[Federal Register: May 19, 2005 (Volume 70, Number 96)]
[Notices]
[Page 28924-28926]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr19my05-56]
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DEPARTMENT OF DEFENSE
Department of the Army; Corps of Engineers
Intent to Prepare a Draft Environmental Impact Statement (DEIS)
for the Nourishment of 7.25 Miles of Beach, the Repositioning of the
New River Inlet Channel, and the Implementation of an Inlet Management
Plan, in North Topsail Beach, Onslow County, NC
AGENCY: Department of the Army, U.S. Army Corps of Engineers, DoD.
ACTION: Notice of intent.
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SUMMARY: The U.S. Army Corps of Engineers (COE), Wilmington District,
Wilmington Regulatory Field Office has received a request for
Department of the Army authorization, pursuant to Section 404 of the
Clean Water Act and Section 10 of the Rivers and Harbor Act, from the
Town of North Topsail Beach to nourish approximately 7.25 miles of
beachfront to protect residential homes and town infrastructures, and
to implement an inlet management plan with the New River Inlet to
control the positioning of the inlet channel. The new channel will be
centrally located perpendicular to the adjacent shorelines of North
Topsail Beach and Onslow Beach. The proposed source of the material for
the nourishment will be dredged from offshore borrow area(s) and from
the repositioning of the inlet. The placement of beach fill along the
Town's shoreline would result in the initial widening of the beach by
50 to 100 feet. The widened beach would be maintained through a program
of undefined periodic beach nourishment events with the material
extracted primarily from the New River Inlet.
The ocean shoreline in the Town of North Topsail Beach encompasses
approximately 11.1 miles along the northern end of Topsail Island.
Currently, the U.S. Army Corps of Engineers is developing a Federal
shoreline protection plan for parts of North Topsail Beach. This
Federal plan will only cover 3.85 miles of the southern part of the
beach. The remaining 7.25-miles of North Topsail Beach, with the
exception of two small areas, is located within the Coastal Barrier
Resource System (CBRS), which prohibits the expenditure of Federal
funds that would encourage development. Therefore, the Town is pursuing
to develop this non-Federal shoreline protection plan that will
preserve existing development and infrastructure along the 7.25 miles
of shoreline.
The channel through New River Inlet has been maintained by the COE
for commercial and recreational boating interest for over 55 years. The
COE is authorized to maintain the channel in the inlet to a depth of 6
feet mean low water (mlw) over a width of 90 feet.
DATES: A public scoping meeting for the Draft EIS will be held at Dixon
High School located on Highway 17, on June 7, 2005 at 6 p.m. Written
comments will be received until June 21, 2005.
ADDRESSES: Copies of comments and questions regarding scoping of the
Draft EIS may be addressed to: U.S. Army Corps of Engineers, Wilmington
District, Regulatory Division, ATTN: File Number 200500344, Post Office
Box 1890, Wilmington, NC 28402-1890.
FOR FURTHER INFORMATION CONTACT: Questions about the proposed action
and DEIS can be directed to Mr. Mickey Sugg, Wilmington Regulatory
Field Office, telephone: (910) 251-4811.
SUPPLEMENTARY INFORMATION: 1. Project Description. The Town of North
Topsail
[[Page 28925]]
Beach, located along the north-northeast 11.1 miles of Topsail Island,
North Carolina, is proposing to nourish approximately 7.25 miles of
beach and reposition New River Inlet channel as a means to address a
severe erosion problem that is threatening development and town
infrastructure. The entire stretch of the Town's shoreline has
experienced a considerable amount of erosion over the last 20 years due
primarily to the impact of numerous tropical storms and hurricane
during the mid to late 1990's and due to impacts of the uncontrolled
movement of the main ebb channel in New River Inlet. The Town has
stated that the shoreline erosion and residual effects of the storms
have left North Topsail Beach in an extremely vulnerable position with
regard to its ocean front development and infrastructure. They have
estimated that over $250 million in property tax value as well as
roads, water and sewer lines, and other utilities are at risk.
