About 9,500 gallons flowed into Mamala Bay after a pump failure, the military said.

The wastewater treatment plant at Joint Base Pearl Harbor-Hickam released approximately 9,500 gallons of partially treated wastewater into Mamala Bay after a failure in the four-step treatment process, the military said Monday.

A pump failure caused the water to bypass the sand filter stage on Sunday and poured into the bay, which is near the entrance channel to Pearl Harbor, through the plant’s outfall, according to a press release.

The base said the flow of water stretched into a 150-foot-deep diffuser where it was mixed with water from ocean currents.

“The partially treated wastewater was discharged a mile and a half from the shore, therefore, there should be no impact to beaches or nearshore waters along the Joint Base Pearl Harbor-Hickam shoreline,” said the base commander, Capt. Mark Sohaney.

The four-step process at the wastewater treatment plant usually includes clarifiers, an activated sludge process, sand filtration and ultraviolet disinfection. The partially treated wastewater skipped the third step but was disinfected through the ultraviolet disinfection system, the military said.

The Navy has notified the State Department of Health about the issue.

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