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Intent To Prepare a Joint Environmental Impact Statement/ Environmental Impact Report/Feasibility Study (EIS/EIR/FS) for Bolinas Lagoon Ecosystem Restoration Project, Marin County, CA

Note: EPA no longer updates this information, but it may be useful as a reference or resource.

 [Federal Register: April 9, 1998 (Volume 63, Number 68)]
[Notices]               
[Page 17392-17393]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr09ap98-51]

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DEPARTMENT OF DEFENSE

Department of the Army; Corps of Engineers

 
Intent To Prepare a Joint Environmental Impact Statement/
Environmental Impact Report/Feasibility Study (EIS/EIR/FS) for Bolinas 
Lagoon Ecosystem Restoration Project, Marin County, CA

AGENCY: U.S. Army Corps of Engineers, DoD.

ACTION: Notice of intent.

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SUMMARY: Pursuant to Section 102(2)(c) of the National Environmental 
Policy Act (NEPA) of 1969 as implemented by the Council on 
Environmental Quality regulations (40 CFR parts 1500-1508), the 
California Environmental Quality Act (CEQA), the Department of the Army 
and Marin County hereby give notice of intent to prepare a joint 
Environmental Impact Statement/Environmental Impact Report/Feasibility 
Study (EIS/EIR/FS) for the Bolinas Lagoon Ecosystem Restoration 
Project, Marin County, California. The U.S. Army Corps of Engineers 
proposes to restore the ecosystem by increasing the tidal prism (volume 
of water exchanged on tidal cycles) or by other feasible alternatives. 
In accomplishing this project, the Corps could dredge up to four 
million cubic yards (MCY) of sediment. Ocean disposal as well as other 
dredged material disposal options are under consideration.

FOR FURTHER INFORMATION CONTACT:
Written comments and questions regarding the scoping process or 
preparation of the EIS/EIR/FS may be directed to Craig Vassel, U.S. 
Army Corps of Engineers, San Francisco District, 333 Market Street, 
717P, Seventh Floor, San Francisco, CA 94105-2102, (415) 977-8546, Fax: 
415-977-8695, Email: cvassel@smtp.spd.usace.army.mil.

SUPPLEMENTARY INFORMATION: The U.S. Army Corps of Engineers and Marin 
County will be the lead agencies in preparing the combined EIS/EIR/FS. 
The Gulf of the Farallones National Marine Sanctuary, Point Reyes 
National Seashore, and Golden Gate National Recreation Area will be 
cooperating agencies. The EIS/EIR/FS will provide an analysis 
supporting both the requirements of NEPA and CEQA in addressing impacts 
to the environment which may result from dredging the lagoon and 
disposing of dredged sediments.

1. Proposed Action.

    The Corps will study alternatives for restoring the ecosystem of 
Bolinas Lagoon with emphasis on increasing tidal exchange.

2. Project Alternatives.

    The Corps Reconnaissance Report (2/98) identified four possible 
actions to restore lost tidal and subtidal habitat through increasing 
tidal prism and improving circulation within the lagoon:
    a. Removing the deltaic formation (accumulated sediment) at the 
mouth of Pine Gulch Creek
    b. Reestablishing the North Channel (between Kent Island and 
Bolinas) and its tributaries.
    c. Opening the Seadrift Lagoon to unrestricted tidal exchange with 
Bolinas Lagoon.
    d. Removing fill material on the east side of the Seadrift Spit.

3. Availability of EIS/EIR/FS.

    The Draft EIS/EIR/FS should be available for public review in Fall 
2000.

4. Purpose and Need for Project.

    Bolinas Lagoon is the centerpiece of an estuary system that is 
considered to be an ecological treasure due to the diversity of species 
that either inhabit or use the area for migration purposes. Bolinas 
Lagoon provides productive and diverse coastal open water, mudflat, and 
marsh environment for fish, waterbirds, and marine mammals. Several 
types of habitat are found in the lagoon: subtidal, intertidal, marsh, 
riparian, sand bar, and beach.

5. Study Area Description.

    Located on the Pacific coast of Marin County, the study area 
includes all of Bolinas Lagoon (1100 acres, 445 hectares, 1.7 square 
miles) and its watershed (17 square miles). Triangle-shaped Bolinas 
Lagoon is located on the Pacific coast of Marin County. Bolinas Ridge 
forms one side and the sand spit of Stinson Beach forms another. The 
watershed includes several creeks, including several that descend 
steeply from Bolinas Ridge. Half of the watershed is drained by the 
longest creek, Pine Gulch Creek, which follows the San Andreas Rift 
Valley and forms a delta in Bolinas Lagoon.

6. Larger Habitat Complex.

    The Lagoon is part of a much larger protected natural habitat 
complex including Pt. Reyes National Seashore, Golden Gate National 
Recreation Area, Central California Coast Biosphere Reserve, Mount 
Tamalpais State Park, and Audubon Canyon Ranch and the Gulf of the 
Farallones National Marine Sanctuary (GFNMS). The Lagoon tidelands are 
owned by Marin County and managed as the Bolinas Lagoon Open Space 
Preserve by the Marin County Open Space District (MCOSD).

