20090374 Ver 1_Memorandum of Agreement_20050923

?{J
\o?oF w,arF9Q?
r
C Y
Michael F. Easley, Governor
???//???' /f??? William G. Ross Jr., Secretary
S CP n North'CmU?yIYQ
l 4? //)/75 (l JUJ Department of Environment and Natural Resources
Alan W. Klimek, P.E. Director
0ENR.
I A, Division of Water Quality
September 22, 2005

MEMORANDUM
TO: Gregory J. Thorpe, Ph.D. Director
Project Development and Environmental Analysis Branch, NCDOT
FROM: Sue Homewood, NC Division of Water Quality, Winston-Salem Regional Office
SUBJECT: Scoping Review of NCDOT's Proposed Bridge Replacement Projects:
B-4510, Forsyth County
B-3234, Rowan County
B-4627, Rowan County
B-4402, Alamance County
B-4498, Davidson County
B-4499, Davidson County
B-4622, Rockingham County
In reply to your correspondence dated September 5, 2005 in which you requested comments for the above referenced
projects, the NC Division of Water Quality offers the following comments:
1. Project-Specific Comments
B-4510, Bridge No. 368 on SR 2643 over I-40 Business, Forsyth County
Adjacent unnamed tributaries drain to Smith Creek and Abbotts Creek which are both WS-III Waters of the State.
DWQ has no specific comments regarding this project.
B-3234, Bridge No. 78 on SR 1949 over an unnamed tributary to Fourth Creek, Rowan County
Fourth Creek and its tributaries in this area are classified as C Waters of the State. The section of Fourth Creek that
the unnamed tributary drains to is on the DWQ 303(d) impaired waters list. DWQ requests that NCDOT utilize the
most stringent and protective erosion and sediment control practices available.
B-4627, Bridge No. 26 on SR 1003 over an Third Creek, Rowan County
Third Creek is a Class C Waters of the State. DWQ has no specific comments regarding this project.
B-4402, Bridge No. 7 on SR 1504 over Tickle Creek, Alamance County
Tickle Creek is a Class C, Nutrient Sensitive Waters of the State. DWQ has no specific comments regarding this
project.
North Carolina Division of Water Quality 585 Waughtoum Street
. Internet h2o.enr.state.nc.us Winston-Salem, NC 27107
No ?hCarolina
Naturally
Phone [phone] Customer Service
FAX [phone]
An Equal Opportunity/Affirmative Action Employer- 50% Recycled/10% Post Consumer Paper
Gregory J. Thorpe, Ph.D., Director
September 22, 2005
Page 2
B-4498, Bridge No. 199 on SR 1243 over Abbott's Creek, Davidson County
Abbott's Creek at this location is classified as C Waters of the State. This section of Abbott's Creek is on the DWQ
303(d) impaired waters list. DWQ requests that NCDOT utilize the most stringent and protective erosion and
sediment control practices available.
B-4499, Bridge No. 158 on SR 1792 over US 29/1-85 Business, Davidson County
Adjacent unnamed tributaries in this project area drain to Hunt's Fork Creek is classified as a C Waters of the State.
This section of Hunt's Fork Creek is on the DWQ 303(d) impaired waters list. DWQ requests that NCDOT utilize
the most stringent and protective erosion and sediment control practices available.
B-4622, Bridge No. 54 on NC 65 over Rock House Creek, Rockingham County
Rock House Creek is classified as a WS-IV Waters of the State. There is Natural Heritage Area in the vicinity of
this project. NCDOT should conduct all necessary investigations to address possible impacts to the Natural
Heritage Area.
H. General Comments Regarding Bridge Replacement Projects
1. If corrugated metal pipe arches, reinforced concrete pipes, or concrete box culverts are used to replace the
bridge, then DWQ recommends the use of Nationwide Permit No. 14 rather than Nationwide Permit 23.
2. If the old bridge is removed, no discharge of bridge material into surface waters is preferred. Strict adherence
the Corps of Engineers guidelines for bridge demolition will be a condition of the 401 Water Quality
Certification.
3. DWQ prefers spanning structures. Spanning structures usually do not require work within the stream and do
not require stream channel realignment. The horizontal and vertical clearances provided by bridges allows for
human and wildlife passage beneath the structure, does not block fish passage, and does not block navigation by
canoeists and boaters.
4. 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 NCDOT Best Management Practices for the Protection
of Surface Waters
5. Live concrete should not be allowed to contact the water in or entering into the stream. Concrete is mostly
made up of lime (calcium carbonate) and when in a dry or wet state (not hardened) calcium carbonate is very
soluble in water and has a pH of approximately 12. In an unhardened state concrete or cement will change the
pH of fresh water to very basic and will cause fish and other macroinvertebrate kills.
6. If possible, bridge supports (bents) should not be placed in the stream.
7. If temporary access roads or detours are constructed, they should be removed back to original ground elevations
immediately upon the completion of the project. Disturbed areas should be seeded or mulched to stabilize the
soil and native tree species should be planted with a spacing of not more than 10'x10'. If possible, 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 disturbed soil.

