UPDATED at 6:00 p.m., Tuesday, September 15: The spill was worse than first reported.

L.A. woke up this morning to a downpour. As urban runoff gets flushed into the sea, it's a good idea to avoid the beach for a few days. The situation is particularly grim in Long Beach, where several hundred thousand gallons of raw sewage flowed into the L.A. River and then into the ocean.

According to officials at L.A. County Sanitation Districts, the spill happened near Commercial Avenue in San Gabriel, where a 24-inch sewage pipe passes underneath the Rubio Wash. Construction crews have been doing work on the pipe as part of the Alameda Corridor East freight train project.

The sewage line was left temporarily exposed, said Steve Highter, a spokesman for the sanitation districts. Sometime before 7 a.m. this morning, the construction site was overrun with storm water, and the sewage spilled into the wash. From there, it traveled to the Rio Hondo, then into the L.A. River, and finally into the ocean at Long Beach, 33 miles from the original spill.

Highter said crews were able to divert the flow of sewage to other pipes, ending the spill sometime before 1 p.m. But by then, Long Beach officials estimate that some 250,000 gallons had flowed into the ocean.

Long Beach public health officials have ordered the closure of beaches in the area. No word on whether it's still OK to kayak in the L.A. River, but we'd probably avoid that too.

Elsewhere around L.A. County, the storm flushed a lot of plastic bottles, food packaging and other trash out onto beaches.

UPDATED at 6:00 p.m., Tuesday, September 15: Long Beach health officials now estimate that 420,000 gallons of raw sewage spilled into the ocean.

“It's a lot,” said Nelson Kerr, manager in the city's Bureau of Environmental Health. “If you came down here, you'd see a lot of debris in the water. It kind of mixes in.”

The beach closure will last at least through Friday, and possibly Saturday, Kerr said. Beaches in the adjacent communities of San Pedro and Seal Beach have not been closed, as current patterns and distance make it less likely that they will be affected.

First posted at 3 p.m. With reporting by City News Service.

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