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HomeMy WebLinkAbout20100107 Ver 1_Complete File_20100726t f ? ? ? l Level I Assessment Directions for use: The observer is to survey a minimum of 500 feet of stream, preferably in an upstream direction starting above the bridge pool and the road right-of-way. The segment which is assessed should represent average stream conditions. To perform a proper habitat evaluation the observer needs to get into the stream. To complete the form, select the description which best fits the observed habitats and then circle the score. If the observed habitat falls in between two descriptions, select an intermediate score. A final habitat score is determined by adding the results from the different metrics. Stream_Long Creek Location/road: SR 1117 (Road Name_Moose Branch Rd.?County_Graham Date June 13, 2003 8 Digit HUC Basin Little Tennessee Class C-trout Stream Order 4 Catchment Size (mi) Observer(s) Latitude Longitude Ecoregion: ? P ? Slate Belt ? Triassic ? Sand Hills Agency Identification/Tracking Information (TIP#, Action#, etc.) B- 4122 Physical Characterization: Visible land use refers to immediate area that you can see from sampling location. Visible Land Use: _50_0/oForest _30_0/oResidential %Active Pasture _5 % Active Crops %Fallow Fields 10 % Commercial 5 %Industrial %Other - Describe: Observed driving through watershed or from maps, aerial photos, etc. Watershed land use : X?Forest X ?Agriculture X?Urban ? Animal operations upstream ? Commercial * The following three (3) parameters are all estimated: Width: (ft) Current wet width - Stream_36' Channel (at top of bank) ? Width variable 2"-16" Stream Depth: (ft) Riffles - Avg Max Pools - Avg Max. Bank Height (from deepest part of channel (in riffle or run) to top of bank): (ft) Bank Angle: ° or ? NA (Vertical is 90°, horizontal is 0°. Angles > 90° indicate slope is towards mid-channel, < 90° indicate slope is away from channel. NA if bank is too low for bank angle to matter.) General Observations ?Channelized Ditch ?Dam upstream ?Other hydrologic alterations ?Manmade Stabilization ?Rip-rap, cement, gabions ?Sediment/grade-control structure X?Berm/levee ?Deeply incised ?Both banks undercut at bend ?Channel filled in with sediment ?Steep,straight banks ?Bar development ?Buried structures ?Exposed bedrock ?Recent overbank deposits ?Heavy filamentous algae growth ?Green tinge ?Sewage smell ?Excessive periphyton growth ?Livestock with access to stream ?Evidence of human use (trash, foot paths, etc.) Flow conditions : ?High X?Normal ?Low Turbidity: ?Clear X? Slightly Turbid ?Turbid ?Tannic ?Milky ?Colored (from dyes) Current Weather Conditions:_Cloudy Recent Weather Conditions Photos: ?N ?Y X ? Digital ?35mm Remarks:-Berm on right ride downstream. Wooden bridge, rails and wingwalls. Utility lines across stream just upstream of bridge Upstream and downstream banks are vegetated with overhanging trees. Stream substrate is cobble and boulders. J :.... Rr` s _. 4 ,sue $ { s,C?x ° { s $ < 13. d Sf j,' t T g ? f? ' i a ! / L• d?L?lg1N ?/ir2A11 A IL EXECUTIVE SUMMARY Replacement of Bridge Number 81 on SR 1117 over Long g Graham County, North Carolina 6` -i TIP No. B-4122'?? State Project No.8.2930901 Federal Aid Project No. BRZ-1117(8) ?? ?// February 2003 Proposed replacement of Bridge No. 81 on State Route (SR) 1117 (Moose Branch Road) over Long Creek in Graham County, North Carolina; TIP No. B-4122. INTRODUCTION This report documents the initial assessment of natural resources on this proposed bridge replacement project site. This information will assist in the development of project alternatives and the preliminary designs. The project involves the replacement of Bridge No. 81 on State Route (SR) 1117 (Moose Branch Road) over Long Creek in Graham County, North Carolina. Bridge No. 81 is a two lane steel and timber bridge located approximately 1,050 feet (320 meters) west of Main Street (SR 1106) in the Town of Robbinsville. The bridge is approximately 44 feet (13.5 meters) long with a clear deck width of 25 feet (7.6 meters). No project alternatives have been identified. If a temporary detour on existing roads is used, no temporary crossing of Long Creek near the construction site would be necessary. A temporary detour using the western end of Moose Branch Road (SR 1117), U.S. 129, and SR 1 156 may be feasible, but these routes should be assessed to ensure that they are suitable to handle