20141271 Ver 1_Memorandum of Understanding_20110518

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NCDEN6t
North Carolina Department of Environment and Natural Resources
Division of Water Quality
Beverly Eaves Perdue Coleen H. Sullins Dee Freeman
Governor Director Secretary
May 18, 2011
.MEMORANDUM
To: M. Sue Hyde, P.E., Engineering Director, City of Concord
From: Polly Lespinasse, NC Division of Water Quality, Mooresville Regional Office
Subject: Scoping Comments on the Proposed City of Concord's Widening of Derita Road (SR 1445)
between Concord Mills Boulevard (SR 2894) and Poplar Tent Road (SR 1394), STIP Project No. U-
4910, Concord, Cabarrus County
Please reference your correspondence dated May 12, 2011, in which you requested comments for the above referenced
project. An analysis of the project reveals the potential for multiple impacts to jurisdictional streams in the project area.
More specifically, impacts to:
Project Specific Comments:
Rocky River is a Class C, 303(d) Waters of the State. Rocky River is on the 303(d) list for impaired use for aquatic
life due to turbidity. NCDWQ is very concerned with sediment and erosion impacts that could result from this
project. NCDWQ recommends that the most protective sediment and erosion control BMPs be implemented in
accordance with Design Standards in Sensitive Watersheds to reduce the risk of sediment and nutrient runoff to
Rocky River. NCDWQ requests that road design plans provide treatment of the stormwater runoff best
management practices as detailed in the most recent version of NCDWQ Stormwater Best Management Practices.
General Project Comments:
2. The environmental document should provide a detailed and itemized presentation of the proposed impacts to
wetlands and streams with corresponding mapping. If mitigation is necessary as required by 15A NCAC
21-1.0506(h), it is preferable to present a conceptual (if not finalized) mitigation plan with the environmental
documentation. Appropriate mitigation plans will be required prior to issuance of a 401 Water Quality Certification.
3. Environmental assessment alternatives should consider design criteria that reduce the impacts to streams and
wetlands from storm water runoff. These alternatives should include designs that allow for treatment of the storm
water runoff through best management practices as detailed in the most recent version of NC DWQ Stormwater
Best Management Practices, such as grassed swales, buffer areas, preformed scour holes, retention basins, etc.
Mooresville Regional Office _ One
Location: 610 East Center Avenue, Suite 301, Mooresville, NC 28115 NorthCarohna
Phone: [phone]Fax: [phone]\ Customer Service: 1-877-6238748
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Internet: hhoPportal.ncdencom6veblwo
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The Division of Water Quaiity (DWQ) requests that the City of Concord consider the following environmental issues for the
proposed project:
M. Sue Hyde, P.E.
Page Two
4. Prior to the issuance of the 401 Water Quality Certification, the City of Concord is respectfully reminded that they
will need to demonstrate the avoidance and minimization of impacts to wetlands (and streams) to the maximum
extent practical. In accordance with the Environmental Management Commission's Rules {15A NCAC
2H.0506(h)), mitigation will be required for impacts of greater than 1 acre to wetlands. In the event that mitigation is
required, the mitigation plan should be designed to replace appropriate lost functions and values. The NC
Ecosystem Enhancement Program may be available for use as wetland mitigation.
5. In accordance with the Environmental Management Commission's Rules (15A NCAC 2H.0506(h)), mitigation will be
required for impacts of greater than 150 linear feet to any single perennial stream. In the event that mitigation is
required, the mitigation plan should be designed to replace appropriate lost functions and values. The NC
Ecosystem Enhancement Program may be available for use as stream mitigation.
6. DWQ is very concerned with sediment and erosion impacts that could result from this project. The City of Concord
should address these concerns by describing the potential impacts that may occur to the aquatic environments and
any mitigating factors that would reduce the impacts.
7. Whenever possible, the DWQ prefers spanning structures. Spanning structures usually do not require work within
the stream or grubbing of the streambanks and do not require stream channel realignment. The horizontal and
vertical clearances provided by bridges allow for human and wildlife passage beneath the structure, do not block
fish passage and do not block navigation by canoeists and boaters.
8. Bridge deck drains should not discharge directly into the stream. Stormwater should be directed across the bridge
and pre-treated through site-appropriate means (grassed swales, pre-formed scour holes, vegetated buffers, etc.)
before entering the stream. Please refer to the most current version of NC DWQ Stormwater Best Management
Practices.
