SEAL BEACH – About 1,000 feet of beach, from the San Gabriel River to around Third Street, was closed Monday because of a sewage spill that began in La Mirada and eventually made its way into the ocean, an Orange County health official said.

The earliest that portion of the beach can open is Wednesday, said Anthony Martinez, a water quality program manager for the Orange County Health Care Agency.

Around 1 p.m. Saturday, a sewage pump station in La Mirada in Los Angeles County lost power, Martinez said. About 3,000 gallons of sewage seeped out; about half of that streamed across a parking lot and ended up in Coyote Creek near Behringer Park.

The creek runs through several Orange County cities before dumping into the San Gabriel River, which flows into the Pacific Ocean at Seal Beach.

The Health Care Agency heard about the spill from L.A. County around 7 p.m. Saturday and closed the 1,000 feet closest to the river.

“Part of the reason it’s such a small area is that the sewage had to travel such a long way,” Martinez said. “The sewage got diluted by the water.”

The agency tested the water on Monday and will do so again Tuesday. If the bacteria is at acceptable levels both of those days, then that portion of beach would re-open Wednesday, Martinez said. The bacteria must be at acceptable levels for two consecutive days before the Seal Beach waters are deemed safe.

The Los Angeles County Public Works Department, which provides services to La Mirada, repaired the pump and cleaned up what it could, Martinez said.

But once the sewage makes it into a waterway, there is not much officials can do to remove it, he added. Sunlight, though, helps breakdown the bacteria and the conditions in the San Gabriel River will also help kill off bacteria; those reasons, as well as dilution, means it’s only a matter of time before the water is safe again, Martinez said.

During the beach closure, the affected area is closed to swimming, surfing and diving.

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