of the stream (headcuts), or are systemic
and symptomatic of more serious issues with the design and/or construction of the project.
Moreover, the NCIRT recommends that if a reach has greater than 10% bank or bed instability, then
it is likely the reach may be a candidate for repair. If this number exceeds 15%, it is highly likely that
the stream reach will need repair or it may be a threat to other portions of the project if not
addressed. If problems continue to persist, repairs may be discontinued and mitigation credits will
be adjusted accordingly. These decisions will be made on a case-by-case basis by the NCIRT.
C. Invasive Species
As more stream and wetland mitigation projects have been established, problems with native and
exotic invasive vegetation or otherwise undesirable plant species have become more prevalent. A
list of these species is available as an appendix to the NC SAM User's Manual available on the
Wilmington District RIBITS website. The current approach used by the District is to manage invasive
species during the monitoring phase of mitigation projects, with the understanding that long-term
management of invasive species in perpetuity is not practicable. The District also expects that
invasive species management will always be a routine maintenance task for compensatory
mitigation sites; however, removal of invasive species should not typically be identified as a primary
source of functional improvement in the Mitigation Plan. In rare cases, credit may be provided for
invasive species management activities, but in these cases, the functional uplift from the
management activities should be explained in the mitigation plan and a long-term management
plan and appropriate funding may be required.
No specific performance standards have been established in this guidance for controlling invasive
species, although sites should be routinely monitored for the presence of invasive species during
both the visual assessments of the channel and vegetation plot monitoring events. In general, when
an invasive species impacts the functional integrity of the target vegetative community, adaptive
26
management aimed at controlling the species should be conducted. In certain cases, credit releases
may be withheld or modified until the problem is addressed.
Although a site may rapidly be dominated by one or more invasive species, the desirable or planted
species may have survived and exhibited sufficient growth to suggest that they will continue to
survive. Efforts should be taken immediately upon the identification of invasive species on the site
to eradicate or at least control their recurrence, and may include chemical or physical eradication
methods. In cases where invasive species located on an adjacent property threaten a mitigation
site, it is recommended that the control measures be extended to the adjacent property if the
landowner is willing. Extreme care must be exercised such that the desirable species are not
adversely impacted. Efforts taken to control invasive species must always be noted in the
monitoring reports.
D. Beaver
The occurrence of beavers on stream and wetland mitigation projects has become prevalent
throughout NC, but this is a natural and expected occurrence within these communities. Beaver
management is a topic that should be addressed in the Adaptive Management Plan portion of all
Mitigation Plans. When beaver activity is discovered on a mitigation site, the monitoring report
should document the location of dams in the current conditions plan view. The report should also
include an estimate of the potential impact of the beaver and dams to the site (e.g., LF of stream
impounded, acres of wetlands flooded).
When management is prescribed, it may entail trapping or otherwise removing beavers from
mitigation sites and completely removing any beaver dams. All management activities should be
tracked and included in the monitoring reports. This should include dates of trapping, number of
beavers removed, and the number and location of dams that are removed. Generally, dams should
be removed by hand whenever possible. Depending on the method of dam removal (e.g.,
mechanical, explosives, etc.), it may be necessary to obtain a DA permit from the USACE county
Project Manager prior to conducting the work.
XIII. Monitoring Schedule
Table 3 lists the monitoring requirements for each year. Monitoring events conducted after year 7 will be
specified on a case-by-case basis by the NCIRT. Stream mitigation conducted in accordance with the
Headwater Stream Guidance will be monitored following the schedule outlined in Section VIII. Wetland
hydrology monitoring activities listed below should be conducted in accordance with the approved
Mitigation Plan. Please note that the table below is a general list of monitoring requirements, and is not
meant to be a comprehensive list of monitoring requirements. Individual Mitigation Plans may specify
different monitoring activities and/or schedules.
