Sonoma Water raises Russian River dam to shore up summer drinking water supply

It’s the time of year, when a massive 100-foot rubber dam emerges from the bottom of the Russian River near Forestville. That’s to ensure the 600,000 residents of Sonoma and Marin counties who rely on the river for drinking water have a stable supply during summer, when demand for water increases but river levels are lower. 

Monday marked the start of the three-day process of raising the dam, which was first raised in the 1970s. Throughout the year, six caissons — or wells — dig 100-180 feet beneath the riverbed to draw up water, which is filtered by gravel along the bottom of the waterway.