Hundreds of thousands of gallons of partially treated sewage spilled into the Russian River County Sanitation District Treatment Plant property last Friday as a storm rolled through the area and knocked out power for a few hours. 

Starting late Friday night and continuing into the early morning hours of Saturday, the power outage combined with a large influx of stormwater into the treatment plant to produce a 277,000-gallon spill of “secondary treated wastewater,” according to officials with Sonoma Water, which owns and operates the plant.

While most of the spill was confined to the plant, which serves the communities of Guerneville and Monte Rio, some of the effluent washed through a wooded area and into the Russian River, which is about a third of a mile away. 

Sonoma Water officials said Thursday that they sent environmental specialists to the area who found no impacts to land or river creatures.

“Secondary treated effluent has had the large, inorganic material removed, and much of the organic material has been biologically neutralized,” Sonoma Water officials said. “Secondary effluent has flowed through clarifiers to remove solids, but some suspended solids can remain that would be removed in the third, and final stage of the wastewater treatment process.”

The Russian River County Sanitation District serves the equivalent of 3,214 single-family homes in the region.

Kiley Russell writes primarily for Local News Matters on issues related to equity and the environment. A Bay Area native, he has lived most of his life in Oakland. He studied journalism at San Francisco State University, worked for the Associated Press and the former Contra Costa Times, among other outlets. He has covered everything from state legislatures, local governments, federal and state courts, crime, growth and development, political campaigns of various stripes, wildfires and the aftermath of Hurricane Katrina.