19970616 Ver 1_Modifications_20021021

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STATE OF NORTH CAROLINA
DEPARTMENT OF TRANSPORTATION
MICHAEL F. EASLEY LYNDO TIPPETT
GOVERNOR SECRETARY
U. S. Army Corps of Engineers
Regulatory Field Office
6508 Falls of the Neuse Road, Suite 120
Raleigh, North Carolina 27615
ATTN: Ms. Jean Manuele
NCDOT Coordinator
Subject: Watauga County, US 421 new location from South Fork New River in Boone to
the Blue Ridge Parkway in Deep Gap. USACE Action ID No. 199707161, DWQ)
project No. 970616, Federal Aid Project No. FR-86-1(6), State Project No.
8.1750601, TIP No. R-529BA., BB & BD.
The North Carolina Department of Transportation is requesting a modification to
Department of the Army Permit No. 1997071.61. Department of the Army (DOA) Permit No.
199707161 was issued on May 4, 1998 and authorized impact by fill or excavation to 1.32 acres
of wetland and 13,461 linear feet of stream channel. DOA Individual Permit No. 199707161
required channel relocations to be done utilizing natural channel design instead of placing the
stream in what is essentially a straight rip-rap lined ditch.
Since the original permit was issued and the project let to construction, the design of a
channel relocation for an unnamed tributary to Gap Creek has changed.. The stream channel in
question is just west of the US 421 and US 221 intersection.
October 11, 2002
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OCT 2 t 3y I
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In the original design, the channel relocation was designed as a straight, rip-rap lined
channel. The NCDOT, in coordination with the USACE, the NCWRC, the NCDWQ, and other
agencies, revised the design in January of 1999 to comply with the permit requirement to
incorporate natural channel design into all channel relocations. A design was agreed upon and approved by tea gencies. It was subse quentlYincorPorated into the construction plans. Since
construction began on the stream relocation, there have been numerous problems. To date, the r _.r
NCDOT and its contractors have not been able to build the channel relocation as designed and C:-?
permitted. The soil in the project area is extremely unstable and the slope too severe to allow fa,r
MAILING ADDRESS:
NC DEPARTMENT OF TRANSPORTATION
PROJECT DEVELOPMENT AND ENVIRONMENTAL ANALYSIS
1548 MAIL SERVICE CENTER
RALEIGH NG 21699-1548
TELEPHCCNE' 919-733-3141
FAX [phone]
WEBSITE. WWW NCDOT ORG
LOCATION:
TRANSPORTATION BUILDING
1 SOUTH WILMINGTON STREET
RALEIGH NC.
the current design to be constructed and stabilized. The NCDOT has consulted with the USACE
and the NCWRC to determine what can be done to correct the problem. After reviewing all the
available options, including abandoning natural channel design in favor of a rip-rap "ditch", the
NCDOT decided to go with an amended natural channel design. The new design incorporates a
more conservative channel design with ess sinuosity an more in-channel structure. The new
design will reduce the chance of catastrophic bank failure and provide a more stable stream.
However, due to the reduction in sinuosity, the new design is approximately 918.4 feet shorter
than the original design. Therefore, the NCDOT will now need to go off site to rep acl e t e ost
channel.
The NCDOT proposes to contract with the NCWRC to provide the additional miti at
at a 2 to 1 ratio. The NCDOT will uurc ase .837.0 linear feet of stream mitigation from the
Please find attached a copy of the proposed design. The NCDOT requests that DOA
Individual Permit No. 199707161 be modified to reflect the new design and mitigation proposal.
Additionally, in order to allow time to construct the new channel design and get it stabilized
immediately, the NCDOT requests that the in-water work moratorium begin on Nov. 15 instead
of October 15, as is currently required.
By copy of this letter, the Department also requests that the Division of Water Quality
modify the §401 Water Quality Certification (DWQ Project No. 970616). If you have any
further questions or would like additional information, please don't hesitate to call. Thank you
for your time and consideration.
Sincerely,
? U, ? ? .1
Gregory J. Thorpe, Ph.D.
Environmental Management Director
Project Development and Environmental Analysis Branch
cc: w/attachment
Mr. David Franklin, USACE, Wilmington
Mr. John Dorney, Division of Water Quality
Mr. Ron Linville, NCWRC
w/o attachment
Mr. John Alford, P.E., Roadway Design
Mr. David Rhodes, P.E., Programming and TIP
Ms. Debbie Barbour, P.E., Highwmy Design
Mr. David Chang, P.E., Hydraulics
Mr. Mark Staley, Roadside Environnmental
Mr. Carl McCann, Division I 1 Engineer
Mr. Greg Perfetti, P.E., Structure E)esign
Mr. Heath Slaughter, DEO-Divisicnn 1 I