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San Francisco Bay Delta

Emerson Parcel of Dutch Slough Tidal Marsh Restoration Project

The California State Coastal Conservancy has been planning tidal marsh restoration at Dutch Slough, an area of 1,178 acres of diked lands, since 2002.  This project will fund restoration of Dutch Slough’s Emerson Parcel which will restore 240 acres of tidal marsh, 15 acres of riparian woodland and scrub, and 100 acres of open subtidal waters.  Restoration activities include grading for tidal marsh elevations, levee breaching, construction of water control structures, and re-routing Marsh Creek to restore the creek delta on the Emerson parcel, providing seasonal freshwater flow cues to out-migrating salmon.

Project Facts

Recipient: California State Coastal Conservancy
Funding: $1,400,000 (non-federal match = $2,754,000), FFY: 2011
Project Period: Project Period: September 2011 – September 2018
Partners: US Fish and Wildlife Service, CA Department of Water Resources, Reclamation District 2137, CA Department of Fish and Wildlife

Environmental Results Summary: Emerson Parcel of Dutch Slough Tidal Marsh Restoration Project

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

OUTCOMES (Environmental results)

(1-5 yrs)


Eliminate cattle grazing on 425 acres

Conduct pre-project water quality monitoring

Grade marsh plain and Marsh Creek channel

Construct water control structures

Revegetate the marsh

Pre-breach revegetation of 15 acres of riparian woodland and scrub

Reestablish Marsh Creek Delta and hydrologic processes by routing Marsh Creek through the Emerson parcel. New delta will replace straightened, channelized stream bed (approximately 1.25 miles) with sinuous dendritic channels (approximately 2.5 miles).

Breach levees to reintroduce tidal action and reestablish a supply of natural freshwater flows and fluvial sediments to approximately 240 acres

Contribute to scientific understanding of ecological restoration by implementing the project under an adaptive management framework

Design and construct the project with minimal high marsh habitat, because these areas, with frequent wetting and drying, can be sources for mercury methylation

Filter pollutants from terrestrial runoff and improve water quality

Create freshwater signal to attract native fishes to spawning/rearing habitats

Contribute to primary productivity and enhance food supply for sensitive pelagic species potentially including Delta smelt and longfin smelt through export of nutrients

Increase habitat for sensitive native species (Chinook salmon, Sacramento splittail, California Black Rail,  Swainson’s Hawk, Loggerhead Shrike,  Tricolored blackbird) and potentially spawning habitat for Delta smelt

Minimize production and export of methyl mercury

Restore tidal channels (> 5 miles)

Restore approximately 240 acres of freshwater intertidal marsh

Restore 15 acres of riparian woodland and scrub-shrub

Restore approximately 2 miles of shaded riverine aquatic habitat

Preserve and enhance up to 100 acres of managed freshwater marsh

Full List of Project Summaries