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HomeMy WebLinkAboutRowan Long Range Transp Plansf OF W ATF9 Er, ?? / Michael F Easley, Governor Q William G Ross Jr, Secretary orth Carolina Department of Environment and Natural Resources V0'4V,0 Tp?R ?Uq?/ Coleen H Sullins, Director Y?j0 n' Division of Water Quality 70&August 12, 2008 MEMORANDUM To Phil Conrad, Cabarrus-Rowan MPO From Amy Euliss, NC Division of Water Quality, Winston-Salem Regional Office Subject Comments on 2035 Long Range Transportation Plan in Rowan County Reference your correspondence dated June 26, 2008 in which you requested comments for the referenced Long Range Transportation plan Preliminary analysis of the LRTP area reveals the potential for multiple impacts to multiple perennial streams and jurisdictional wetlands in the Yadkin River Basin Sensitive resources in the plan area include but are not limited to Water Supply Watersheds, including the Critical Area, proposed High Rock Lake Buffer, and High Quality and/or Outstanding Resource Waters Any roads being constructed on new location could have significant cumulative and secondary environmental impacts as a result of economic development along the new highway corridor These impacts can be considered when permitting the projects Further investigations at a higher resolution should be undertaken to verify the presence of other streams and/orj unsdictional wetlands in the area In the event that any jurisdictional areas are identified, the Division of Water Quality requests that NCDOT consider the following environmental issues for the proposed project General Project Comments. 1 The environmental document shall 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 2H 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 2 Environmental assessment alternatives shall consider design criteria that reduce the impacts to streams and wetlands from storm water runoff These alternatives shall include road 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 After the selection of the preferred alternative and prior to an issuance of the 401 Water Quality Certification, the NCDOT and or the Rowan-Cabarrus MPO 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 elan shall he Mailing Address Phone (919) 807-6300 Location one 1617 Mail Service Center Fax 807-6492 NorthCarohna (919) 512 N Salisbury St Naturally Raleigh, NC 27699-1617 Raleigh, NC 27604 Internet www ncwaterouality ore Customer Service 1-877-623-6748 An Equal Opportunity/Affirmative Action Employer - 50% Recycled/10% Post Consumer Paper designed to replace appropriate lost functions and values The NC Ecosystem Enhancement Program may be available for use as wetland mitigation 4 In accordance with the Environmental Management Commission's Rules 115A 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 shall be designed to replace appropriate lost functions and values The NC Ecosystem Enhancement Program may be available for use as stream mitigation 5 DWQ is very concerned with sediment and erosion impacts that could result from these 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 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 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 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 should 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 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 9 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 end of structures typically decreases water velocity causing sediment deposition that requires increased maintenance and disrupts aquatic life passage 10 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 11 All work in or adjacent to stream waters shall 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 12 Sediment and erosion control measures shall not be placed in wetlands and streams 13 Borrow/waste areas shall avoid wetlands to the maximum extent practical Impacts to wetlands in borrow/waste areas could precipitate compensatory mitigation 14 While the use of National Wetland Inventory (WI) maps, NC Coastal Region Evaluation of Wetland Significance (NC-CREWS) maps and soil survey maps are useful tools, their inherent inaccuracies require that qualified personnel perform onsite wetland delineations prior to permit approval 15 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 16 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 shall be removed and the approach fills removed from the 100-year floodplam Approach fills should 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 17 Riprap shall 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 While this is not a complete list of environmental impacts associated with the 2035 LRTP plan for Rowan County, it should give you an understanding of environmental resources in your area as they relate to water quality As individual projects develop, we will be happy to comment further Thank you for requesting our input at this time The Cabarrus-Rowan MPO 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 Amy Euliss at (336) 771-4959 cc DWQ 401/Wetlands Transportation Group File Copy