the additional traffic volumes. The project is located in the Blue Ridge Physiographic Province of North Carolina. Long Creek is a blue-line perennial mountain creek approximately 28 feet (8.5 meters) wide and 1 to 2 feet (0.3 to 0.6 meter) deep, and generally flows in a north to northwest direction at the bridge site. The channel is incised at this crossing location. The creek bed is typical of lower elevation mountain creeks consisting of sand to medium round boulders. In this municipal location, the creek bank has been hardened in places with rip-rap. No hydric soil occurs within the project study area. , A An intermittent tributary to Long Creek is also located in the study area. Mauney Branch flows from the west through the residential area north of Moose Branch Road (SR 1117). Mauney Branch is 1 to 3 feet (0.3 to 0.9 meter) wide. This branch splits in the study area as it flows toward Long Creek. The northern channel drains to the northeast into Long Creek, north of the study area. The southern channel joins the roadside ditch along the north side of Moose Branch Road before it enters Long Creek. West of the study area along Moose Branch Road, Mauney Branch is flow regulated, resulting in an area of backed up waters and a fenced off "trout pond" at a private residence. Impacts resulting from in-place bridge replacements are generally limited to narrow strips at or adjacent to the existing bridge structure and roadway approach segments. These areas are already developed as a Commercial District or Rural Residential. The Commercial District has a higher percent of impervious surface as a source for non-point source drainage to the creek than does the Rural Residential/Maintained/Disturbed Land use type. The road side edge of a small agricultural field near Moose Branch Road and the bridge site may also be affected. The project vicinity is primarily rural residential, municipality, and forest lands. Surrounding land uses include government, commercial, agricultural, residential, and forest lands. East of the bridge, the land use identified as Commercial District contains a school, community college campus, and emergency services building. PHYSICAL CHARACTERISTICS Water Resources The project study area is located within sub-basin 04-04-04 of the Little Tennessee River Basin and is part of the USGS hydrologic unit for the Lower Little Tennessee (HUC No. 06010204). The Little Tennessee River Basin is not currently subject to state riparian buffer rules. Long Creek (SIN 2-190-4-(5)) is a tributary of the Cheoah River, upstream of Santeetlah Lake. The Cheoah River then flows northwest into the Little Tennessee River. Mauney Branch, identified by SIN 2-190-4-9, is mapped as an intermittent blue-line creek. Long Creek has been assigned a Best Usage Classification of C Tr and is not listed on the Section 303(d) Waters list as an impaired waterway. No Outstanding Resource Waters occur within 3.0 miles (4.8 kilometers) upstream or downstream of the project study area. High Quality Waters (HOW) and Water Supply Waters (WS-1) occur just over 3.0 miles (4.8 kilometers) upstream of the project site. The Town of Robbinsville's water supply, located on Rock Creek (SIN 2-190-4-4-(1)), is approximately 0.1 mile (0.2 kilometer) upstream of its confluence with Long Creek. Long Creek is not designated as a North Carolina Natural and Scenic River, or as a National Wild and Scenic River. 2 r A An intermittent tributary to Long Creek is also located in the study area. Mauney Branch flows from the west through the residential area north of Moose Branch Road (SR 1117). Mauney Branch is 1 to 3 feet (0.3 to 0.9 meter) wide. This branch splits in the study area as it flows toward Long Creek. The northern channel drains to the northeast into Long Creek, north of the study area. The southern channel joins the roadside ditch along the north side of Moose Branch Road before it enters Long Creek. West of the study area along Moose Branch Road, Mauney Branch is flow regulated, resulting in an area of backed up waters and a fenced off "trout pond" at a private residence. Impacts resulting from in-place bridge replacements are generally limited to narrow strips at or adjacent to the existing bridge structure and roadway approach segments. These areas are already developed as a Commercial District or Rural Residential. The Commercial District has a higher percent of impervious surface as a source for non-point