27
Table 3— Schedule of Monitoring Events
Monitoring Monitoring Activities Required
Event Streams Wetlands
• Water Quality (Section VII(A)) • Per Mitigation Plan
Pre-Construction � Macroinvertebrate & Fish (Section VII(B-C))*
Year 0 • As-built Survey (includes longitudinal profile and • As-built Survey
(As-Built) sampling point locations)
• Vegetation (Section V) • Vegetation (Section V)
• Stream Channel Stability/Hydrology (Section VI) • Wetland Hydrology (Section IX)
Year 1 � Water Quality (Section VII(A))* • Visual, two times (Section X)
• Visual, two times (Section X)
• Vegetation (Section V) • Vegetation (Section V)
• Stream Channel Stability/Hydrology (Section VI) • Wetland Hydrology (Section IX)
Year 2 � Water Quality (Section VII(A))* • Visual, two times (Section X)
• Visual, two times (Section X)
• Vegetation (Section V) • Vegetation (Section V)
• Stream Channel Stability/Hydrology (Section VI) • Wetland Hydrology (Section IX)
Year 3 • Water Quality (Section VII(A))* • Visual, two times (Section X)
• Macroinvertebrate & Fish (Section VII(B-C))*
• Visual, two times (Section X)
• Water Quality (Section VII(A)) * • Visual (Section X)
Year 4 � Visual, two times (Section X) • Wetland Hydrology (Section IX)
• Vegetation (Section V) • Vegetation (Section V)
• Stream Channel Stability/Hydrology (Section VI) • Wetland Hydrology (Section IX)
Year 5 • Water Quality (Section VII(A)) * • Visual, two times (Section X)
• Macroinvertebrate & Fish (Section VII(B-C)) *
• Visual, two times (Section X)
• Water Quality (Section VII(A)) * • Wetland Hydrology (Section IX)
Year 6 . Visual, two times (Section X) • Visual, two times (Section X)
• Vegetation (Section V) • Vegetation (Section V)
• Stream Channel Stability/Hydrology (Section VI) • Wetland Hydrology (Section IX)
Year 7 • Water Quality (Section VII(A)) * • Visual, two times (Section X)
• Macroinvertebrate & Fish (Section VII(B-C)) *
• Visual, two times (Section X)
*Indicates optional monitoring activities
XIV. Credit Release Schedules
The standard release schedule for mitigation bank and ILF credits generated through stream and wetland
mitigation projects has been modified to meet the new standards for the monitoring timeframes provided
in this guidance document. For mitigation banks, the first credit release (15% of the bank's total stream
restoration and/or enhancement credits) will occur upon establishment of the mitigation bank, and upon
completion following criteria:
1) Execution of the MBI or UMBI by the Sponsor and the USACE
2) Approval of the final Mitigation Plan
28
3) The mitigation bank site must be secured
4) Delivery of the financial assurances described in the Mitigation Plan
5) Recordation of the long-term protection mechanism and title opinion acceptable to the USACE
6) Issuance of the 404 permit verification for construction of the site, if required.
For mitigation sites that include preservation-only credits, 100% of the preservation credits will be
released with the completion of the six criteria stated above.
For ILF sites (including all NCDMS projects), no initial release of credits (Milestone 1) is provided because
ILF programs utilized advance credits, so no initial release is necessary to help fund site construction. To
account for this, the 15% credit release associated with the first milestone (bank establishment) is held
until the second milestone, so that the total credits release at the second milestone is 30%. In order for
NCDMS to receive the 30% release (shown in the schedules as Milestone 2), they must comply with the
credit release requirements stated in Section IV(I)(3) of the approved NCDMS Instrument.
The following conditions apply to the credit release schedules:
A. A reserve of 10% of a site's total stream credits will be released after four bankfull events
have occurred, in separate years, provided the channel is stable and all other performance
standards are met. In the event that less than four bankfull events occur during the
monitoring period, release of these reserve credits is at the discretion of the NCIRT.
B. For mitigation banks, implementation of the approved Mitigation Plan must be initiated no
later than the first full growing season after the date of the first credit transaction (credit sale).
C. After the second milestone, the credit releases are scheduled to occur on an annual basis,
assuming that the annual monitoring report has been provided to the USACE in accordance
with Section IV (General Monitoring Requirements) of this document, and that the monitoring
report demonstrates that interim performance standards are being met and that no other
concerns have been identified on-site during the visual monitoring. All credit releases require
written approval from the USACE.
