The Hilo Wastewater Treatment Plant (WWTP) experienced a break in power service to the Trickling Filter (TF) feed pumps on Thursday, January 27, 2022 from 4:25pm to 4:29pm. The break in power caused wastewater in the TF feed pump wet well to overflow into the effluent channel that feeds the solids contact basin. Approximately 8,600 gallons overflowed during the 4-minute power outage.

At no time did the WWTP disinfection system stop feeding sodium hypochlorite. Treated wastewater discharged into the outfall was processed through the solids contact chamber and secondary clarifiers prior to disinfection and disposal into the outfall. Cause of the Process Bypass: Electric breaker for the feed pump tripped. Remedial Actions Taken: Electrical breaker was resent and faulty feed pump replaced.