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Environmental Services

Dean Messer, Chief

3500 Industrial Blvd.
West Sacramento, CA 95691
(916) 376-9699

Mailing Address:
P.O. Box 942836
Sacramento, CA 94236-0001



FRPA-Decker Island Tidal Habitat Restoration Project

Decker Island Tidal Habitat Restoration Project

The Decker Island Tidal Habitat Restoration Project is an approximately 140-acre tidal restoration project in southern Solano County proposed by DWR. Decker Island was created by the United States Army Corp of Engineers during the construction of the Sacramento River Deep Water Ship Channel in the early 1900s which cut through a portion of the alluvium deposits of Montezuma Hills. The island is bordered on the west by the Sacramento River and the east and south by Horseshoe Bend. DWR is the CEQA Lead Agency for this Project.

The Project is intended to partially fulfill the 8,000 acre tidal habitat restoration obligations of DWR pursuant to the 2008 U.S. Fish and Wildlife Service Delta Smelt Biological Opinion (BiOp) for long-term coordinated operations of the State Water Project (SWP) and the federal Central Valley Project (CVP). Because restoration of tidal habitat would provide access for salmonid rearing at Decker Island, the Project would also be consistent with the 2009 National Marine Fisheries Service Salmonid BiOp for SWP/CVP operations.

The goal of the Project is to restore unrestricted tidal connectivity to the interior of Decker Island to create tidal wetland, associated high marsh, and riparian habitats on the site to benefit native fish species.  The project objectives include:

  1. Enhance habitat appropriate for spawning and/or rearing salmonids, Delta Smelt, and other native fish species;

  2. Enhance available productivity for native fish within and adjacent to the restoration site; and

  3. Provide connectivity to the marsh plain for migrating salmonids.

Achieving project objectives would result in benefits to special status species in and around the project area. Enhanced habitat by providing a larger tidal regime would expand emergent marsh habitat for use by Delta Smelt and juvenile salmonids as well as other listed species like California black rail (Rallus jamaicensis cotumiculus) and tricolored blackbird (Agelaius tricolor). Productivity from increased emergent marsh, and associated high marsh and floodplain, would provide food web benefits to rearing salmonids, Delta Smelt (Hypomesus transpacificus), and Longfin Smelt (Spirinchus thaleichthys).

Associated Decker Island Documents