Officials said on Monday that about 75,000 gallons of sewage overflowed into the Montecito and Happy Valley communities in San Rafael after the pipeline was blocked.

A leak occurred near Highland Avenue above San Rafael High School last week. According to the California Regional Water Quality Control Board, this is the latest sewage spill and is believed to be related to the atmospheric river storm that hit the Bay Area on October 24.

Doris Toy, the regional manager of the San Rafael Health District, said that there were no blockages or leaks for about two weeks before the report and removal on Thursday. She said the pipeline was filled with gravel and rocks.

The staff who responded on Thursday disinfected the surrounding area and launched an investigation to determine whether the sewage flows into the San Rafael River and eventually into the San Francisco Bay.

Greg Piri, the interim director of the Marin County Environmental Sanitation Services, said that experts believe that sewage flows into the canal pumping station through the rainwater system. He said the water was diverted from the pumping station to a nearby sewer system.

"There are currently no major health issues," Pirie said.

Toy said that many spring water and bay water were diluted by waste water.

"We are conducting tests every day to confirm that there are no health threats," she said.

As a precautionary measure, signs warning of possible contamination are still posted on the Municipal Yacht Harbor behind the Montecito Plaza Shopping Center, San Rafael Yacht Harbour near Francisco Boulevard East, and Lowrie Yacht Harbor near Point San Pedro Road.

Toy said the agency is testing enterococci and fecal coliforms in the area. The test usually takes three to four days to get results. The results will be submitted to the Environmental Sanitation Department of Marin County for review.

District law enforcement officer Bill Johnson said that the certification report of the incident will be submitted to the Water Quality Commission within 45 days.

Johnson said that the October 24 storm caused widespread problems. According to a report by Johnson, Sausalito reported 82,500 gallons of sewage overflow, and the Point Isabel wet weather facility in the East Bay Municipal Utility District discharged approximately 3 million gallons of fully chlorinated wastewater.

The report said that South San Francisco, Burlingame, Millbrae, San Mateo and Richmond also reported similar leaks.

"This is not surprising, because in many areas, aging infrastructure allows rainwater to enter the sewer collection system through inflow (e.g. manholes) and infiltration (through pipe cracks) during heavy rains and high flows that may exceed the system capacity, especially when blocked There may be contraction under the circumstances," Johnson wrote.

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