The Sonoma Baylands wetland restoration project signaled a turning point in Bay restoration efforts. It was a partnership between industry, government and Bay environmentalists that was designed to resolve an emerging conflict between Bay protection policies and the region’s shipping ports.
One of the most carefully planned wetland restoration projects, Sonoma Baylands was among the first to incorporate the application of dredged bay mud to raise the bottom elevation of the subsided restoration site. Because tidal wetlands throughout the Bay had been surrounded by earthen dikes and drained, they had subsided as much as ten to twelve feet below sea level.
Were breaches to be excavated in the dikes to allow tidewaters to return, the sites would simply become permanent open water, rather than revert to the vegetated tidal marshes that they were before diking. For marsh vegetation to colonize successfully, a minimum bottom elevation must exist on the site.
To solve this problem, Bay mud that was dredged from a channel deepening project at the Port of Oakland was barged to the 360-acre site, and then applied in a slurry. This raised the bottom elevation and allowed the accelerated establishment of marsh plants, such as cordgrass.
New levees were constructed to protect surrounding lands from inundation when the old bayward levees were breached. The slurry pipe was placed atop the new levees. It was extended and moved in order to deliver slurried dredge mud to various location throughout the project site. Construction was completed in 1996 and the project has been monitored closely over the years.
The Bay Institute works to promote regional funding to support this restoration project.