THM Water Advisory

CURRENT WATER ADVISORY: THM Advisory Lifted

Latest Updates

Last updated: February 3, 2026

Public Health Advisory Lifted- CPHO

The Office of the Chief Public Health Officer is advising all residents in the community of Hay River, Enterprise, Katlodeeche First Nation and Ka’a’gee Tu First Nation (Kakisa) that the precautionary Public Health Advisory for drinking water has been lifted.

The current annual running average has come below the 100 ug/L threshold and meets the Guidelines for Canadian Drinking Water Quality. Normal use of drinking water may resume. Sample results collected from January 2026 demonstrated improvements with THM levels continuing to drop. The Underground Reservoir sample had a result of 74.2 ug/L. Other test locations were below those concentrations.

The Environmental Health Unit will continue to monitor results from the Town of Hay River water treatment plant and distribution system. The Town will continue to make improvements to the water treatment process and sample results monthly in attempts to further reduce THM concentrations.

The Town, in conjunction with other community governments and partners that are served through the Hay River’s water treatment facilities, will continue to lobby and advocate for a long term solution to replace aging water infrastructure.

Last updated: December 18th, 2025

The Town continues to work closely with the Department of Health and the Department of Municipal and Community Affairs on implementing a strategy to address elevated THM levels. Sample results from the week of December 15th have show improvements with THM levels continuing to drop. The Underground Reservoir sample had a result of 87.5 ug/L down from November’s 98 ug/L result. Other test locations on the distribution system were under 64 ug/L. However, the current locational running annual average remains at 105.75 ug/L (as of November 2025) and as such the THM Advisory remains in place. The next update to the running annual average will occur in January 2026.

November 25th, 2025

The Town of Hay River has been working closely with both the Department of Health and the Department of Municipal and Community Affairs. There have been improvements made to treatment systems, and more optimization processes will be implemented shortly. Recent water sample results have shown improvement in the THM levels, unfortunately, even though this is a good progress, the new annual average is still higher than the Health Canada guidelines values. As such, the Public Health Advisory will remain in effect. The Town will continue to make adjustments to the treatment system and collect new samples for public health review. Current annual sample results are:

28-Jan-25 Underground Reservoir 83 ug/L

29-Apr-25 Underground Reservoir 118 ug/L

19-Aug-25 Underground Reservoir 124 ug/L

18-Nov-25 Underground Reservoir 98 ug/L

November 17th, 2025 – Regular Meeting of Council

The Council of the Town of Hay River accepted a report on the drinking water THM public health advisory. The report provides background on the advisory and information on testing and treatment actions being pursued by the Town and supported by the Chief Public Health Officer. The report can be found on page 58 of the package.

- Water Advisory Report

November 5th, 2025 – Public Meeting

A meeting was held with public officials that included representation from the Town of Hay River, Office of the Chief Public Health Officer, and MACA to present information on the advisory and respond to questions from the public.

- Recorded Water Advisory Public Meeting

November 3rd, 2025 – Public Health Advisory

The Office of the Chief Public Health Officer issued a Public Health Advisory for Hay River, Enterprise, Katl’odeeche First Nation, and Ka’a’gee Tu First Nation (Kakisa) on November 3, 2025 due to elevated Trihalomethanes (THM) levels identified through routine testing.