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San Francisco Bay Delta

Cullinan Ranch Tidal Marsh Restoration Project

This project will restore 1549 acres of tidal wetlands in the San Pablo Bay National Wildlife Refuge. Cullinan Ranch was once part of an extensive network of tidal marshes in the North Bay. It was diked in the late 1800s for farming until USFWS acquired the property in 1991 and incorporated it into the San Pablo Bay National Wildlife Refuge. Subsequent restoration was delayed because of the need to protect Highway 37 from flooding associated with tidal reintroduction. Project elements include protecting existing infrastructure, and breaching and lowering levees to allow sedimentation processes to restore tidal marsh. Restoration will improve ecologic health, habitat connectivity and water quality of the lower Napa River and San Pablo Bay.

Project Facts

Recipient: Ducks Unlimited
Funding: $1,400,000 (non-federal match = $500,000/leverage = $12,375,327)
Project Period: September 2011-March 2015
Partners: US Fish and Wildlife Service, CA Department of Fish and Wildlife

Environmental Results Summary: Cullinan Ranch Tidal Marsh Restoration Project

OUTPUTS (Activities, efforts, and/or work product during project period)

OUTCOMES (Environmental results)

(1-5 yrs)


Levee improvements for protection of Highway 37 and Pond 1, including graded intertidal bench in SW corner, earthen viewing pad (Precursor to levee breaches)

Create and enhance upland transition habitat along setback levee and Pond 1 levee

Build Public Access:  fishing pier and kayak launch

Excavate channel for access from kayak launch facility to existing channel

Beneficially reuse up to 405,000 cubic yards of sediment (dredge material) prior to breaching levees to restore up to 50 acres of intertidal habitat

Lower approximately 26,000 linear feet of levee

Breach the Cullinan Ranch perimeter levees at five points and the Pond 3 perimeter levee at three points

Conduct water quality monitoring and habitat monitoring data for methylmercury, waterbirds, vegetation, channel evolution, priority species, sedimentation

Reconnect 1,549 acres of estuarine subtidal and intertidal habitat to San Pablo Bay watershed

Create approximately 30 acres of habitat suitable for Salt Marsh Harvest Mouse (SMHM) colonization

Restore hydrologic connectivity between Cullinan Ranch and surrounding sloughs

Restore hydrologic connectivity with Pond 3

Increase waterbird utilization within 1 year and SMHM utilization within 5 years

Use by target fish species

Improved habitat connectivity among  wetland, transitional and upland habitat

Increased SMHM population size

Ridgway’s rail utilization
Improved water quality with restored tidal marsh

Results will inform future restoration projects and used in adaptive management to ensure project is meeting objectives

Full List of Project Summaries