GUERNEVILLE, Calif.—The Russian River County Sanitation District Treatment Plant experienced a spill of secondary treated wastewater, according to a press release by Sonoma Water.
The spill occurred in California’s Sonoma County on March 1 and continued into the morning of March 2. The spill is believed to have been caused by the weekend storm in progress at the time.
It is estimated that nearly 277,000 gallons of secondary treated wastewater spilled on the treatment plant property.
The spill occurred after a power failure shut the facility down, Assistant Sonoma Water General Manager Pam Jeane told The Press Democrat.
She said when power was restored, a programmable controller reset valves in the system, closing off access to the third treatment step and allowing flows to build up between the second and third treatment phases until the basin overflowed.
Part of the spill remained onsite at the treatment plant on Neeley Road in Guerneville, California, but according to the press release an unknown portion of the spill traveled a third of a mile through a forested area and leaked into the Russian River.
The land is so “wet and boggy” that it’s impossible to determine how much effluent stayed on land or got into the river, Ms. Jeane told The Press Democrat.
Due to the storm, the Russian River rose overnight, and at the time of the spill the flow of the river was approximately 7,500 cubic feet per second, which is over 3.3 million gallons per minute, at the Hacienda Bridge in Forestville.
“Any spill would have diluted very rapidly,” Ms. Jeane told The Press Democrat. “It’s still not OK.”
The programming glitch that caused the valves to reset has been fixed, she said.
The storm delivered more than 2.5 inches of rain to the Guerneville area from Feb. 29 to March 2, and it cut power to tens of thousands of residents across the region, according to the Press Democrat.
Sonoma Water said staff notified the proper regulatory agencies, and environmental specialists were dispatched to the site; no effect on aquatic or terrestrial life has been observed so far.
The regulatory agencies that were notified include the North Coast Regional Water Quality Control Board, the California Department of Fish and Wildlife, the National Marine Fisheries Service, and the U.S. Army Corps of Engineers, according to the Press Democrat.
According to the press release, secondary treated sewage has had the large inorganic material removed, and much of the organic material has been biologically neutralized. Secondary sewage 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 began operations in 1983. It serves the equivalent of 3,214 single-family dwellings within a 2,700-acre service area from Rio Nido to Monte Rio.
The sanitation facility has a design capacity of 710,000 gallons per day in average daily dry weather flow.
Discharge of treated water from the facility is between Oct. 1 and May 14, into the Russian River. Between May 15 and Sept. 30, the treated water is used for irrigation on forested land adjacent to the treatment plant and on the Northwood Golf Course nearby.
The Epoch Times reached out to Sonoma Water for comment but did not hear back by press time.
