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Notice #: 0001420228-01
Public Notices


Water is safe to drink. The public was never in any danger.

HONOLULU – The Board of Water Supply has detected E. coli bacteria in the raw water before chlorination, from BWS Kahaluu Tunnel.

What should I do?

There is nothing you need to do. Your water continues to be safe to drink. This notice is a public announcement required under Federal and State drinking water regulations.

What Happened?

The Board of Water Supply (BWS) is notifying the public that a water sample taken before chlorination, from BWS Kahaluu Tunnel tested positive for the presence of
E. coli bacteria. As a result, BWS is providing public notice of this finding, as required under the federal Ground Water Rule. The water from this source is safe to drink because it is routinely disinfected with chlorine before it reaches customers. For this reason, no further action is required by customers. Water from Kahaluu Tunnel serves the area from Ahuimanu Road to Likelike Highway.

According to the Environmental Protection Agency (EPA), the Ground Water Rule is a regulatory process aimed to reduce the potential risk of illness caused by microbial contamination in ground water. Under this 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. An E. coli detection is not a rule violation, but the Rule requires that the public be notified of the finding.

On June 15, 2023, BWS detected coliform bacteria in a routine water sample collected June 13, 2023, from the Kaneohe Police Station. In accordance with the Ground Water Rule, on June 15, 2023, BWS staff collected a repeat sample from the Kaneohe Police Station and samples before chlorination from all sources that were serving the Kaneohe Police Station, at Kahaluu Tunnel, Waihee Tunnel, and at all pumps from stations at Punaluu Wells II, Waihee Inclined Wells, Kahaluu Well, Kuou Wells II & III, Kaluanui Wells, and Maakua Well. Of all these pre-chlorination samples, only Kahaluu Tunnel was found E. coli positive the following day, June 16, 2023. The repeat sample from Kaneohe Police Station and samples from all other well pumps and tunnels were E. coli negative.

On June 16, 2023, BWS immediately collected five (5) additional samples before chlorination from Kahaluu Tunnel as required by Rule. After the samples were collected, the tunnel was then shut down because E. coli testing requires at least 18 hours to complete.

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 a 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.

The BWS notified the State Department of Health (DOH) of the finding and is informing the public as required by Federal and State drinking water regulations.

During the time Kahaluu Tunnel was operating, chlorine was continuously being added to the water before it reaches customers. Water samples collected from the Kaneohe Police Station on June 13 and 15, 2023 had chlorine present and tested negative for E. coli. Samples also collected on June 13, 2023, from Heeia Neighborhood Park and on June 15 from Heeia Neighborhood Park, Kaneohe Civic Center Neighborhood Park, and Ben Parker Elementary also had chlorine present and tested negative for E. coli. Because chlorine is continuously being added to the water from Kahaluu Tunnel before it reaches customers, the public is not at risk of E. coli exposure.

What is being done?

The BWS, in consultation with DOH, is investigating to determine the reason for the E. coli presence. Kahaluu Tunnel will remain shut down until the BWS concludes its investigation, completes any necessary corrective measures, and receives DOH approval to resume tunnel operations.

The BWS will issue a second notification on June 17, 2023, with the results of the additional five (5) samples from Kahaluu Tunnel.

For more information, please contact the BWS Water Quality Division at (808)
748-5841 or the EPA Safe Drinking Water Hotline at 1(800) 426-4791.

Please share this information with all the other people who drink this water, especially those who may not have received this notice directly, for example people in apartments, nursing homes, schools and businesses. You can do this by posting this notice in a public place or distributing copies by hand or mail.
(SA1420228 6/25/23)