NWT Water Monitoring Bulletin – May 12, 2023

News Type: 
Water monitoring bulletin

The Government of the Northwest Territories maintains water monitoring stations across the territory to keep track of water levels and flow rates in areas of potential flood risk for communities.

This information is provided regularly to territorial and regional emergency managers to help understand the status of waterways across the NWT in the lead-up to, and during spring break-up – the highest-risk period for floods in the Northwest Territories.

Technical data

Current status – NWT 

  •  Satellite imagery (from 11 May) and photographs (from morning of 12 May) indicate that break up has progressed down the Mackenzie River past Tulita and is expected to move through Norman Wells today/tomorrow;
    • Ice has started to shift locally at Fort Good Hope, but Mackenzie River ice has not yet pushed past the Ramparts;
  • The water level on the Mackenzie River at Norman Wells has been climbing steadily since 01:30 this morning (12 May);
  • Temperatures in the Sahtu are forecast to be warmer than normal and mostly sunny in the Sahtu through this weekend;
    • Night-time temperatures are forecast to remain above freezing;
    • Ice will continue to degrade and move down the Mackenzie River;
  • Water levels on the Peel and Arctic Red rivers have continued to rise under ice;
    • Temperatures in these basins are expected to be seasonal with intermittent cloud over the next two days, but will rise to well above seasonal and sunny beginning on Sunday;
    • Water levels may rise suddenly as the ice breaks up and snowmelt water moves towards streams and rivers;
    • Current conditions indicate that water levels at break up could approach or exceed the highest level on record and land users should be aware of this;
      • Water levels will vary at different locations and times along the river and will be dependent on how and where ice jams build and release.

Current Status – Mackenzie River

  • Mackenzie River ice has moved past Tulita;
  • The water level on the Mackenzie River at Norman Wells has been increasing steadily since 01:30 this morning;
    • This increase happens every year as the ice front moves through Norman Wells;
    • Water levels are within the range of normal during break up;
  • Ice has shifted locally at Fort Good Hope but the ice front has not moved through the Ramparts as of 11:00 today.

Current Status –Peel River and Beaufort Delta

  • Water levels continue to rise under the ice on the Peel and Arctic Red rivers as snowmelt progresses;
  • Temperatures in Fort McPherson and the Peel River basin are forecast to be seasonal with intermittent cloud cover today and tomorrow, followed by unseasonably warm weather and sun beginning Sunday;
    • This will cause rapid melt of the remaining snowpack;
    • Land users should be aware of the possibility of rapidly rising water levels, especially as ice moves down the Peel and Arctic Red rivers.