About 21,000 gallons of raw sewage flowed into Waimano Stream before city workers could bypass a break in a 10-inch pipe at the Pacific Palisades Wastewater Pump Station on Thursday afternoon, according to a press release from the mayor’s office.

The stream flows into Pearl Harbor.

“An operator noticed the break around noon,” the release stated. “Crews worked to install a bypass around the spill area,” completing the work about 3:30 p.m.

The city notified the state Health Department, and workers were posting warning signs and taking water samples.

“People are encouraged to stay out of the affected waters until signs have been taken down,” the release stated.

The pump station is located at 1810 Komo Mai Drive.