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.
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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
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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
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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
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® 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