9. If concrete is used during construction, a dry work area should be maintained to prevent direct contact between
curing concrete and stream water. Water that inadvertently contacts uncured concrete should not be discharged to
surface waters due to the potential for elevated pH and possible aquatic life and fish kills.
10. If temporary access roads or detours are constructed, the site shall be graded to its preconstruction contours and
elevations. Disturbed areas should be seeded or mulched to stabilize the soil and appropriate native woody
species should be planted.
11. When using temporary structures, the area should be cleared but not grubbed. Clearing the area with chain saws,
mowers, bush-hogs, or other mechanized equipment and leaving the stumps and root mat intact allows the area to
re-vegetate naturally and minimizes soil disturbance.
12. Placement of culverts and other structures in waters, streams, and wetlands shall be below the elevation of the
streambed by one foot for all culverts with a diameter greater than 48 inches, and 20 percent of the culvert diameter
for culverts having a diameter less than 48 inches, to allow low flow passage of water and aquatic life. Design and
placement of culverts and other structures including temporary erosion control measures shall not be conducted in
a manner that may result in dis-equilibrium of wetlands or streambeds or banks, adjacent to or upstream and down
stream of the above structures. The applicant is required to provide evidence that the equilibrium is being
maintained if requested in writing by DWQ. If this condition is unable to be met due to bedrock or other limiting
features encountered during construction, please contact the NC DWQ for guidance on how to proceed and to
determine whether or not a permit modification will be required.
13. If multiple pipes or barrels are required, they should be designed to mimic natural stream cross section as closely
as possible including pipes or barrels at flood plain elevation and/or sills where appropriate. Widening the stream
channel should be avoided. Stream channel widening at the inlet or outlet end of structures typically decreases
water velocity causing sediment deposition that requires increased maintenance and disrupts aquatic life passage.
14. If foundation test borings are necessary; it should be noted in the document. Geotechnical work is approved under
General 401 Certification Number 3494/Nationwide Permit No. 6 for Survey Activities.
M. Sue Hyde, P.E.
Page Three
15. Sediment and erosion control measures sufficient to protect water resources must be implemented and maintained
in accordance with the most recent version of North Carolina Sediment and Erosion Control Planning and Design
Manual and the most recent version of NCS000250.
16. All work in or adjacent to stream waters should be conducted in a dry work area unless otherwise approved by NC
DWQ. Approved BMP measures from the most current version of NCDOT Construction and Maintenance Activities
manual such as sandbags, rock berms, cofferdams and other diversion structures should be used to prevent
excavation in flowing water.
17. Sediment and erosion control measures should not be placed in wetlands and streams.
18. Borrow/waste areas should avoid wetlands to the maximum extent practical. Impacts to wetlands in borrow/waste
areas could precipitate compensatory mitigation.
19. Heavy equipment should be operated from the bank rather than in stream channels in order to minimize
sedimentation and reduce the likelihood of introducing other pollutants into streams. This equipment should be
inspected daily and maintained to prevent contamination of surface waters from leaking fuels, lubricants, hydraulic
fluids, or other toxic materials.
20. In most cases, the DWQ prefers the replacement of the existing structure at the same location with road closure. If
road closure is not feasible, a temporary detour should be designed and located to avoid wetland impacts, minimize
the need for clearing and to avoid destabilizing stream banks. If the structure will be on a new alignment, the old
structure should be removed and the approach fills removed from the 100-year floodplain. Approach fills should be
removed and restored to the natural ground elevation. The area should be stabilized with grass and planted with
native tree species. Tall fescue should not be used in riparian areas.
21. Riprap should not be placed in the active thalweg channel or placed in the streambed in a manner that precludes
aquatic life passage. Bioengineering boulders or structures should be properly designed, sized and installed.
Thank you for requesting our input at this time. The City of Concord is reminded that issuance of a 401 Water Quality
Certification requires that appropriate measures be instituted to ensure that water quality standards are met and
designated uses are not degraded or lost. If you have any questions or require additional information, please contact
Polly Lespinasse at [phone].
Cc: Liz Hair, USACE Asheville Regional Office (electronic copy)
Chris Militscher, EPA (electronic copy)
Marella Buncick, US Fish and Wildlife Service (electronic copy)
Marla Chambers, NC Wildlife Resources Commission (electronic copy)
Sonia Gregory, DWQ Transportation Permitting Unit (electronic copy)
File Copy ,