The project area is divided into the North Section and the Central
Section
(Note: The South Section is part of the Federal shoreline
protection plan). The North Section is further divided into two parts.
One comprises approximately 5,800 linear feet, or 1.1 mile, of the
project and is located along the northern end of the island. This area
will receive material solely from the dredging of the New River Inlet
when the channel is repositioned and realigned through the ebb tide
delta. The new channel is expected to result in widening of the north
of the Town's shoreline as the shoreline responds to the ebb tide delta
configuration that would accompany the relocated channel. In addition
to the placement of the material in the North Section, a portion of the
inlet material will be deposited on the southern end of Onslow Beach as
part of the comprehensive inlet management plan in order to maintain
the existing sediment budget on Onslow Beach. The second part of the
North Section is approximately 14,200 linear feet along the shoreline
and will receive sand from the offshore borrow site(s). The Central
Section is located both north and south of NC Hwy 210/55 Bridge and is
approximately 16,500 linear feet. Material used to widened this section
of the beach will also be obtained from the offshore borrow area(s).
2. Proposed Action. The scope of activities for the formulation of
the shoreline protection and inlet management plans for the Town of
North Topsail Beach includes: (a) Detailed geotechnical investigations
to define potential offshore borrow site(s); (b) evaluation and design
of a new channel for New River Inlet and the development of an inlet
management plan; (c) design and evaluation of beach fill sections
including an assessment of the potential impacts of the offshore borrow
area(s) on sediment transport; (d) near shore and inlet habitat
mapping; and (e) hard bottom investigations. All geospatial data
collected for the North Topsail Beach project will be included in a GIS
database developed for the project.
Potential offshore borrow areas, previously identified by work
conducted by the Wilmington District Corps of Engineers, will be
evaluated in detail using jet probes; seismic, sidescan, and
magnetometer surveys; as well as vibracores. Samples of the offshore
material collected form the jet probes and vibracores will be used to
define the preliminary boundaries of the offshore borrow area(s) and
make a preliminary determination of the compatibility of the borrow
material to the native beach material. The boundaries of the potential
borrow area(s) will take into consideration the location and extent of
hard bottom resources identified by the sidescan and seismic surveys,
as well as in-waters surveys. The boundaries of the proposed offshore
borrow site(s) will also be refined to avoid historically significant
archaeological artifacts located by the magnetometer surveys and
verified through field investigations. Once the boundaries of the
potential borrow area(s) are finalized, a final sediment compatibility
analysis will be conducted.
The beach fill designs presented in the feasibility study will be
refined by analyzing existing profiles to determine potential erosion
and storm impacts on back beach features such as vegetation,
structures, and infrastructure. Specific designs will be developed for
up to five characteristic profiles for the Central and North Sections.
Design variations will be considered at discrete beach sections where
unique upland features require special accommodation. The composite
nature of the final beach and inlet design will require a more complex
sequencing in construction operations than normally required for
renourishment projects. The method and order of operations will be
determined in order to optimize constructability and reduce costs.
Beach planform performance will be evaluated based on the numerical
modeling for the proposed projects. The GENESIS numerical model will be
used in conjunction with a wave transformation model (STWAVE) to
evaluate shoreline positions in time. The wave transformation model
will be used to determine changes in wave patterns associated with the
near shore borrow area(s). The state-of-the-art GENESIS version will be
used so that the project area may be incorporated into a single
simulation domain. The historical changes of the project area shoreline
will be used to calibrate and verify the model, using an error
minimization approach. Adjustments to the wave data used as input
within the models will be made as required to replicate observed
performance. The GENESIS model will be used to identify optimum
alongshore fill placement.
A detailed geomorphic study of New River Inlet was accomplished
during the feasibility phase of the project development. The geomorphic
study used aerial photographs to evaluate changes in New River Inlet
from 1962 and 2003 and develop relationships between the configuration
of the New River Inlet ebb tide delta and the behavior of the
shorelines on the north end of the North Topsail Beach and the south
end of Onslow Beach. The geomorphic study concluded that the most
desirable location and orientation of the channel through the ebb tide
delta, in terms of impacts on the adjacent islands, is one located
closer to North Topsail Beach and oriented essentially perpendicular to
the general alignment of the adjacent shorelines. The feasibility phase
of the project development also included a preliminary numerical model
evaluation of the impact of the relocated channel of flows and flow
distributions in the New River Inlet complex.
