A private homeowner in the San Geronimo Valley is collaborating with the Marin Resource Conservation District in an unprecedented effort to rejuvenate fish habitat in a residential area along San Geronimo Creek. The project is the first of its kind to come out of the landowner assistance program and is primarily funded through a $200,000 grant from the California Coastal Conservancy, awarded earlier this month. Eroded streambeds and banks have been detrimental to the spawning and rearing of critical coho salmon. The goal is to anchor logs, tree roots and boulders into a 370-foot section of creek to create deep cool-water pools that provide refuge during strong stormwater flows and improve the survival of young fish. The project will dewater a section of the creek with a temporary dam—a bypass will allow water to reroute around the site—to allow workers to build up creek banks with boulders and 18 pieces of wood. The grant will cover several permits required by state and local agencies, and the review under the California Environmental Quality Act will be streamlined through Marin RCD’s coordination program. Sarah Phillips, the R.C.D.’s urban streams program manager, said the effort was born out of a 2008 analysis by the county Department of Public Works that observed limiting factors for attracting salmon in the Lagunitas watershed. Forty residents initially applied to the landowner assistance program, but technical issues and location needs reduced the number down to 10. Three locations—in Lagunitas, San Geronimo and Woodacre—were selected as pilot projects, and Ms. Phillips began writing grant proposals. The Coastal Conservancy has worked with local nonprofits to restore habitat for salmon in West Marin for years, including the large-scale tidal marsh restoration at the Giacomini wetlands. Joel Gerwein, a project manager for the conservancy, said they often work with the R.C.D. because of its effectiveness. “Their ability to facilitate environmentally beneficial projects on private and often working lands is amazing,” he said. “Few organizations are more effective than the Marin R.C.D.” The first of the three projects will begin in summer 2019, and a grant from the California Department of Fish and Wildlife will help fund work on the second location. “The coho are dancing!” Ms. Phillips said.