20110060 Ver 1_Scoping Comments_20090326

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North Carolina Department of Environment and Natural Resource, ,-

Division of Water Quality S
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Beverly Eaves Perdue Coleen H. Sullins
Director
G Dee Freeman
`Secretary
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March 20, 2009

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MEMORANDUM
TO: Jimmy Goodnight, PE. NCDOT
Mark Hussey, NCDOT l r:
FROM: Michael R. Parker, NCDWQ, Asheville Regional Office4?v
SUBJECT: Seeping Review of NCDOT's Proposed Bridge Replacement Project: B- 4183 (Madison
County), Bridges 28 and 29 NCSR 1526
In reply to your correspondence dated February 10, 2009 (received February 13, 2009) in which you
requested comments for the above referenced project. The Division of Water Quality (DWQ) is
responsible for the issuance of the Section 401 Water Quality Certification for activities that impact
Waters of the U. S., including wetlands. Based on a review of the project document the following streams
will be impacted by the proposed culvert construction project:
Stream Name River Basin Stream
Classifications Stream Index
Number
Crooked Creek. French Broad WS-11-1-IQW 6-96-10-1
Middle Fork French Broad WS-1I-HQW 6-96-10-1-8
NCDWQ offers the following comments:
Project-Specific Comments
Crooked Creek and Middle Fork Little Ivy River and associated unnamed tributaries are classified
as WS-II-HQW waters of the State. I ligh Quality Waters of the State in the project study area.
This is one of the highest classifications for water quality. Pursuant to 15A NCAC 211 .1006 and
15A NCAC 213 .0224, NCDOT will be required to obtain a State Stormwater Penult prior to
construction except in North Carolina's twenty coastal counties. NCDOT shall use the Design
Standards in Sensitive Watersheds [15A NCAC 413.0124 (a)-(e) for sediment and erosion control
because of the High Quality Waters and Water Supply classifications.
Any anticipated bank stabilization associated with culvert installations or extensions should be
addressed in the (CL) document. It is understood that final designs are not determined at the time
the CE is developed. However, the CE should discuss the potential for bank stabilization necessary
due to culvert installation..
3. Any anticipated dewatering or access structures necessary for construction of bridges should be
addressed in the CF. It is understood that final designs are not determined at the time the CE is
developed. However, the CE should discuss the potential for dewatering and access measures
necessary cfuc to bridge construction.
SURFACE WATER PROTECTION SECTION- Asheville Regional Office one r
2090 US Highway 70. Swannanoa, North Carolina 28778b211 N Oft[] C aro [ llla
Phone: [phone] FAX: [phone] JVaturally
Customer Service, 1-877-623-6748
Internet. httpalh2o.enr.state.iic,usincwetlands/
An Equal Opportunity 1 Alffnalive Aclion Employer

4. All channel relocations will be constructed in a dry work area and stabilized before stream flows are
diverted. Channel relocations will be completed and stabilized, and must be approved on site by
D\ Q'staff,tprior to diverting water into the new channel. Whenever, possible channel relocations
shall be allowed to stabilize for an entire growing season. Vegetation used for bank stabilization
shall be limited to native woody species, and should include establishment of a 30 foot side wooded
and all adjacent 20 foot wide vegetated buffer on both sides of the relocated channel to maximum
extent practical. A transitional phase incorporating coir fiber and seedling establishment is
allowable. Also, riprap may be allowed if it is necessary to maintain the physical integrity of the
stream, but the applicant must provide written justification and any calculation used to determine
the extent of riprap coverage requested.
General Comments Regarding Bridge Replacement Projects
I. NCDWQ is very concerned with sediment and erosion impacts that could result from this project.
NCDOT shall address these concerns by describing the potential impacts that may occur to the
aquatic environments and any mitigating factors that would reduce the impacts.
I. 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.
2. If a bridge is being replaced with a hydraulic conveyance other than another bridge, NCDWQ
believes the use of a Nationwide Permit may be required. Please contact the US Army Corp of
Engineers to determine the required permit(s).
3. If the old bridge is removed, no discharge of bridge material into surface waters is allowed unless
otherwise authorized by the US ACOE. Strict adherence to the Corps of Engineers guidelines for
bridge demolition will be a condition of the 401 Water Quality Certification.
4. Whenever possible, NCDWQ 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 shall allow for human and
wildlife passage beneath the structure. Fish passage and navigation by canoeists and boaters shall
not be blocked. Bridge supports (bents) should not be placed in the stream when possible.
5. Stormwater shall be 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 Management Practices.
6. If concrete is used during construction, a dry work area shall be maintained to prevent direct contact
between curing concrete and stream water. Water that inau'verttentiy contacts uncured concrete shall
not be discharged to surface waters due to the potential for elevated pH and possible aquatic life and
fish kills.
7. 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.
8. 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.
All work in or adjacent to stream waters shall be conducted in a dry work area unless otherwise
approved by NCDWQ. 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 shall be used to prevent excavation in flowing water.
10. 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.
11. In 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
feSClle shall not be used in riparian areas.
General Comments if Replacing the Bridge with a Culvert
Placement of culverts and other structures in waters, streams, and wetlands shall be below the
elevation of the streantbed 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'culverls 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. If this condition 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.
If multiple pipes or barrels are required, they shall be designed to mimic natural stream cross section
as closely as possible including pipes or barrels at flood plain elevation, tloodplain 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 velocity causing
sediment deposition that requires increased maintenance and disrupts aquatic life passage.
Riprap shall not be placed in the active thalweg channel or placed in the streambed in a manner that
precludes aquatic life passage. Biocnginecring boulders or structures shall be properly designed,
sized and installed.

Thank you for requesting our input at this time. NCDOT 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 Mike Parker at 828-296-4500.
cc: David Baker, US Army Corps of Engineers, Asheville Field Office
Clarence Coleman, Federal Highway Administration
Elizabeth Lusk, NCDOT PEDA
J. .1. Swain Jr., PE, Division 13 Engineer
Roger Bryan, Division 13 Environmental Officer
Marla Chambers, NC Wildlife Resources Commission
Transportation Permitting Unit
Mike Parker, NCDWQ Asheville Regional Office
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