The next phase of the channel design will include additional
numerical model evaluations of a wider range of channel alternatives
(channel depths, widths, and locations) and will incorporate
modifications in the configuration of the ebb tide delta expected to
occur in response to the new channel. The reconfigured ebb tide delta
will also be used to determine the potential changes in wave patterns
north and south of New River Inlet and the impacts these changes could
have on longshore sediment transport and shoreline behavior.
The potential shoaling characteristics of the new channel will be
evaluated using empirical shoaling algorithms developed for inlets in
North Carolina. The propensity of the new channel to migrate to the
north and/or south and possible future changes in the channel alignment
will be based on observed changes in New River Inlet as documented by
the geomorphic analysis. The potential changes in longshore sediment
transport patterns on North Topsail Beach and Onslow
[[Page 28926]]
Beach associated changes in wave patterns together with the channel
shoaling analysis will be used to develop a with-project sediment
budget. The with-project sediment budget will be compared to the
existing sediment budget to determine sand bypassing requirements that
would be needed to maintain the existing sediment budget of the
adjacent islands.
3. Issues. There are several potential environmental issues that
will be addressed to the FIS. Additional issues may be identified
during the scoping process. Issues initially identified as potentially
significant include:
a. Potential impact to marine biological resources (benthic
organisms, passageway for fish and other marine life) and Essential
Fish Habitat, particularly Hard Bottoms.
b. Potential impact to threatened and endangered marine mammals,
birds, fish, and plants.
c. Potential impacts to water quality.
d. Potential increase in erosion rates to adjacent Onslow Beach.
e. Potential effects on military training on U.S. Marine Corps Camp
Lejeune Base.
f. Potential impacts to Navigation, commercial and recreational.
g. Potential impacts to the long-term management of New River
Inlet.
h. Potential impacts to private and public property.
i. Cumulative impacts of Inlet and Inlet channel relocations
throughout North Carolina.
j. Cumulative impacts for using inlets as sand source in
nourishment projects.
k. Potential impacts on public health and safety.
l. Potential impacts to recreational and commercial fishing.
m. The compatibility of the material for nourishment.
n. Potential economic impacts.
4. Alternatives. Several alternative borrow areas are being
considered for the proposed project. These alternatives will be further
formulated and developed during the scoping process and an appropriate
range of alternatives, including the no federal action alternative,
will be considered in the EIS.
5. Scoping Process. A public scoping meeting (see DATES will be
held to receive public comment and assess public concerns regarding the
appropriate scope and preparation of the Draft EIS. Participation in
the public meeting by federal, state, and local agencies and other
interested organizations and persons is encouraged.
The COE will also be consulting with the U.S. Fish and Wildlife
Service under the Endangered Species Act and the Fish and Wildlife
Coordination Act, and with the National Marine Fisheries Service under
the Magnuson-Stevens Act and Endangered Species Act. Additionally, the
EIS will assess the potential water quality impacts pursuant to Section
401 of the Clean Water Act, and will be coordinated with the North
Carolina Division of Coastal Management (DCM) to determine the projects
consistency with the Coastal Zone Management Act. The COE will closely
work with DCM through the EIS to ensure the process complies with all
State Environmental Policy Act (SEPA) requirements. It is the COE and
DCM's intentions to consolidate both NEPA and SEPA processes to
eliminate duplications.
6. Availability of the Draft EIS. The Draft EIS is expected to be
published and circulated sometime in early 2006, and a public hearing
will be held after the publication of the Draft EIS.
Dated: May 12, 2005.
George T. Burch,
Chief of Staff.
[FR Doc. 05-9995 Filed 5-18-05; 8:45 am]