HONOLULU (HawaiiNewsNow) – A wastewater discharge was reported at Joint Base Pearl Harbor-Hickam following recent heavy rainfall.
JBPHH said the base’s Wastewater Treatment Plant experienced a bypass of the sand filter from 4 p.m. Friday, March 13, through 10:15 a.m. Monday, March 16.
More than five million gallons of partially treated wastewater were discharged through the plant’s offshore outfall into Mamala Bay.
Officials said the wastewater was still disinfected using UV treatment before being released. The outfall extends about 1.5 miles offshore to a diffuser located roughly 150 feet below the ocean surface, where it is mixed with surrounding waters.
According to the Navy, similar past incidents involving UV-treated wastewater have shown bacteria levels remained below permitted limits, with no additional environmental impact.
The treatment plant uses an enhanced secondary treatment system with four steps: clarifiers, activated sludge, sand filtration and UV disinfection. During this bypass, the wastewater skipped the sand filtration step but still underwent UV disinfection before discharge.
The Navy has notified the State Department of Health as required by the WWTP’s operating permit.
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