Construction of the Bayfront Canal & Atherton Channel Flood Protection and Ecosystem Restoration Project concluded in January 2022, bringing over a decade’s worth of planning to a conclusion.
The Bayfront Canal and Atherton Channel watersheds drain a predominantly urban, low-elevation area in San Mateo County, collecting stormwater runoff from the municipalities of Redwood City, Menlo Park, Atherton, and Woodside, and unincorporated San Mateo County. Just east of Highway 101 and north of Marsh Road, the Atherton Channel converges with the Bayfront Canal near the border between Redwood City and Menlo Park, and empties into San Francisco Bay through a tide control structure not far from Bedwell Bayfront Park. For the past several decades, high tides have kept flows in the Canal and Channel from draining to the Bay, when even minor rainfall events have resulted in the flooding of nearby mobile home parks and businesses; these properties have experienced flooding 40 times over the past 70 years – most recently in 2017.
In response to this proven threat, in October of 2017, Redwood City, Menlo Park, Atherton, and the County entered into an MOU that established shared funding responsibilities for the design, environmental documentation, and land access agreements of a project to reduce the frequency and impacts of flooding. When the District was established in January 2020 it assumed the lead role to complete this Project, with the above Cities and County as continued partners on the Project.
The Project consists of two parallel underground culverts that divert excess flow from Atherton Channel and Bayfront Canal into managed ponds within the Ravenswood Complex of the South Bay Salt Pond Restoration Project. The Project features will be within and along Bayfront Canal, Flood Slough, the entrance to Bedwell Bayfront Park, and the managed ponds owned by the U.S. Fish and Wildlife Service. The successful implementation of this Project will protect developed areas of Redwood City, Menlo Park, and unincorporated San Mateo County against frequent flood events, provide water quality and ecosystem benefits to the managed ponds, and complement existing and future flood protection efforts upstream along Atherton Channel.