SAN FRANCISCO, California (CNN) -- Nearly 3 million gallons of sewage spilled into San Francisco Bay when a pump failed at a waste treatment facility, the Marin County Sheriff's Department told CNN on Friday. Attempts are being made to contain Thursday night's 2.7 million-gallon sewage spill. The 2.7 million-gallon spill occurred Thursday night. A pump failed at the South Marin Sanitation District's waste treatment facility in the town of Mill Valley, said Lt. Doug Pittman. The waste was released into Richardson Bay, an inlet of the large bay on the east shore of Marin County, he said. See the spill from the air »
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NEW: Sewage was partially treated, Office of Emergency Services says
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The 2.7 million-gallon spill occurred Thursday night, Sheriff's Department says
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Pump and alarm failed at Marin County waste treatment facility
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Area being tested; boaters advised to avoid Richardson Bay area
The accidental release occurred between 5:30 and 8:30 p.m. Thursday, according to a statement from @placeholder's emergency operations center.