Swimming areas west of Belmont Shore are temporarily closed for water contact because of a sewage spill in San Gabriel, Long Beach City Health Officer Dr. Anissa Davis said Wednesday.

About 15,000 gallons of sewage spilled into Rubio Wash, which leads to the Los Angeles River, according to a report received early Wednesday afternoon from the California Governor’s Office of Emergency Services.

A grease blockage in the San Gabriel sewer main line caused the spill, the report said.

While the origin of the spill is more than 25 miles away, the sewage will eventually make its way to Long Beach shores via the Los Angeles River, Davis said.

State law requires temporary closure and posting at beaches in these situations, out of an abundance of caution, until the water quality meets state requirements, Davis said.

Long Beach Health Department’s Recreational Water Quality health inspection team is monitoring water quality and will do so until results meet the state water quality standards, Davis said.

Beach closures because of upstream sewage spills are common in Long Beach. The city had to close portions of its shoreline at least 63 times over the last five years.

Because most of the spills happen outside of Long Beach, the city is trying to get other cities to do a better job maintaining their sewer infrastructure to avoid having Long Beach residents lose access to their beaches when a spill happens.