Notification of elevated bacterial level shown in single sample of treated effluent taken at Kailua Regional WWTP

HONOLULU - The Kailua Regional Wastewater Treatment Plant (WWTP) operates under the terms of a National Pollutant Discharge Elimination System (NPDES) permit issued by the Department of Health, state of Hawaiʻi (DOH), which allows the city to discharge treated effluent through a deep ocean outfall located approximately 5,000 feet from the shoreline at a depth of 105 feet below the surface of the water.

One of the many parameters that the city monitors for in its treated effluent is enterococcus, which is a bacteria that is naturally present in Oahu's soils and also enters the ocean water naturally via e.g. storm runoff from rainfall events. The city monitors enterococcus by means of a single grab sample taken at a specified point within the treatment plant, after treatment but before discharge through the outfall.

A single sample collected April 27 at 8:03 a.m., and April 28 at 1:35 p.m., displayed elevated level of enterococcus. A single sample taken April 26, was within normal ranges. The city will continue to collect additional daily samples of the effluent.

The city will also continue collecting daily samples at the shoreline stations. Signs are posted to stay out of waters around the outfall. The city will conduct monitoring at the monitoring stations around the outfall when ocean conditions are safe enough to do so.

The city will provide this notification based on the results of its additional testing.