source drainage to the creek than does the Rural Residential/Maintained/Disturbed Land use type. The road side edge of a small agricultural field near Moose Branch Road and the bridge site may also be affected. The project vicinity is primarily rural residential, municipality, and forest lands. Surrounding land uses include government, commercial, agricultural, residential, and forest lands. East of the bridge, the land use identified as Commercial District contains a school, community college campus, and emergency services building. PHYSICAL CHARACTERISTICS Water Resources The project study area is located within sub-basin 04-04-04 of the Little Tennessee River Basin and is part of the USGS hydrologic unit for the Lower Little Tennessee (HUC No. 06010204). The Little Tennessee River Basin is not currently subject to state riparian buffer rules. Long Creek (SIN 2-190-4-(5)) is a tributary of the Cheoah River, upstream of Santeetlah Lake. The Cheoah River then flows northwest into the Little Tennessee River. Mauney Branch, identified by SIN 2-190-4-9, is mapped as an intermittent blue-line creek. Long Creek has been assigned a Best Usage Classification of;C;, Tr and is not listed on the Section 303(d) Waters list as an impaired waterway. No Outstanding Resource Waters occur within 3.0 miles (4.8 kilometers) upstream or downstream of the project study area. High Quality Waters (HQW) and Water Supply Waters (WS-1) occur just over 3.0 miles (4.8 kilometers) upstream of the project site. The Town of Robbinsville's water supply, located on Rock Creek (SIN 2-190-4-4-(1)), is approximately 0.1 mile (0.2 kilometer) upstream of its confluence with Long Creek. Long Creek is not designated as a North Carolina Natural and Scenic River, or as a National Wild and Scenic River. 2 Biotic Resources No natural plant communities occur within the project study area. Four community/land use types resulting from human activities have been classified. These community/land uses total approximately 28.4 acres (11.5 hectares) within the study area. A summary of the coverage of each plant community within the project study area is presented in Table 1. Project alternatives have not been developed that will allow estimation of project impacts. These estimates will come as part of the preliminary design process. Table 1. Plant Communities and Land Uses occurring within the Project Study Area for Bridge No. 81 (TIP B-4122) Plant Community/Land Use Study Area Percent of Project Study (acres)/(hectares) Area White Pine Plantation/Mixed 2.0/0.8 7% Hardwoods Agricultural Lands 1.4/0.6 5% Commercial District Lands 11.0/4.4 39% Rural Residential/ 14.0/5.7 49% Maintained/Disturbed Lands Totals: 28.4/11.5 100% JURISDICTIONAL TOPICS Surface Waters and Wetlands National Wetland Inventory (NWI) mapping for this segment of Long Creek does not identify wetlands adjacent to the creek within the study area. The field assessment verified the NWI mapping in the project study area showing no wetlands. On this project site, "Waters of the United States" consist entirely of the Long Creek and Mauney Branch channels. Both creeks are palustrine, scrub-shrub, broad-leaved deciduous (PSS1). Mauney Branch has some segments that are ditched or have emergent vegetation and flows east. Long Creek has a Rosgen Stream Type Classification of "F" for the stream segment in the project area. The replacement of Bridge No. 81 can be classified as a Case 2 by the Best Management Practices (BMPs) for Bridge Demolition and Removal (NCDOT 1999). A moratorium on in water work from October through April, or later for rainbow trout, would be required for any Section 404 permit issued. Anadromous fish species do not occur here and will not be affected. 3 Permits If minor impacts occur to Long Creek and Mauney Branch, a Section 404 permit from the USACE and Section 401 certification will be required from the state prior to demolition and construction if fill is placed into "Waters of the United States." It is anticipated that a Nationwide Permit (NWP) No. 23 [33 CFR 330.5(a)(23)] could be required. Nationwide Permit No. 23 is for projects expected to have minimal impact. In the event that NWP No. 23 does not apply, minor impacts attributed to bridging and associated approach improvements are expected to qualify under a Regional General Bridge Permit designated for NCDOT bridges (Permit No. 031) issued by the Wilmington USACE District (USACOE- WD 