D. The credits associated with the final credit release milestone will be released only upon a
determination by the USACE, in consultation with the NCIRT, of functional success as defined
in the Mitigation Plan.
29
The schedules below list the updated credit release schedules for stream and wetland mitigation projects
developed by bank and ILF sites in North Carolina:
Credit Release Schedule and Milestones for Wetlands
Credit Banks ILF/NCDMS
Release Release Activity Interim Total Interim Total
Milestone Release Released Release Released
� Site Establishment (includes all required criteria 15% 15% 0% 0%
stated above)
Completion of all initial physical and biological
2 improvements made pursuant to the Mitigation 15% 30% 30% 30%
Plan
3 Year 1 monitoring report demonstrates that 10% 40% 10% 40%
interim performance standards have been met
4 Year 2 monitoring report demonstrates that 10% 50% 10% 50%
interim performance standards have been met
5 Year 3 monitoring report demonstrates that 15% 65% 15% 65%
interim performance standards have been met
6. Year 4 monitoring report demonstrates that 5% 70% 5% 70%
interim performance standards have been met
� Year 5 monitoring report demonstrates that 15% 85% 15% 85%
interim performance standards have been met
$, Year 6 monitoring report demonstrates that 5% 90% 5% 90%
interim performance standards have been met
9 Year 7 monitoring report demonstrates that 10% 100% 10% 100%
performance standards have been met
*Please note that vegetation plot data may not be required with monitoring reports submitted during
these monitoring years unless otherwise required by the Mitigation Plan or directed by the NCIRT.
Credit Release Schedule and Milestones for Coastal Marsh Wetlands
Credit Banks ILF/NCDMS
Release Release Activity Interim Total Interim Total
Milestone Release Released Release Released
� Site Establishment (includes all required criteria 15% 15% 0% 0%
stated above)
Completion of all initial physical and biological
2 improvements made pursuant to the Mitigation 15% 30% 30% 30%
Plan
3 Year 1 monitoring report demonstrates that 10% 40% 10% 40%
interim performance standards have been met
4 Year 2 monitoring report demonstrates that 15% 55% 15% 55%
interim performance standards have been met
5 Year 3 monitoring report demonstrates that 20% 75% 20% 75%
interim performance standards have been met
6 Year 4 monitoring report demonstrates that 10% 85% 10% 85%
interim performance standards have been met
� Year 5 monitoring report demonstrates that 15% 100% 15% 100%
performance standards have been met
30
Credit Release Schedule and Milestones for Streams
Credit Banks ILF/NCDMS
Release Release Activity Interim Total Interim Total
Milestone Release Released Release Released
� Site Establishment (includes all required criteria 15% 15% 0% 0%
stated above)
Completion of all initial physical and biological
2 improvements made pursuant to the Mitigation 15% 30% 30% 30%
Plan
Year 1 monitoring report demonstrates that
3 channels are stable and interim performance 10% 40% 10% 40%
standards have been met
Year 2 monitoring report demonstrates that
4 channels are stable and interim performance 10% 50% 10% 50%
standards have been met
Year 3 monitoring report demonstrates that
5 channels are stable and interim performance 10% 60% 10% 60%
standards have been met
Year 4 monitoring report demonstrates that
6' channels are stable and interim performance 5% �750��0.� 5% �75��/**�
standards have been met
Year 5 monitoring report demonstrates that
7 channels are stable and interim performance 10% �850��0.� 10% �850�0 .�
standards have been met
Year 6 monitoring report demonstrates that a o
8' channels are stable and interim performance 5% �900/%.� 5% �900���.�
standards have been met
Year 7 monitoring report demonstrates that
9 channels are stable, performance standards 10% �100%") 10% �100%`�)
have been met
*Please note that vegetation data may not be required with monitoring reports submitted during these monitoring
years unless otherwise required by the Mitigation Plan or directed by the NCIRT.
**10% reserve of credits to be held back until the bankfull event performance standard has been met.
31
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33