20240361 Ver 1_01_Trinitie Trail_CoverLetter_20240304

Kimley>»Horn
March 1, 2024
Mr. Shane Staples
U.S. Army Corps of Engineers
Wilmington Regulatory Field Office
2407 West Fifth Street
Washington, North Carolina 27889
Mr. Garcy Ward
NC Division of Water Resources
401 & Buffer Transportation Permitting
943 Washington Square Mall
Washington, NC 27889
RE: Nationwide Permit 3 Application
Structure Replacement of Trinitie Trail Culvert — SA W-2023-01268
Southern Shores, Dare County, North Carolina
Mr. Staples and Mr. Ward,
On behalf of our client, the Town of Southern Shores, Kimley-Horn is submitting the attached Nationwide
Permit (NWP) #3 request for the above referenced project located in Southern Shores, Dare County, NC.
The project proposes to remove the existing aluminum pipe arch culvert and place a prestressed concrete
cored slab over Canvas Back Canal along Trinitie Trail. The existing culvert has experienced significant
settlement on its sides leading to an uneven roadway surface that is prone to ponding water during rain
events. Additionally, the current vertical grade of the roadway does not meet current design standards for
safe stopping sight distance, leading to an unsafe "blind" crest going over the structure. Canvas Back
Canal is a navigable water, however we have coordinated with the US Coast Guard and obtained an
Advance Approval Exemption for the proposed project. The approval letter is attached as part of this
permit package for reference.
Kimley-Horn staff conducted a stream, wetland, and coastal resource delineation within the project study
area on May 10, 2023 and identified one stream (Canvas Back Canal). A Preliminary Jurisdictional
Determination was issued by Mr. Shane Staples of the USACE on October 2, 2023 (SAW-2023-01268).
The proposed project will include the removal of the existing culvert resulting in unavoidable impacts to
Canvas Back Canal. The existing wooden bulkheads are located outside of the existing culvert and will
not be removed or modified as part of the proposed project. A prestressed concrete cored slab will be
placed on the existing alignment with traffic being detoured offsite during the construction period.
Approximately 0.021 acres (91 LF) of permanent no -net loss (P-NNL) stream impacts will result from
driving sheet piles behind the existing pipe arch to shore the fill behind it, slightly widening the existing
channel, and removing the existing culvert for the placement of the proposed prestressed concrete cored
slab. There will be no impacts to the canal floor and the flow will be maintained throughout construction
with no disruption to natural tidal ebbs and flows. Additionally, a total of approximately 0.013 acre (91 LF)
of temporary impacts would result from the proposed project due to the temporary construction access
needed to remove the existing culvert and place the proposed new prestressed concrete cored slab
within the project corridor. Temporarily impacted areas will be returned to pre-existing contours upon
completion of the project. P-NNL and temporary impacts are similar in length and different in acreage due
to the orientation of the existing culvert. A turbidity curtain will be installed within Canvas Back Canal prior
to initiating construction activities in the corridor to prevent turbid water from leaving the in -water work
area. The Town of Southern Shores seeks to ensure the safe navigability of the canal after the
replacement of the culvert with the bridge, therefore no riprap will be placed within the canal or below the
existing edge of water.

Kimley>»Horn
All permanent stream impacts will result in no net loss of aquatic function and therefore compensatory
mitigation is not proposed as part of this permit application.
To assist with the processing of this application, the following information is included:
• ePCN Application Form
• Signed Agent Authorization Form
• Figures
• USACE Pre -Jurisdictional Determination Approval (SAW-2023-01268)
• Email Coordination with the North Carolina Wildlife Resource Commission
• US Coast Guard Advance Approval Exemption Letter
• Permit Impact Drawings
• Project Plan Sheets
• U.S. Fish and Wildlife Service Official Species List
• NCDWR 401 Application Fee of $323
If you need any additional information to assist in your review of this NWP application, feel free to contact
me at 919-677-2215 or Emma. [e-mail].
Sincerely,
Emma Radford, WPIT, CA
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