1998). Notification to the Wilmington USACE office is required if this general permit is to be utilized. Nationwide Permit No. 33 may be required if temporary construction including cofferdams, access, and dewatering are required for this project. The USACE will determine final permit requirements. Protected Species Species with the federal classification of Endangered (E) or Threatened (T), or Officially Proposed (P) for such listing are protected under the Endangered Species Act (ESA) of 1973, as amended (16 U.S.C. 1531 et seq.). The federally protected species listed for Graham County (USFWS list dated January 2003) are shown in Table 2. The Appalachian elktoe (A/asmidonta raveneiiana) has been reported as an historic occurrence by the North Carolina Natural Heritage Program (NHP) in the area of the Robbinsville, NC, 7.5-minute USGS Quad Sheet. An historic occurrence means that the reported occurrence is older than 20 years. The other five species are listed as current (within the last 20 years). Table 2. Federally Protected Species Listed for Graham County, NC. Common Name Scientific Name Federal Status Biological Conclusion Carolina Northern Flying Squirrel G/aucomys sabrinus co%ratus E No Effect Indiana Bat Myotis sodaiis E No Effect Bog Turtle C/emmys muh/enbergii T(S/A) N/A Appalachian Elktoe Aiasmidonta raveneiiana E Unresolved - May Affect Rock Gnome Lichen Gymnoderma iineare E No Effect Virginia Spiraea Spiraea virginiana T No Effect E- Endangered, T- Threatened, T(S/A)- Threatened in the southern U.S. due to similarity in appearance to the northern population. N/A Biological Conclusion not required. 4 Carolina Northern Flying Squirrel Biological Conclusion: No Effect There is no suitable habitat for the Carolina northern flying squirrel within the project study area. Elevations in the project study area range from greater than 1,960 to about 2,040 feet (600 to 620 meters) above mean sea level and no spruce-fir forests are present. No know recent occurrence of Carolina northern flying squirrel has been reported in the immediate Long Creek drainage. Indiana Bat Biological Conclusion: No Effect No critical hibernation, roosting, foraging or maternity habitat for Indiana bat is present within the project study area. No known occurrence of Indiana bat has been reported in the immediate Long Creek drainage. However, critical habitat (hibernacula) for Indiana bat has been reported to occur in the Cheoah Ranger District of the Nantahala National Forest in Graham County. Bog Turtle Biological Conclusion: N/A There is no suitable habitat for the bog turtle within the project study area. No known recent occurrence of bog turtle has been reported in the immediate Long Creek drainage. Bog turtle is listed in the southern part of its range due to its similarity of appearance to the northern population of bog turtle that is federally protected. T S/A species are not subject to Section 7 consultation and a biological conclusion for this species is not required. Appalachian Elktoe Biological Conclusion: Unresolved - May Effect No in-water survey was specifically conducted for Appalachian elktoe in the project study area or vicinity, specifically in Long Creek (SIN 2-190-4-(5)) and Mauney Branch (SIN 2- 190-4-9). As these creeks occur in the Little Tennessee watershed, and since Appalachian elktoe is reported to occur in Tulula Creek (in the same drainage as Long Creek), there is a strong possibility that it may also occur in Long Creek and Mauney Branch. A mussel survey by an appropriately trained biologist in mussel surveys should be conducted. Rock Gnome Lichen Biological Conclusion: No Effect There is no suitable habitat for the rock gnome lichen within the project study area. Elevations in the project study are range from greater than 1,960 to about 2,040 feet (600 to 620 meters) above mean sea level, much less than that required for rock gnome lichen. No know recent occurrence of rock gnome lichen has been reported in the immediate Long Creek drainage. Virginia Spiraea Biological Conclusion: No Effect There is no suitable habitat for the Virginia spiraea within the project study area. No know recent occurrence of Virginia spiraea has been reported in the immediate Long Creek drainage. 