8. A clear bank (rip rap-free) area of at least 10 feet should remain on each side of the stream underneath the
bridge.
1
Ile
pS Gregory J. Thorpe, Ph.D., Director
September 22, 2005
Page 3
I .
9. Sedimentation and erosion control measures sufficient to protect water resources must be implemented prior to
any ground disturbing activities. Structures should be maintained regularly, especially following rainfall .
events.
10. Bare soil should be stabilized through vegetation or other means as quickly as feasible to prevent sedimentation
of water resources.
11. All work in or adjacent to stream waters should be conducted in a dry work area. Sandbags, rock berms,
cofferdams, or other diversion structures should be used where possible to prevent excavation in flowing water.
12. 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.
III. General Comments if Replacing the Bridge with a Culvert
1. The culvert must be designed to allow for aquatic life and fish passage. Generally, the culvert or pipe invert
should be buried at least 1 foot below the natural streambed (measured from the natural thalweg depth). If
multiple barrels are required, barrels other than the base flow barrel(s) should be placed on or near stream
bankfull or floodplain bench elevation. These should be reconnected to floodplain benches as appropriate.
Sufficient water depth should be provided in the base flow barrel during low flows to accommodate fish
movement. If culverts are longer than 40-50 linear feet, alternating or notched baffles should be installed in a
manner that mimics existing stream pattern. This should enhance aquatic life passage: 1) by depositing
sediments in the barrel, 2) by maintaining channel depth and flow regimes, and 3) by providing resting places
for fish and other aquatic organisms. In essence, the base flow barrel(s) should provide a continuum of water
depth and channel width without substantial modifications of velocity.
2. If multiple pipes or cells are used, at least one pipe or box should be designed to remain dry during normal
flows to allow for wildlife passage.
3. Culverts or pipes should be situated along the existing channel alignment whenever possible to avoid channel
realignment. 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.
4. 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 professionally designed, sized, and
installed.
In most cases, we prefer 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 down 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. If the area that is reclaimed was previously wetlands, NCDOT should restore the area to wetlands.
If successful, the site may be used as wetland mitigation for the subject project or other projects in the watershed.
Gregory J. Thorpe, Ph.D., Director
September 22, 2005
Page 4
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 Sue Homewood at 336-771-
4600 extension 287 or [e-mail].
cc: Vincent J. Rhea, PDEA, NCDOT
Todd Tugwell, USACE Raleigh Field Office
John Thomas, USACE Raleigh Field Office
Marla Chambers, NCWRC
Travis Wilson, NCWRC
Gary Jordan, USFWS
Marella Buncick, USFWS
DWQ Wetlands Transportation Unit
DWQ Winston-Salem Regional Office File Copy