Drinking Water Advisory for the Hamlet of Fort Liard

NORTHWEST TERRITORIES (December 22, 2025) – The Chief Environmental Health Officer is advising residents of Fort Liard to take simple steps to reduce exposure to Trihalomethanes (THMs) in drinking water.

Recent laboratory-based testing from the Hamlet of Fort Liard, reviewed by the Office of the Chief Public Health Officer, confirms that total THM levels in treated drinking water are above Health Canada’s guideline.

This advisory is precautionary. The health risk is considered minimal, as only long-term (over 70 years) exposure to THMs is expected to cause serious illness.

The main THM found is chloroform. Health effects from chloroform happen at much higher levels above 1,400 micrograms per litre.  THM levels in Fort Liard have likely been higher for some time, but they have never reached the level where chloroform could cause health effects. The average values of total THM for the community are around 139 micrograms per litre.

THMs form when chlorine reacts with natural organic material in water. Factors such as changing climate and water composition cause higher organic materials, and aging infrastructure limits the ability to remove organic materials. Since October 2025, the Hamlet of Fort Liard and Municipal and Community Affairs (MACA) have been implementing short-term measures to reduce THMs, and work continues on a long-term solution.

We will share updates as progress is made.

What residents can do now

  • Use an NSF/ANSI 53 certified water filter that says it removes THMs.  Look for the words “Trihalomethane or THM removal” on the box. Filters can be pour-over, countertop, faucet mount, or under-sink.
    • Why? Filters help lower the level of THMs you drink.
  • Follow the instructions on the filter. Change the filter when the box says to.
    • Why? Old filters stop working and will not remove THMs.
  • If you don’t have a filter, fill a pitcher with tap water and leave it uncovered in the fridge for 24 hours before drinking.
    • Why? Some THMs will leave the water into the air.
  • You can also use bottled water.
  • Do not drink water straight from a lake or river.

Food preparation

  • Use filtered or bottled water for cooking.
  • Tap water can be used to wash fruits and vegetables.
  • When boiling or steaming, ventilate the kitchen to reduce vapour exposure.

Shower, Bath and Housekeeping Use

  • Tap water can be used for brushing teeth, washing hands, and laundry.
  • Keep showers under 10 minutes and baths under 30 minutes. Open a window or use a fan.
    • Why?  A very small amount of THMS can evaporate into the air during bathing. Shorter showers and ventilation help reduce exposure.


More information

 

For media requests, please contact:

Andrew Wind
Manager, Communications
Health and Social Services
HSSMedia@gov.nt.ca