5 CONCLUSIONS The project is located in the Little Tennessee River Basin and is not currently subject to vegetated riparian buffer requirements by the state and there are no jurisdictional wetlands in the project area. Long Creek and Mauney Branch are the two jurisdictional waters in the project area. After the project alternatives are developed, the impacts to these streams will be assessed. If impacts to jurisdictional waters occur, a Section 404 NWP Nos. 23, 33, or Regional General Bridge Permit No. 031 along with their corresponding Section 401 Water Quality Certifications would be required. A mussel survey is recommended to resolve the biological conclusion for the Appalachian elktoe. The replacement of Bridge No. 81 will not affect any other listed federally protected species in Graham County. Aquatic wildlife may be temporarily displaced during construction of this bridge replacement project. A moratorium on in-water work would be required as a condition of any Section 404 permit issued. This moratorium would be from October through April. The moratorium for rainbow trout (Oncorhynchus mykiss) would be slightly later. 6 •, i'L6 ,1( V Nf 1139 ns 1196 1106 ?// M17t Lll? / ' 2C + \ . 12c 101` \ -_ „? a 1 ? r 1121 ll \ Ims Mate. \ 12 1116 \? •`` i. 1112 P93-- ; -M t 1170 is 1 22 ._1 1214 122 0134 HORTFI C+1ya` NORTH CAROLINA DEPARTMENT OF g TRANSPORTATION DIVISION OF HIGHWAYS v PROJECT DEVELOPMENT & 9'?iF1rOF ?I ENVIRONMENTAL ANALYSIS BRANCH GRAHAM CouNiT REPLACE BRIDGE NO. 81 ON SR 1117 OVER LONG CREEK B-4122 Figure 1 .,? C132 1219}®.. 1 . ,C. .09 / ® ?? •? TWO to d, 12M • 8 1O M 1 S 1 J .136 ) i-- y tv, 1210.1 1270 1 . _a? • ? , / 7 1 t S 118 `? _ _... ' i 1280 r y Ian •.? M-- v " (??+`i) t ,i ; Sa cYt?it ? ???} . ? t\. Ch ? r ' Basi LOT 04 Elev 1940 f Hkg?i1. J * ?' 41 Gap ?: .- ! / ? v ?<w - ? . ? ti •? ? ._..- :. ? ?. 1256. " `?` 1.?? 1214.. v 10 'Mite T ee Gad -_,\ k6 r y `\\\ ?? \ J LHT 967 \ ROBBIN Vj?lauhey SVI Gap ' r ??7? r.et+s LhF..xa? 2015 i ?- tti' ? l.? ?- ?,r 17 C MM 4L LHT- "N 0 Q. 1 j 4 Sri a> t ,* j 9\ , l ?? t7FJ(?21 1( C? ? - ? j ? "? i s¢ ? A ? . ham` 3• . WA 7 4 V LN? 6 3 1 C ?. 111 o bffd p? + . j"= _ mX -7 2072 toah Ch -_4 ` J A Rr L (' anti 411 I f --s if ?1` ` , ( ?T if ?JJJ a o t Name: ROBBINSVILLE Location: 035° 19'30.6" N 083° 48'42.3" W Date: 1/14/2002 Caption: B-4122 Scale: 1 inch equals 2000 feet Figure 2 ----------- Copyright ap ec Inc. II1 a on b?! y O N 00 N W III O O O O N O O D Z n C Z \ D Z D C C.n rn FTl Z -o rn O ?r 0 b OD O s m° 0 2D0 C) w ZDi `J ?DA mz ? Z A NN. m m m 0 0 ? y O O ~ 2 r O p N y r n C 70 rfl Cam.) iI L- l A ® North Carolina Wildlife Resources Commission Charles R. Fullwood, Executive Director TO: William T. Goodwin, Jr., PE, Unit Head Bridge Replacement Planning Unit, NCDOT FROM: Marla Chambers, Highway Projects Coordinator Habitat Conservation Program, NCWRC DATE: July 18, 2003 SUBJECT: Review of Natural Systems Technical Reports for bridge replacement projects scheduled for construction in CFY 2006. RED LIGHT. Bridge No. 81 on SR 1117 (Moose Branch Road) over Long Creek, Graham County. TIP No. B-4122. North Carolina Department of Transportation (NCDOT) has requested comments from the North Carolina Wildlife Resources Commission (NCWRC) regarding impacts to fish and wildlife resources resulting from the subject projects. Staff biologists have reviewed the Executive Summaries for the Natural Systems Technical Reports and have the following preliminary comments. These comments are provided in accordance with the provisions of the National Environmental Policy Act (42 U.S.C. 4332(2)(c)) and the Fish and Wildlife Coordination Act (48 Stat. 401, as amended; 16 U.S.C. 661-667d). Our standard recommendations for bridge replacement projects of this scope are as follows: We generally prefer 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. 2. Bridge deck drains should not discharge directly into the stream. 3. Live concrete should not be allowed to contact the water in or entering into the stream. 4. If possible, bridge supports (bents) should not be placed in the stream. Mailing Address: Division of Inland Fisheries • 1721 Mail Service Center • Raleigh, NC 27699-1721 Telephone: (919) 733-3633 ext. 281 0 Fax: (919) 715-7643 B-4122, Bridge No. 81 Long Creek, Graham Co. 2 July 18, 2003 5. 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 revegetate naturally and minimizes disturbed soil. 6. A clear bank (riprap free) area of at least 10 feet should remain on each side of the steam underneath the bridge. 