Long Beach shut down its beach swimming areas Thursday night after local health officials learned of a 10,500-gallon sewage spill upstream.

A grease blockage caused the spill in Rowland Heights, which is about 30 miles away from Long Beach, according to the Long Beach Health Department. The sewage ended up in the San Gabriel River and will eventually wash down to Long Beach’s coastline.

Because this week’s rain sent storm drain runoff rushing to the ocean, Long Beach was already advising people to stay out of the water or risk getting sick. The sewage spill escalated that warning to a mandatory closure. City crews were working Friday to post signs at all of Long Beach’s ocean swimming areas.

Locals should be used to this drill by now. With both the Los Angeles River and San Gabriel River ending at its shoreline, upstream sewage spills frequently close local beaches.

Over a recent 5-year span, there were 63 days when upstream sewage spills closed Long Beach’s coastline, leaving city officials searching for ways to hold other cities accountable for the untold economic and environmental damage.

Long Beach’s waterways will reopen when they meet state standards. You can monitor them here.

Jeremiah Dobruck is executive editor of the Long Beach Post where he oversees all day-to-day newsroom operations. In his time working as a journalist in Long Beach, he’s won numerous awards for his investigative reporting and editing. Before coming to the Post in 2018, he wrote for publications including the Press-Telegram, Orange County Register and Los Angeles Times. Reach him at [email protected] or @jeremiahdobruck on Twitter.