HomeMy WebLinkAbout20151246_Scoping Comments_20110310Beverly Eaves Perdue
Governor
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NCDETdR
North Carolina Department of Environment and Naturai Resources
Division of Water Quality �
Coleen H. Sullins
Director
March 10, 2011
MEMORANDUM
TO: Gregory J. Thorpe, Ph.D., Director, NCDOT PDEA
FROM:
SUBJECT:
Rob Ridings, NCDWQ Transportation Permitting Unit��
Dee Freeman
Secretary
Scoping Review of NCDOT's Proposed Bridge Replacement Projects: B-5121 & B-53 U
in Wake County.
Reference your correspondence dated received February 25, 201 I in which you requested comments for
the referenced project. Preliminary analysis of the project reveals the potential for impacts to perennial
streams and riparian buffers in the project area. Streams in the project area include:
River Basin & Stream
Stream Name Subbasio Classifications Stream Iodex Number 303(d) Listing?
Pigeon House NEU 02 C; NSW 27-33-18 Yes.
Branch
Williamson Branch NEU 02 C; NSW 27-33-18-I No.
FuRher investigations at a higher resolution should be undertaken to verify the presence of other streams
and/or jurisdictional wetlands in the area. In the event that any jurisdictional areas are identified, the
Division of Water Quality requests that NCDOT (or the consultant(s) that requested the comments)
wnsider the following environmental issues for the proposed project:
Project-Specific Comments
Pigeon House Branch and Williamson Branch are class C, NSW waters ofthe state. Additionally,
Pigeon House Branch is listed as 303(d) impaired waters of the State. 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 Sensitia�e Watersheds to reduce the risk of nutrient runoff to these waters. NCDWQ
requests that road design plans provide treatment of the stortn water runoff through best
management practices as detailed in the most recent version of NCDWQ Stormwater Best
Management Practices.
2. This project is within the Neuse River Basin. Riparian buffer impacts shall be avoided and
minimized to the greatest extent possible pursuant to l5A NCAC 2B.0233.
TranspoAation Permilting Uni�
1650 Mail Service Center, Ralegh, NoM Camlina 27699-1650
Phone: 919A07-63011 FAX: 979A076494
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3. Any anticipated bank stabilization associated with culvert installations or extensions should be '
• addressed iq the Categorical Exclusion (CE) document and permit applicptions. lt is understood that
final designs are not detertnined at the time the CE is developed. However, the CE should discuss
the potential for bank stabilization necessary due to culvert installation.
4. Any anticipated dewatering or access structures necessary for construction of bridges should be
addressed in the CE and permit applications. It is understood that final designs are not detecmined at
the time the CE is developed. However, the CE should discuss the potential for dewatering and
access measures necessary due to bridge construction.
General Commenfs Regarding Bridge Replacement Projects
I. NCDWQ is very concemed with sediment and erosion impacts that could result from this project.
NCDOT shall address these concems by describing the potential impacts that may occur to the
aquatic environments and any mitigating factors that would reduce the impacts.
2. If foundation test borings are necessary; it shall be noted in the document. Geotechnical work is
approved under General 401 Certification Number 3687/Nationwide Permit No. 6 for Survey
Activities.
3. [f a bridge is being replaced with a hydraulic conveyance other than another bridge, NCDWQ
believes the use of a Nationwide Pertnit may be required. Please contact the US Army Corp of
Engineers to determine the required permit(s).
4. [f the old bridge is removed, no discharge of bridge material into surface waters is allowed unless
othenvise authorized by the US ACOE. Suict adherence to the Corps of Engineers guidelines for
bridge demolition will be a condition of the 401 Water Quality Certification.
5. Whenever possible, NCDWQ prefers spanning structures. Spanning sUvctures 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 shall allow for human and
wildlife passage beneath the structure. Fish passage and navigation by canceists and boaters shall
not be blocked. Bridge supports (bents) should not be placed in the stream when possible.
6. Bridge deck drains shall not discharge directly into the sVeam. Stortnwater shall be directed across
[he 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
NCDWQ's Stormwater Best Mcmagement Practrces.
7. [F concrete is used during construction, a dry work area shall be maintained to prevent direct contact
between curing concrete and stream water. Water that inadvertently contacts uncured concrete shall
not be discharged to surface waters due to the potential for elevated pH and possible aquatic life and
_ fish kills. _ - . _ . .
8. If temporary access roads or detours are constructed, the site shall be graded to its preconstruction
contours and elevations. Disturbed areas shall be seeded or mulched to stabilize the soil and
appropriate native woody species shall be planted. When using temporary structures the area shall ,
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.
9. 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.
10. All work in or adjacgnt to stream waters shall be conducted in a dry work area unless otherwise
approved by NCDWQ. Approved BMP measures from the most current version ofNCDOT
Construction and Maintenance Activities manual such as sandbags, rock berms, cofferdams and
other diversion structures shall be used to prevent excavation in flowing water.
11. Heavy equipment shall 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 shall be inspected daily and maintained to prevent contamination of surface waters from
leaking fuels, lubricants, hydraulic fluids, or other toxic materials.
12. [n most cases, the NCDWQ prefers the replacement of the existing structure at the same location
with road closure. If road closure is not feasible, a temporary detour shall 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 shall be removed and the approach fills
removed from the 100-year floodplain. Approach fills shall be removed and restored to the natural
ground elevation. The area shall be stabilized with grass and planted with native tree species. Tall
fescue shall not be used in riparian areas.
General Comments if Replacing the Bridge with a Culvert
Placement of culverts and other sVuctures 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 NCDWQ. [f this wndition is unable to be met due to bedrock
or other limiting features encountered during construction, please contact the NCDWQ for guidance
on how to proceed and to determine whether or not a permit modification will be required.
2. [f multiple pipes or barrels are required, they shall be designed to mimic natural stream cross section
as closely as possible including pipes or bazrels at Flood plain elevation, floodplain benches and/or
sills may be required where appropriate. Widening the stream channel shall be avoided. Stream
channel widening at the inlet or outlet end of structures typically decreases water vebcity causing
sediment deposition that requires increased maintenance and disrupts aquatic life passage.
3. Riprap shall not be placed in the active thalweg channel or placed in the streambed in a manner that
precludes aquatic life passage. Bicengineering boulders or structures shall be properly designed,
sized and installed.
Thank you for requegting our input at this time. NCD�T 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. [f you have any questions or require
additional infortnation, please contact Rob Ridings at 919-807-6403.
cc: Eric Alsmeyer, US Army Corps of Engineers, Raleigh Field Office
Chris Murcay, Division 5 Environmental Officer
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