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For Immediate Release
August 4, 2022

Board of Water Supply (BWS) Detects Petroleum
Contamination in BWS Monitoring Well

HONOLULU – The Board of Water Supply has detected polycyclic aromatic hydrocarbons (PAH) in a groundwater monitoring well located in Moanalua Valley.  PAHs are a class of chemicals that occur naturally in coal, crude oil, and gasoline. They also are produced when coal, oil, gas, wood, garbage, and tobacco are burned. High-temperature cooking will form PAHs in meat and in other foods.  BWS also detected total petroleum hydrocarbons (TPH) in the samples tested. The monitoring well, identified as DH-43, is located approximately 1,500 feet to the southeast of the Red Hill facility. The PAHs detected were at very low levels and there is no current change in operations for BWS because of this detection.

“This latest detection of PAH and TPH contamination in DH-43 significantly heightens the BWS’ concern that fuel contamination from the Red Hill facility is travelling through O‘ahu’s sole-source aquifer” said Ernest Lau, Manager and Chief Engineer.  “The recent contaminant detections in our DH-43 monitoring well are warnings that we cannot ignore.  Our precious and irreplaceable water resources are at risk of further contamination every day the fuel remains in the Red Hill tanks. We urge the Navy to expeditiously defuel and permanently close the Red Hill facility – Ola I Ka Wai.”

Since 2014, the BWS has been testing its drinking water wells near Red Hill and the water provided by the BWS to its customers remains safe to drink.  In 2015 BWS also tested DH-43 and found no PAHs or TPH at that time.  In response to the numerous fuel releases from the Red Hill facility and the Joint Base Pearl Harbor Hickam drinking water crisis, the BWS was forced to shut down the operation of its Halawa Shaft, Aiea Wells and Halawa Wells and also increased the testing frequency of its drinking water wells near Red Hill.  BWS also retested DH-43.  The results of the latest PAH and TPH detections in DH-43 are shown on the attached page.

The BWS met with the State of Hawaii Dept of Health (DOH) and the Environmental Protection Agency (EPA) to share the most recent data. Both agencies will be reviewing BWS test results and may also take additional testing samples. However, DOH and EPA agree that at the very low levels detected, it is not expected to cause any health effects; however, while not a current health emergency, it needs attention and continued monitoring.

“We appreciate the Board of Water Supply’s work to fulfill our shared mission to protect public health and the environment. While this datapoint warrants further investigation, more data is needed from BWS’ monitoring wells before we can determine if this detection is related to the Red Hill contamination. We are committed to continued collaboration.

The fuel in the Red Hill tanks continues to pose a threat to our water resources—we need the Navy to feel the same sense of urgency that we do to safely defuel and decommission Red Hill.” -Kathleen Ho, Deputy Director of Environmental Health, Hawaii Department of Health.

“EPA takes this information seriously and is working closely with the BWS and DOH to determine the appropriate next steps to be taken,” said EPA Region 9 Deputy Administrator Deborah Jordan.

For the latest updates from the BWS regarding the ongoing situation at Red Hill and its impact on O‘ahu's precious water resources, go to

About the Board of Water Supply

The Board of Water Supply (BWS), a semi-autonomous agency of the City and County of Honolulu, manages Oahu’s municipal water resources and distribution system.  As the largest water utility in the State, the BWS serves approximately one million customers on Oahu.  The BWS embraces its mission of “Water for Life – Ka Wai Ola” – to provide a safe, dependable, and affordable water supply, now and into the future.  Uwē  ka lani, ola ka honua – “When the heavens weep, the earth lives.”  For more information, visit, follow @BWSHonolulu or like the BWS’s Facebook page at



Kathleen Elliott-Pahinui
Information Officer
Honolulu Board of Water Supply
Phone: (808) 748-5319