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San Francisco Bay Delta

San Pablo Bay Tidal Marsh Enhancement and Water Quality Improvement Project

This project will enhance approximately 300 acres of tidal marsh in Sonoma Creek marsh by excavating a new channel. Material from the excavation will be used to create new transitional ecotone habitat and the improved tidal exchange will improve water quality by reducing the need for application of pesticides to control mosquitoes.

Project Facts

Recipient: Audubon California
Funding: $235,884 (non-federal match = $78,620/leverage = $1,060,500)
Project Period: August 2012 – December 2014
Partners: US FWS, Wildlife Conservation Board, Marin Sonoma Mosquito Vector Control District, STRAW, San Pablo Bay National Wildlife Refuge (SPBNWR)

Environmental Results Summary: San Pablo Bay Tidal Marsh Enhancement and Water Quality Improvement Project

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

OUTCOMES (Environmental results)

(1-5 yrs)


Excavate a large tidal channel through the center of the marsh and small lateral channels from the newly excavated large channel

Expand the size of some existing small channels connecting to and within the relic berm area

Construct several small high tide refugia within the marsh interior alongside and near the newly excavated channel, using sediments excavated from the new channel

Construct wetland transition ramps along the upland edge of the marsh, using sediments excavated from the new channel

Revegetate the refugia berms and wetland-transition ramp with appropriate
native vegetation

All involved in hundred and 54 Conduct baseline and post construction monitoring of physical and biological conditions

Improve water quality by reducing the annual application of pesticides (pounds per acre of active ingredient) by 75% within two years and by improving the filtering capacity of the tidal marsh

Tidal circulation and drainage will improve the ecological function of 300 acres of tidal marsh

Acres of water impounded will be reduced by 75% within 2-3 years

Mosquito populations will decline with improved tidal circulation within two years

Benefits to estuarine-dependent wildlife. Abundance of SMHM, CLRA, California Black Rail, and San Pablo Song Sparrows within the impounded areas will remain stable or increase within the project area three to five years after construction

Create, restore and enhance 164 acres of wetlands and habitat at Breuner Marsh along the Point Pinole Regional Shoreline in Richmond

Full List of Project Summaries