Crosses honoring the victims killed in a recent wildfire hang on a fence along the Lahaina Bypass as a Hawaiian flag flutters in the wind in Lahaina, Hawaii, Tuesday, Aug. 22, 2023. Two weeks after the deadliest U.S. wildfire in more than a century swept through the Maui community of Lahaina, authorities say anywhere between 500 and 1,000 people remain unaccounted for. (AP Photo/Jae C. Hong)

The state Department of Health said Thursday that while the initial results of water testing are reassuring, the unsafe water advisories for the Lahaina and upper Kula drinking water systems remain in place.

The initial testing is the first step in a rigorous process to ensure water is safe to resume drinking, the DOH said in a news release. That process may include additional testing, isolating the impacted parts of the system, flushing impacted parts of the system to remove contamination and possibly replacing certain parts of the water distribution system if determined necessary.

The results of the first drinking water tests released by the Maui County Department of Water Supply were collected jointly by Department of Health and Department of Water Supply staff on Aug. 14. Initial testing was for 23 regulated volatile organic compounds listed in the U.S. Environmental Protection Agency drinking water method 524.2. Additional testing may be recommended as work continues.

Twenty-five of the 27 samples from Lahaina and upper Kula did not detect any of the volatile organic compounds. One sample in Lahaina collected from Kaniau Road detected 0.7 parts per billion of benzene, a byproduct of wildfires. The maximum contaminant level allowed in a public water system is 5 parts per billion. Out of an abundance of caution, the Department of Water Supply isolated this part of the system with the hydrant to protect the rest of the system.

A sample collected from the Upper Kula Treatment Plant detected the presence of toluene and xylenes at a level less than 0.5 parts per billion. The maximum contaminant level is 1,000 parts per billion for toluene and 10,000 parts per billion for xylene. The source of the upper Kula system was tested as part of the Health Department’s standard operating procedures. Additional monitoring is underway to ensure that the Upper Kula Treatment Plant continues to meet all primary drinking water standards.

The Upper Kula Treatment Plant is not in an area under the current unsafe water advisory. Based on these results, the Health Department said it does not believe the unsafe water advisory needs to be amended at this time; however, further investigation is ongoing.

Department of Health and Department of Water Supply staff continue to collect water samples from across the Lahaina and upper Kula communities.

“The shared goal is to restore drinking water as soon as we can be certain of its safety and to keep the community informed along the way,” the Health Department said in a news release.