Approximately 1,548 gallons of partially treated wastewater were discharged from the Wahiawa Wastewater Treatment plant into Lake Wilson on Sunday, according to the state Department of Health’s Clean Water Branch.

Due to a power flicker, the wastewater did not receive normal UV treatment before it entered the reservoir downstream of the plant.

Signs will be posted and water samples will be tested at first light on Monday.

The department is advising the public to stay out of Lake Wilson until the warning signs are removed.