Great Slave Lake water level ‘slowly rising’

The latest Northwest Territories water level data suggests signs of a recovery in some places, though how the spring melt will affect things remains a major unknown.

In a report circulated this week, the Department of Environment and Climate Change said Great Slave Lake’s water level has been “slowly rising since mid-December” and is now about 20 cm higher than at this time last year, which was the lowest on record.

Large areas of the territory have been in drought since 2022.

The Slave River is an example of a river that seems to be staging a comeback.

That river is “nearly within the average range for this time of year,” the department wrote in its report. The Slave is reported to have risen by about two metres between February 2024 and February 2025.

However, flow rates on the Hay River remain well below average for the time of year, while Great Bear Lake is at its lowest February water level on record.

Water levels are still noticeably low on the Liard River and at multiple points along the all-important Mackenzie River.

Whether that will remain the case in the summer, disrupting another barge resupply season along the Mackenzie, is unclear.

The spring melt involves multiple factors like how much snow fell, how the snow melts and how much precipitation happens between now and then, all of which make this an early point at which to draw conclusions.

“January precipitation across the NWT was generally below average, except Norman Wells and Inuvik, which received average and well above average precipitation, respectively,” ECC’s report stated.

Temperatures in January were much warmer than average for all communities.

“Water levels on Great Slave Lake and the Mackenzie River are strongly influenced by precipitation received in northern British Columbia, Alberta, Saskatchewan, and southern NWT,” ECC stated.

“Precipitation in the Great Slave Lake basin in northern British Columbia and Alberta has been approximately average this winter.”

Forecasts for the next three months “indicate near-normal precipitation for most of the NWT and the Mackenzie River basin,” the report added, while “below-average precipitation is forecast for February in the southwest areas of the NWT.”