20081261 Ver 1_WRC Comments_20080826

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North Carolina V~ildlife Resources Commission ~
MEMORANDUM
TO: Amanda Jones, USACOE D ~~~0 V
Asheville Regulatory Field Office
AUG 2 6 2008
FROM: Ron Linville, Regional Coordinator
Habitat Conservation Program ~~ps ~p STTO~r~A~R s~~H
DATE: August 21, 2008
SUBJECT: Rolling Hills Development -Sherwood Estates, Cove Creek, Watauga County
The applicant proposes to install a culvert to provide site access. Biologists with the North
Carolina Wildlife Resources Commission are familiar with habitat values in the area. These
comments are provided in accordance with the provisions of the Fish and Wildlife Coordination
Act (48 Stat. 401, as amended; 16 U.S.C. 661-667d) and the North Carolina Environmental
Policy Act (G. S. 113A-1 through 113A-10; NCAC 25).
The project is to install a 60' x 6' x 12' arch pipe to develop an eight (8) lot subdivision. Wild
brown and rainbow trout are known for the area. The green floater, Lasmigorra subviridis (FSC,
NCE), occurs in the Watauga River from just above the Watauga River gorge to just downstream
of Valle Crucis. This is a very small, low density, and vulnerable population.
Based on our review of the submittal, we will not object to the project as proposed providing the
following conditions are implemented:
1. Care in the installation of an arch pipe should be taken to ensure that the stream is not
over widened and that natural stream dimensions are provided and maintained.
2. In stream work and land disturbance within the 25-foot wide buffer zone are
prohibited during the brown and brook trout spawning season of October 15 through
April 15 to protect the egg and fry stages of trout from off-site sedimentation during
construction.
3. Bridges are recommended for all permanent crossings of streams, floodplains and
associated wetlands to eliminate fill in active streams and floodplains. Floodplain
Mailing Address: Division of Inland Fisheries 1721 Mail Service Center Raleigh, NC 276yy-1"%11
Telephone: [phone] Fax: [phone]

Sherwood Estates, Cove Creek Page 2
August 21, 2008
capacities and floodplain functions should be maintained or restored. Where culverts
must be used, culverts should be designed and constructed to ensure passage of storm
events and passage of aquatic organisms during low flow conditions. Culverts should
be as short as possible and culverts should not be used for non essential or non linear
crossing purposes. Culverts 48" diameter or larger must be buried at least a foot
(12")below the streambed. Culverts less than 48" diameter must be buried to a depth
equal to or greater than twenty (20) percent of their diameter. Depth of burial must
be based on the stream's natural thalweg depth. Culverts should be aligned and
situated so that no channel realignment or widening is required unless such
modification will improve natural conditions. Widening of the stream channel at the
inlet or outlet of the culvert structure causes a decrease in water depth and velocity
causing sedimentation impacts and reduction of aquatic passage. Piping should be
large enough to prevent high velocity erosion (faucet effect) on the downstream end
and erosive swirling on the upstream end. Bottomless arch culverts should be large
enough and installed in a manner that a) the active stream and bank full benching can
be accommodated within the structure and b) significant floodwaters can access the
floodplain without structural or riparian zone damage. Flat concrete aprons between
wing-walls must not be used. Riprap must not be placed in the streambed unless
absolutely necessary and if used in channel, it must provide natural channel
dimensions. If multiple barrels are installed, base flow barrels should be installed as
indicated above while additional barrels should be placed with floors located at the
active floodplain or bank full elevation. These elevated barrels should be connected
to the active floodplain or bank full benches to ensure natural stream dimensions for
the base flow channel with sufficient water depth during low flows and drought
conditions to accommodate normally anticipated aquatic movement. If culverts are
long and/or sufficient slopes exist, alternating baffles should be provided in the base
flow barrel in a manner to conform to channel bends upstream and downstream, to
mimic natural meanders, to prevent upstream scour and downstream deposition, to
move and contain typical bed load materials, and to provide resting areas for aquatic
species. When multiple barrels are used, at least one barrel should be designed and
constructed with a floor material easily used by terrestrial wildlife. Plastic pipes
should be corrugated (not smooth or slick) on the inside so that bed load materials can
be established to provide and maintain natural substrates.
4. Remaining jurisdictional waters and wetlands should be buffered, either through
protection or provision of undisturbed forested buffer zones. Buffers should be
permanently preserved as common contiguous forest areas instead of being
subdivided into portions of individual lots. For streams that do not support federally
listed threatened or endangered aquatic species, we recommend 50' intermittent and
100' perennial stream buffers. Maximum available buffers should be provided;
however, the twenty-five (25) foot trout buffer should remain undisturbed to the
maximum extent practicable.
5. Sediment and erosion control measures should adhere to the design standards for
sensitive watersheds (15A NCAC 4B .0124).

Sherwood Estates, Cove Creek Page 3
August 21, 2008
6. If any concrete will be used, work must be accomplished so that wet concrete does
not contact stream water.
7. Heavy equipment should be operated from the bank rather than in the stream channel
in order to minimize sedimentation and reduce the likelihood of introducing other
pollutants into the stream.
8. Temporary or permanent native herbaceous vegetation should be established on all
bare soil within five (5) days of ground disturbing activities in the twenty-five (25)
foot trout buffer to provide long-term erosion control. Natural fiber matting is
recommended over plastic matting that can impinge and entrap small animals.
Onsite vegetation and materials may be used for stream bank stabilization when
practicable.
Thank you for the opportunity to review and comment on this project during the early planning
stages. If you have any questions regarding these comments, please contact me at 336-769-9453.
E-copy: Sue Homewood, DWQ-WSRO