Oregon Inlet Q2 2023 Maintenance Event Request DCM

COASTAL PROTECTION ENGINEERING OF NORTH CAROLINA, INC
4038 MASONBORo Loop ROAD
COASTAL WILMINGTON, NC 28409
PROTECTION 910-399-1905
ENGINEERING
March 23, 2023
Heather Coats
Beach & Inlet Management Project Coordinator
North Carolina Division of Coastal Management
127 Cardinal Drive
Wilmington, NC 28405
Subject: Oregon Inlet Channel Maintenance Project — Written Notice of Intent to
Conduct Maintenance Dredging in Q2 of 2023 (Major Permit #49-19)
Dear Ms. Coats:
The Division of Coastal Management (DCM) issued a CAMA Major Permit (#49-19) for the
maintenance of Oregon Inlet on June 24, 2019. This permit was subsequently modified on December
21, 2021 and has a current expiration date of December 31, 2024. This letter serves as a written notice
of Dare County's intent to initiate dredging under the subject permit.
Dare County intends to utilize the dredge Miss Katie to maintain the Ocean Bar Channel at Oregon Inlet,
portions of the channel that run from Oregon Inlet to Hells Gate referred to as the Alternate Route, and
portions of Old House Channel Range 1. Dredged material willbe disposed in proximity to the remaining
portion of the Bonner Bridge and in the nearshore disposal area offshore Pea Island, in accordance with
the permits. As previously coordinated with your office, dredging has been conducted in the Ocean Bar
Channel since August 2022 and in the portion of the Oregon Inlet to Hells Gate channel referred to as
the Alternate Route since October 2022. Dredging is scheduled to continue as needed from April 1
through June 30 2023. Given the frequent need for maintenance dredging at Oregon Inlet, Dare County
anticipates the Miss Katie will perform regular maintenance work under the subject permit for the
foreseeable future. However, this correspondence is specifically noticing for dredge operations
anticipated to occur in Q2 of 2023 (April through June.
The forthcoming dredge maintenance event is anticipated to be limited to dredging within the portions
of the Oregon Inlet Ocean Bar Channel, the Oregon Inlet to Hells Gate Channel (Alternate Route, and
Old House Channel Range 1 as shown on the attached plans dated March 22, 2023. Dredging of the
Ocean Bar Channel will follow best water as determined through coordination with the USACE
Wilmington District Navigation Branch. Dredging will be limited to a 400-foot-wide channel with
bottom elevation of -16 ft. MLLW. Dredging of the Oregon Inlet to Hells Gate Channel (Alternate
Route will be limited to the specific footprint shown on the attached plans to comply with requirements
of the Dept. of Army permit. Dredging in this channel will be limited to a 100-foot-wide channel with
bottom elevation of -10 ft. MLLW. Dredging of the Old House Channel Range 1 Channel will be limited
to the specific footprint shown on the attached plans, which includes a 100-foot-wide channel with
bottom elevation of -12 ft. MLLW. The disposal sites permitted include a nearshore disposal site located
off the northeastern end of Pea Island and disposal in proximity to the deep scour holes beneath the
Herbert C. Bonner Bridge. Because the majority of the existing Bonner Bridge has been demolished, the

County's permit limits the disposal to the areas surrounding the remaining bridge pilings which extends
from the shoulder of Pea Island approximately 1,500 feet. This remaining portion of the bridge is known
as the "training structure". The training structure has been left in place to help keep the inlet navigable
after removal of the majority of the old bridge. The intention for keeping the training structure in place
is to forestall Davis Slough from returning to the prevailing deep -water channel through which it flowed
prior to the construction of the old bridge. The presence of the training structure, therefore, effectively
serves to minimize the risk that the deep -water channel will migrate south and threaten the integrity of
the Pea Island terminal groin.
Based on the latest bathymetric surveys conducted for the Ocean Bar Channel by EJE Dredging on
December 3, 2022, the estimated volume of material required to be removed to achieve the design
channel dimensions for the proposed channel is approximately 77,000 cubic yards. However, significant
dredging has been done on the ocean bar since that time. We are awaiting updated surveys of the Bar
Channel, anticipated to be completed by the USACE as weather permits and will update the drawings
and volumes when data is available. Based on bathymetric surveys conducted by the USACE Wilmington
District Navigation Branch on February 9, the estimated volume of material required to be removed to
achieve the design channel dimensions for the proposed Oregon Inlet to Hells Gate Channel (Alternate
Route) is approximately 33,800 cubic yards. Based on bathymetric surveys conducted by the USACE
Wilmington District Navigation Branch on February 15, 2023, the estimated volume of material required
to be removed to achieve the design channel dimensions for Old House Channel Range 1 is
approximately 7,200 cubic yards.
Permit Condition #5 of the CAMA Major Permit states, "Prior to the initiation of any dredging activities
autbori.�ed by this permit, the permittee sball, in coordination witb the N. C. Department of Natural and Cultural Resources
(DNCR), demlop and implement an arcbaeological survey of the proposed project area. Initiation of permitted dredging
activities sball not begin until written approval is obtained from DNCR, and a copy of such approval bas been submitted
to the Division of Coastal Management."
In a letter dated August 15, 2022, DNCR stated thatwith the present alignment of the Ocean Bar Channel
the dredging project will avoid the assumed coordinates of the potentially National Register of Historic
Places (NRHP) eligible shipwreck W.G. Townsend. Through further coordination, a 100-foot radius
buffer has been established around the coordinates of the W.G. Townsend to avoid any impacts. In a
letter dated July 29, 2022, DNCR concurred to the USACE Wilmington Districts request for emergency
dredging within the specific footprint of the "Western Alternate Route", which is the channel referred to
in the attached plans as Hells Gate to Oregon Inlet (Alternate Route). Based on this previous
coordination with the DNCR for Q3-2022, the fact that the channel location of both the Ocean Bar
Channel and the Alternate Route are the same as proposed for Q3-2022, and the fact that Old House
Channel Range 1 is a fixed location that has previously been dredged by the USACE, Dare County and
its consultants are of the opinion that CAMA Major Permit Condition #5 has been satisfied.
In accordance with Permit Condition #7, Dare County worked with the USACE regulatory project
manager and EJE Dredging to confirm the dredge has been constructed in accordance with the USACE
hopper dredge plant specifications and that the dredge plant complies with the conditions of the Corps'
2004 FONSI. The inspections were signed off on by the County, EJE Dredging, and Josh Pelletier on
August 26, 2022.
We look forward to scheduling a pre -construction conference in the near future, in accordance with
Condition #10.

Please feel free to contact me anytime for further clarification or explanation of the project.
Very truly yours,
COASTAL ROTECTION ENGINEERING OF NORTH CAROLINA, INC.
Ken Willson
Project Manager
CC:
Robert Outten, Dare County
Barton Grover, Dare County
Greg Bodnar, NC D CM
Josh Pelletier, USACE Washington, NC Regulatory Office
Robert Tankard, NC DWR
Sabrina Henry, NPS