7. In trout waters, the N.C. Wildlife Resources Commission reviews all U.S. Army Corps of Engineers nationwide and general `404' permits. We have the option of requesting additional measures to protect trout and trout habitat and we can recommend that the project require an individual `404' permit. In streams that contain threatened or endangered species, Mr. Hal Bain with the NCDOT - ONE should be notified. Special measures to protect these sensitive species may be required. NCDOT should also contact the U.S. Fish and Wildlife Service for information on requirements of the Endangered Species Act as it relates to the project. 9. In streams that are used by anadromous fish, the NCDOT official policy entitled "Stream Crossing Guidelines for Anadromous Fish Passage (May 12, 1997)" should be followed. 10. In areas with significant fisheries for sunfish, seasonal exclusions may also be recommended. 11. Sedimentation and erosion control measures sufficient to protect aquatic resources must be implemented prior to any ground disturbing activities. Structures should be maintained regularly, especially following rainfall events. 12. Temporary or permanent herbaceous vegetation should be planted on all bare soil within 15 days of ground disturbing activities to provide long-term erosion control. 13. 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. 14. 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. 15. Only clean, sediment-free rock should be used as temporary fill (causeways), and should be removed without excessive disturbance of the natural stream bottom when construction is completed. ti B-4122, Bridge No. 81 Long Creek, Graham Co. 3 July 18, 2003 16. During subsurface investigations, equipment should be inspected daily and maintained to prevent contamination of surface waters from leaking fuels, lubricants, hydraulic fluids, or other toxic materials. 17. If culvert installation is being considered, conduct subsurface investigations prior to structure design to determine design options and constraints and to ensure that wildlife passage issues are addressed. If corrugated metal pipe arches, reinforced concrete pipes, or concrete box culverts are used: 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 (similar to Lyonsfield design). These should be reconnected to floodplain benches as appropriate. This may be accomplished by utilizing sills on the upstream end to restrict or divert flow to the base flow barrel(s). Silled barrels should be filled with sediment so as not to cause noxious or mosquito breeding conditions. 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 must 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 B-4122, Bridge No. 81 Long Creek, Graham Co. 4 July 18, 2003 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. Project specific comments: 1. B-4122, Graham Co., Bridge No. 81 on SR 1117 (Moose Branch Road) over Long Creek. RED LIGHT. Long Creek is classified as C Tr and is Hatchery Supported DPMTW, containing both stocked and wild trout. Records indicate an occurrence of the Appalachian Elktoe, federal and state Endangered, in Tulula Creek within the project drainage. We request NCDOT coordinate the mussel surveys with Steve Fraley, NCWRC Western Aquatic Nongame Coordinator (828-627-8414). A moratorium prohibiting in-stream work and land disturbance within the 25-foot trout buffer is recommended from October 15 to April 15 to protect the egg and fry stages of trout. Sediment and erosion control measures should adhere to the design standards for sensitive watersheds. We recommend incorporating into the design an area where the public can pull off of the road for safer public access to the resource. We request that NCDOT routinely minimize adverse impacts to fish and wildlife resources in the vicinity of bridge replacements. The NCDOT should install and maintain sedimentation control measures throughout the life of the project and prevent wet concrete from contacting water in or entering into these streams. Replacement of bridges with spanning structures of some type, as opposed to pipe or box culverts, is recommended in most cases. Spanning structures allow wildlife passage along streambanks, reducing habitat fragmentation and vehicle related mortality at highway crossings. If you need further assistance or information on NCWRC concerns regarding bridge replacements, please contact me at (704) 485-2384. Thank you for the opportunity to review and comment on these projects. cc: Cynthia Van Der Wiele, DWQ Marella Buncick, USFWS Sarah McRae, NHP