McInnis Marsh Beneficial Dredge Sediment Reuse and Tidal Wetlands Restoration Project
McInnis Marsh and South Fork of Gallinas Creek, City of San Rafael, Marin County; Measure AA Region: North Bay
Vital Fish, Bird and Wildlife Habitat Program; Shoreline Public Access Program
This funding will enable the County of Marin to further preliminary designs, collect data and perform technical studies, prepare CEQA documents, and prepare regulatory permit applications for the McInnis Marsh Beneficial Dredge Sediment Reuse and Tidal Wetlands Restoration Project, which will improve future tidal restoration potential of the McInnis Marsh Basin in Marin County by restoring 22 to 30 acres of diked wetlands and the reversal of subsidence across 140 acres of marsh.
The project includes designing to 65% and additional planning for dredged sediment placement. The planning and design outcomes will be documented in a Basis of Design Report. In addition, the project will continue discussions with the Bay Restoration Regulatory Integration Team (BRRIT), collect data, and conduct technical studies to inform preparation of permit applications and an Environmental Impact Report. McInnis Park includes approximately 2.75 miles of public trail, including trails around the perimeter of the Main Basin and southern McInnis Marsh. These trails provide important connections to adjacent segments of the San Francisco Bay Trail network. The project will facilitate improved quality of tidal marsh and non-tidal wetland habitats adjacent to the trail and, therefore, the experience of trail users. The project will plan for modifications to allow for the breaching of the outer berm in the southern marsh. The project will also plan for significant improvements to the public’s low-tide, small boat access to the creek channel.
The project will contribute to recovery and resilience of degraded baylands habitats by: 1) restoring 22 to 30 acres of diked wetlands to sea level rise through tidal hydrology restoration and tidal channel network creation; 2) preparing the 140-acre Main Basin to support future tidal marsh habitat restoration and to improve resilience to future sea level rise by beneficially re-using approximately 110,000 cubic yards of clean dredge sediments from Gallinas Creek; 3) applying a geomorphic-based design for dredging along approximately 1.8 miles of the South Fork of Gallinas Creek to support recreational small boat access and provide a pilot scale proof of concept for the geomorphic dredging approach; 4) engaging with community and tribal partners, neighboring landowners, and land managers to garner support for tidal restoration in the Main Basin; and 5) improving the overall trail system in the marsh.
