The Board of Water Supply says water is safe to drink for residents along the Waianae Coast after a routine water sample tested positive for E. Coli.

A sample taken Tuesday revealed the presence of E. coli in Kamaile Well Pump #2, which serves the Waianae and Makaha areas from Ala Hema Street up to Keeau Beach Park.

The utility took swift action.

“The minute we find a sample and we determine there is E. coli present, we shut down the well immediately,” said BWS communications officer Kathleen Pahinui.

Before the pump was shut off, “the water is pumped. We add chlorine into the water to disinfect it, then it goes into the water system,” Pahinui explained.

The utility says that disinfection process ensures the water that comes out of the tap is safe to drink.

“The people that receive water from the Board of Water Supply will not see any difference or effect,” Pahinui said.

There are five wells that service the area. Well Pump #2 serves about 1,800 people and pumpes approximately 100,000 gallons of water a day.

An investigation is underway to determine what caused the contamination.

The utility could take the well out of service permanently, or “if we determine that we’re going to keep the well in service, we will use a high level of treatment to remove the bacteria from the water,” Pahinui said.

The U.S. Environmental Protection Agency’s (EPA) Ground Water Rule is a regulatory process aimed to reduce the potential risk of illness caused by microbial contamination in ground water.

Under the Rule, utilities must test their ground water when coliform is detected in any sample collected from the water system.

If E. coli is found in the ground water source, the rule requires the public to be notified.

E. coli detection is not a rule violation, but the rule requires that the public be notified of the finding and that the BWS take corrective actions approved by the State Department of Health (DOH).Here are some frequently asked questions and answers from the BWS:What should I do?

“There is nothing you need to do. This notice is a public announcement required under the drinking water regulations.”What happened?

“On October 24, 2017, BWS detected coliform bacteria in a routine water sample from Keaau Beach Park that was collected on October 23, 2017. In accordance with the Ground Water Rule, BWS staff collected a sample from Kamaile Well Pump #2 on October 24, 2017 which tested E. coli positive the following day, October 25, 2017.

“The BWS immediately collected five (5) additional samples from Kamaile Well, Pump #2 on October 25, 2017 as required by Rule. After the samples were collected the well was then shut down. Two out of the five samples were found to be E. coli positive the following day, October 26, 2017. E. coli testing requires 24 hours to complete.

“The BWS immediately notified the DOH of the finding and is informing the public as required by federal drinking water regulations.

“The water from Kamaile Well Pump #2 is chlorinated before it reaches customers. Samples collected from Keaau Beach Park on October 23 and October 24, 2017 tested positive for chlorine and negative for E. coli. For this reason, the public was not at risk of E. coli exposure.”What is E. coli?

“E. coli bacteria can exist in tropical, sub-tropical, and temperate soil and may persist in soil for a number of years. E. coli is a fecal indicator and microbe whose presence indicates that the water may be contaminated with human or animal wastes. Microbes in these wastes can cause short-term health effects, such as diarrhea, headaches, or other symptoms. They may pose a special health risk for infants, young children, some of the elderly, and people with severely compromised immune systems.”What is being done?

“The BWS, in consultation with DOH, is conducting an investigation to determine the reason for the E. coli presence. Kamaile Well Pump #2 will remain shut down until the BWS concludes its investigation, completes the necessary corrective measures and receives DOH approval to resume well operations.”

For more information, please contact the BWS Water Quality Division at 748-5080 or the EPA Safe Drinking Water Hotline at 1-800-426-4791.