20151027 Ver 1_WRC Comments_20150911

E North Carolina Wildlife Resources Commission IQ
Gordon Myers, Executive Director
September 11, 2015
Ms. Tasha Alexander
U.S. Army Corps of Engineers, Regulatory Branch
151 Patton Avenue, Room 208
Asheville, North Carolina 28801 -5006
SUBJECT: Lake Tomahawk Dredging
Tomahawk Branch, Buncombe County
Dear Ms. Alexander:
Biologists with the North Carolina Wildlife Resources Commission (NCWRC) reviewed an
application to dredge a large forebay area in Lake Tomahawk consisting of 0.71 acres
Tomahawk and dredge 180 ft of Tomahawk Branch in Buncombe County. On September 4,
2015, I spoke with Jesse Gardner, who is acting as a project consultant on behalf of the Town of
Black Mountain. Our comments on this application are offered for your consideration under
provisions of the Clean Water Act of 1977 (33 U.S.C. 466 et. seq.) and Fish and Wildlife
Coordination Act (48 Stat. 401, as amended; 16 U.S.C. 661- 667d).
The project should not affect trout, and project activities do not need to be avoided during the
trout moratorium. However, the upper Swannanoa River has a small population of Eastern
Hellbender (Cryptobranchus alleganiensis, US Federal Species of Concern, NC Special
Concern), a species sensitive to excess sediment.
We are concerned about the potential for downstream sediment release during this project. The
lake level will be lowered so that the forebay area to be dredged will be isolated from the lake
levels. The applicant intends to lower the water levels in the lake with a bottom valve, which,
according to Jesse Gardner, was used approximately six months ago and resulted in a minimal
release of sediment. The lake level will be kept at this lower water level with the bottom drain
valve while dredging is performed. Mr. Gardner said that the outflows from the lake will be
monitored, and if turbid water is released, dredging work will be stopped. If this lake draining
method results in more than a minimal sediment release, we recommend that the applicant use a
surface pump to draw down lake levels instead.
Mailing Address: Division of Inland Fisheries • 1721 Mail Service Center • Raleigh, NC 27699 -1721
Telephone: [phone] • Fax: [phone]

Lake Tomahawk Dredging Page 2 September 11, 2015
Tomahawk Branch, Buncombe County
We offer the following recommendations to minimize impacts to the aquatic community:
1. Due to the presence of Eastern Hellbender in the vicinity of the project, we ask that particular
care be used to ensure that downstream sediment loss is minimized. We recommend that the
dredging area be isolated from the stream with silt fences or other sediment control measures.
2. Water released via the bottom drain valve should be monitored daily. Dredging activities
should be stopped if they result in sediment release downstream of the lake.
3. We recommend that a surface pump be used to drain the lake if the use of the bottom valve
results in more than a minimal sediment loss.
4. Matting used for stabilization should be free of nylon mesh; nylon mesh netting frequently
entangles wildlife and is slow to degrade resulting in a hazard that may last for years.
Thank you for the opportunity to review and comment on this project. Please contact me at
(828) 400 -4223 if you have any questions about these comments or need further assistance.
Sincerely,
Andrea Leslie
Mountain Region Coordinator, Habitat Conservation Program
ec: Jesse Gardner, Civil Design Concepts
Zan Price, NC Division of Water Resources