Water Quality of the Russian River Watershed After Sonoma and Napa County Fires, Beginning 2017

The Sonoma County Water Agency (SCWA) supplies drinking water to over 600,000 Sonoma County and Marin County, CA residents and relies on a combination of Russian River water and surrounding groundwater. SCWA employs natural removal processes of riverbank filtration (RBF) to provide pretreatment before the river water is chlorinated and distributed in the drinking water system. In addition, SCWA employs an inflatable damn on a seasonal basis to increase water supply at the RBF site. Changes in water quality due to recent and potential future fires within the Russian River water shed could lead to substantial drinking water management challenges. Wildfires can result in water quality impacts including increased loading of sediments, nutrients, dissolved organic carbon, major ions, and metals. It is unknown how these changes in water quality would impact bank filtration efficiency at this site. This data release reports water quality chemistry in the Russian River watershed after the Sonoma and Napa County Fires in October, 2017.