HomeMy WebLinkAbout20210922 Ver 1_Pre-Filing Meeting Information_20210504
North Carolina Department of Environmental Quality Division of Water Resources
512 North Salisbury Street 1617 Mail Service Center Raleigh, North Carolina 27699-1617
919.707.9000
ROY COOPER
Governor
MICHAEL S. REGAN
Secretary
LINDA CULPEPPER
Director
April 4, 2019
MEMORANDUM ____
TO: John Thomas, Assistant Environmental Officer, NCDOT Division 4
FROM: Rob Ridings, NC Division of Water Resources, Transportation 401 & Buffer Permitting Unit
SUBJECT: Scoping Review of NCDOT’s Proposed Division 4 Bridge Replacement Projects
In reply to your correspondence received April 3, 2019 in which you requested comments for six Division 4 Bridge
projects, the NC Division of Water Resources offers the following comments:
Project-Specific Comments
Bridge 78 over Ballahack Canal, Edgecombe County, Tar-Pamlico Basin: C, NSW; 303(d) listed.
1. Ballahack Canal is class C; NSW; 303(d) impaired waters of the State. The NCDWR is very concerned with
sediment and erosion impacts that could result from this project. The NCDWR recommends that the most
protective sediment and erosion control BMPs be implemented to reduce the risk of nutrient runoff to
Ballahack Canal. Post-construction stormwater BMPs should, to the MEP, be selected and designed to reduce
target POCs in the 303(d) list for the receiving waters.
Bridge 29 over Corn Creek, Edgecombe County, Tar-Pamlico Basin: C, NSW.
Bridge 215 over UT Little Buffalo Creek, Johnston County, Neuse Basin: C, NSW.
Bridge 124 over UT Black Creek, Wilson County, Neuse Basin: C, Sw, NSW.
Bridge 149 over Goss Swamp, Wilson County, Neuse Basin: C, Sw, NSW.
Bridge 158 over Turner Swamp, Wilson County, Neuse Basin: C, Sw, NSW.
2. These streams are class C; NSW waters of the State. NCDWR is very concerned with sediment and erosion
impacts that could result from this project. NCDWR recommends that highly protective sediment and
erosion control BMPs be implemented to reduce the risk of nutrient runoff to these streams and their
tributaries. Post-construction stormwater BMPs should, to the MEP, be selected and designed to reduce
nutrients.
North Carolina Department of Environmental Quality Division of Water Resources
512 North Salisbury Street 1617 Mail Service Center Raleigh, North Carolina 27699-1617
919.707.9000
Comments applying to all six projects
3. To meet the requirements of NCDOT’s NPDES permit NCS000250 , the road design plans shall provide
treatment of the stormwater runoff through BMPs as detailed in the most recent version of the North Carolina
Department of Transportation Stormwater Best Management Practices Toolbox manual. The BMPs should,
to the MEP, be selected and designed to reduce impacts of the target pollutants of concern (POCs) for the
receiving waters.
4. These projects are within the Neuse and Tar-Pamlico River Basins. Riparian buffer impacts shall be avoided
and minimized to the greatest extent possible pursuant to 15A NCAC 2B .0233 or 15A NCAC 2B.0259,
respectively.
General Comments Regarding Bridge Replacement Projects
5. Any anticipated dewatering or access structures necessary for construction of bridges should be addressed in
the CE. 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 due to bridge construction.
6. The NCDWR is very concerned with sediment and erosion impacts that could result from this project. NC
DOT 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.
7. If foundation test borings are necessary; it shall be noted in the document. Geotechnical work is approved
under General 401 Certification Number 3883/Nationwide Permit No. 6 for Survey Activities.
8. If a bridge is being replaced with a hydraulic conveyance other t han another bridge, the NCDWR believes the
use of a Nationwide Permit may be required. Please contact the US Army Corp of Engineers to determine the
required permit(s).
9. If the old bridge is removed, no discharge of bridge material into surface waters is a llowed 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.
10. Whenever possible, the NCDWR prefers spanning structures. Spanning structures usually do not require
work within the stream or grubbing of the stream banks 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.
11. Bridge deck drains shall not discharge directly into the stream. Stormwater shall 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 NCDWR Stormwater Best
Management Practices.
12. 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 inadvertent ly contacts uncured concrete shall not be discharged
to surface waters due to the potential for elevated pH and possible aquatic life and fish kills. Concrete shall be
handled in accordance with the NPDES Construction General Permit NCG010000.
13. Bridge supports (bents) shall not be placed in the stream when possible.
North Carolina Department of Environmental Quality Division of Water Resources
512 North Salisbury Street 1617 Mail Service Center Raleigh, North Carolina 27699-1617
919.707.9000
14. 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 stab ilize 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.
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 shall be conducted in a dry work area unless otherwise approved by
the NCDWR. 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.
17. 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.
18. In most cases, the NCDWR 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
19. 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 downstream of the above structures. The applicant is required to provide
evidence that the equilibrium is being maintained if requested in writing by the NCDWR. If this condition is
unable to be met due to bedrock or other limiting features encountered during construction, please contact the
NCDWR for guidance on how to proceed and to determine whether or not a permit modification will be
required.
20. 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 and/or sills where appropriate.
Widening the stream channel shall be avoided. Stream channel widening at the inlet or outlet e nd of
structures typically decreases water velocity causing sediment deposition that requires increased maintenance
and disrupts aquatic life passage.
21. Riprap shall not be placed in the active thalweg channel or placed in the streambed in a manner that pre cludes
aquatic life passage. Bioengineering boulders or structures shall be properly designed, sized and installed.
22. Any anticipated bank stabilization associated with culvert installations or extensions should be addressed in
the Categorical Exclusion (CE) 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.
North Carolina Department of Environmental Quality Division of Water Resources
512 North Salisbury Street 1617 Mail Service Center Raleigh, North Carolina 27699-1617
919.707.9000
Thank you for requesting our input at this time. The DOT 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
Rob Ridings at rob.ridings@ncdenr.gov or 919-707-3873.