7. The problem: loss of Tidal Prism.

    The tidal prism of an estuary or lagoon is the volume of water 
exchanged between lagoon and ocean during a tidal cycle. For Bolinas 
Lagoon, high tide (MHHW) is 2.4 feet above the NGVD datum. Low tide 
(MLLW) is 1.9 feet below the datum. Therefore, the tidal range is 4.3 
feet. Tidal prism influences the dynamic equilibrium of the entrance 
channel and bathymetry (depth contours) of the lagoon. Larger tidal 
prisms more effectively scour and remove material, leading to deeper 
and wider channels. As tidal prisms decline within lagoons, 
sedimentation rates rise and entrance channels begin to experience 
temporary closure. The lagoon eventually transforms into a salt marsh 
and eventually a meadow.

8. Risk of Closure.

    Estimates are that the natural tidal prism of Bolinas Lagoon is 200 
million cubic feet (mcf). Today the tidal prism is about 90 mcf. The 
tidal prism of Bolinas Lagoon has been reduced by 22% in the 20-year 
period between 1968 and 1988, a volume of 28 mcf. The rate of decline 
is about 1.4 mcf per year (52,000 cy). Risk of closure may occur

[[Page 17393]]

when the tidal prism is reduced to 25 mcf.

9. Sedimentation History.

    Over the last 150 years, much of the lagoon's richest subtidal and 
intertidal habitat has been lost through sedimentation. There is a 
growing concern about the long-term health of the lagoon. Past human 
impacts on the lagoon contributing to the subtidal and intertidal 
habitat reduction include poor watershed management practices such as 
logging, fires, agriculture, and grazing. This has resulted in higher 
than normal sediment loads conveyed into the lagoon. Other factors that 
may increase sedimentation include placement of fill in the lagoon and 
the diversion and manipulation of watercourses entering the lagoon and 
material entering the lagoon through the ocean entrance. It is 
estimated that from 1968 to 1988 Bolinas Lagoon lost 40% of its 
subtidal habitat as it was converted to emergent marsh and uplands.

10. 1906 Earthquake

    The biggest historic change in tidal prism occurred during the 1906 
earthquake, when Bolinas Lagoon subsided one foot over most of its 
area, increasing the tidal prism by about 50 mcf.

11. Ecosystem Restoration Goal

    The goal of ecosystem restoration work performed at Bolinas Lagoon 
is to restore intertidal and subtidal habitat and stop further loss of 
these habitats through restoring tidal prism and improving circulation 
within the basin, while maintaining key mudflats, marsh vegetation, and 
other areas of biological importance.

12. Feasibility Study

    The five-phase Feasibility Study will identify and evaluate 
measures to restore lost tidal prism and reduce the rate of 
sedimentation as follows:

a. Define existing conditions and Formulate Alternatives

    Phase One will investigate existing physical and environmental 
conditions restoration needs and constraints of the area. The future 
without-project conditions in the study area will be projected. Input 
on the ecosystem will be sought from resource agencies and the public. 
Public scoping workshops will be held both at the Marin Civic Center 
and the Stinson Beach Community Center.

b. Alternative Development

    During Phase Two, tidal hydraulic modeling of the preliminary 
alternatives will be completed and economics and environmental impacts 
studied.

c. Detailed Evaluation

    In Phase Three, preliminary alternatives will be evaluated and 
environmental benefits of the ecosystem restoration alternatives will 
be qualified. A draft Fish and Wildlife Coordination Act Report 
including a Habitat Evaluation Procedure (HEP) will be prepared to help 
provide the basis for identifying the most cost-effective alternative 
acceptable to the agencies and community.

d. Draft Report Preparation

    Phase Four involves preparing the draft Feasibility Report and 
Environmental Impact Statement/Report (EIS/R). The EIS/R will analyze 
all reasonable alternatives and evaluate compliance with federal and 
state environmental requirements. A formal public review and comment 
period will be started.

e. Final Report Preparation

    The last phase of the study includes preparing the final 
Feasibility Report recommending a preferred alternative and completing 
the final EIS/R which will respond to all comments on the draft EIS/R. 
The feasibility study will conclude with the issue of the Division 
Engineer's Notice. Construction would follow.

13. Workshop/Scoping

    Two Workshop/Scoping meetings will be held on Thursday April 16. 
The first is intended mainly for local, state, and federal agencies and 
organizations. The second is all interested parties.
    Workshop/Scoping meeting locations:

9:00-12:00  Green Room, Marin Veterans' Memorial Auditorium, Marin 
Civic Center, San Rafael, CA
6:30-9:30  Stinson Beach Community Center, Stinson Beach, CA
Gregory D. Showalter,
Army Federal Register Liaison Officer.
[FR Doc. 98-9415 Filed 4-8-98; 8:45 am]
BILLING CODE 3710-19-M

 
 

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