City beaches were ordered closed this afternoon after 250,000 gallons of sewage spilled into the city of San Gabriel’s storm system Tuesday morning—about 33 miles upstream from Long Beach—city health officials announced.

The spill happened at 7:00AM on Tuesday, September 15, off of Commercial Avenue in San Gabriel in connection with the ongoing Alameda Corridor-East rail project, according to Los Angeles County Sanitation District spokesman Steven Highter. The sanitation district is focusing on mitigating traffic congestion at rail-roadway crossings in the San Gabriel Valley.

According to Highter, workers were lowering a storm drain at the project site, where an existing sewer was exposed.

Due to heavy rain, water from the nearby Rubio Wash channel spilled onto and caved through the construction area, damaging and overflowing the sewer, Highter said.

Highter confirmed that as of 1:00PM, ACE Construction Authority crews stopped the spill by diverting the flow to a smaller, nearby sewer.

As a precaution, Long Beach Health Officer Dr. Mitchell Kushner ordered all swimming areas in the city’s open coastal beaches closed until lab results confirm that water is safe for swimming.

Kushner also issued a rain advisory for all recreational beaches and bays in the city, following the rain experienced in the last 24 hours, according to a press release.

“After any significant rainfall, unhealthy conditions may result from increased runoff from storm drain outlets and rivers, which eventually reach the City’s beaches,” the release stated.” “Recreational swimming areas should be avoided for three days following the end of a rainstorm.”

For the latest status on Long Beach recreational beach water quality, call the Water Hotline at 562.570.4199 or visit www.longbeach.gov/health/eh/water.

This story was update at 3:20PM with information on the cause of the sewage spill and a rain advisory.