Russian River Inflatable Rubber Dam Going Up

The Sonoma County Water Agency (Sonoma Water) began inflating its rubber dam on the Russian River near Forestville on Monday, May 6, 2019. The rubber dam is a critical component of the Russian River water supply system that provides naturally filtered drinking water to more than 600,000 residents in portions of Sonoma and Marin counties.  The rubber dam will remain inflated through summer and into the fall.

The rubber dam is typically inflated in spring when demand for potable water increases. When fully inflated, the rubber dam creates a small pool of water from which Sonoma Water draws water for use in four off-stream infiltration ponds. The infiltration ponds help recharge groundwater which is then naturally filtered through sand and gravel and delivered to Sonoma Water’s customers.

Boaters must portage around the rubber dam, located downstream of Wohler Bridge. Public notices will be posted around the rubber dam warning the public not to recreate on or near the dam. California Department of Fish and Wildlife regulations prohibit fishing within 250 feet of the upstream and downstream sides of the rubber dam.

The Russian River Biological Opinion, issued in 2008 by National Marine Fisheries Service, found that fish screens at Sonoma Water’s River Diversion Structure could harm small fish, including young endangered Coho salmon and threatened steelhead. In order to comply with the Biological Opinion and continue operating its system, Sonoma Water in 2016 installed a new, improved fish screen. In conjunction with the installation of the fish screen, Sonoma Water also constructed an improved fish ladder and viewing gallery. The new fish ladder creates better conditions for adult and juvenile salmon moving up or downstream, and allows more native species to use the ladder for migration.

For more information about the rubber dam and how the Sonoma Water delivers naturally filtered Russian River water to its customers, please visit www.sonomawater.org/water-supply .