Microsoft Word - R-2915D_IP modification_SAW 2012-00882, DWR 20140762 v.7 _NCWRC Comments

North Carolina Wildlife Resources Commission
Cameron Ingram, Executive Director
April 28, 2022
Lori Beckwith
U.S. Army Corps of Engineers,Asheville Regulatory Field Office
151 Patton Avenue,Room 208
Asheville,NC 28801
Dave Wanucha
NCDEQ,DWR
450 Hanes Mill Road, Suite 300
Winston Salem,NC 27105
Dear Ms. Beckwith and Mr.Wanucha,
SUBJECT: Comments on Request for Modification to Section 404 Individual Permit and Section 401
Water Quality Certification for US 221 Widening from US 421 to US 221
Business/NC88,Watauga and Ashe Counties
R-2915D, SAW 2012-00882,DWR 20140762 v.6
The North Carolina Department of Transportation(NCDOT) applied for a modification to the Section 404
Individual Permit and Section 401 Water Quality Certification for the subject project. I visited the project
site on April 21,2022. Comments on the application from the North Carolina Wildlife Resources
Commission(NCWRC)are offered in accordance with applicable provisions of the state and federal
Environmental Policy Acts (G.S. 113A-lthrough 113-10; 1 NCAC 25 and 42 U.S.C. 4332(2)(c),
respectively),the Clean Water Act of 1977 (33 U.S.C. 466 et seq.), and the Fish and Wildlife
Coordination Act(48 Stat.401, as amended; 16 U.S.C. 661-667d).
The modification is requested to place 320 feet of an unnamed tributary to Beaver Creek(classified C
Tr+)in a pipe and inlet system to address erosion and stabilize a potential failure of a roadway fill slope.
The stream,which flows along the toe of the fill slope,is incised and carries a high sediment load due to
severe erosion(see photos). It appears fishless at the site but Beaver Creek downstream is designated
hatchery supported trout water that also supports a wild brown trout population despite its poor habitat.
Mailing Address: Habitat Conservation • 1721 Mail Service Center • Raleigh,NC 27699-1721
Telephone: [phone] • Fax: [phone]

R-2915D Page 2 April 28,2022
Watauga and Ashe Counties
Above the proposed pipe and slope repair is very steep channel that flows out from a breached basin that
existed before R-2915D was constructed.
The NCWRC typically recommends that such large stream impacts be avoided whenever possible,
particularly in trout-supporting watersheds. However, either piping of this stream or armoring appears
necessary here to address the stream scour. The NCWRC supports efforts to reduce the sediment loading
that Beaver Creek is likely receiving from this drainage.
While supportive of the project objectives,the NCWRC is nonetheless concerned that the project may
displace or not fully address the stream channel erosion in this drainage. In particular,the 320 feet of 36"
HDPE will have an approximate 10% slope that may create erosive velocities and more channel
degradation further downstream. The NCWRC recommends adding outlet protection, such as a
preformed scour hole like that shown for the storm drain outlet on the opposite side of US 221 (Sta
613+50 R). Additional hydraulic analysis might also help determine where erosive velocities may be a
concern, and outlet protection needed, elsewhere in the vicinity of the proposed repair work.
Thank you for the opportunity to review and provide recommendations on this project. Please contact me
at [e-mail] or(828)476-1966 if you have any questions about these comments.
Cordially,
Dave McHenry, CWRC Western DOT Coordinator
ec: Michael Turchy,NCDOT ECAP
Kevin Hining,NCDOT Division 11 DEO
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Stream within(left)and below impact area(right).Photo right is 42"(?) CMP inlet at Sta. 617+80 L.