Elevated counts of bacteria have been found in samples of treated effluent taken at the Kailua Regional Wastewater Treatment Plant after sequential storm events with heavy rainfall.

The city’s department of Environmental Services announced Sunday that single samples, taken on Friday at 10:13 a.m., and Saturday at 8:28 a.m., showed a enterococcus level that was higher than the limit in the National Pollutant Discharge Elimination System (NPDES) permit.

The state Department of Health issued a brown water advisory for Oahu on Thursday, which remains in effect, and advises the public to stay out of flood waters and storm water runoff.

Signs now are posted to stay out of the waters around the ocean outfall where waste is discharged approximately 5,000 feet from the shoreline at a depth of 105 feet below the surface. The advisories will be removed once enterococcus levels are within the permit limit.

Rainfall from the recent Kona low event resulted in the high flows, which are believed to be the cause of the increased bacteria at the treatment plant.The city is using the Kaneohe-Kailua underground sewer tunnel to regulate flow into the plant.