Spring has sprung, but rivers behaving so far in latest Break-Up Report

The latest NWT Water Monitoring Spring Break-Up Report shows no areas of great concern, but It is important to note that much of the water contributing to NWT rivers originates from outside of the NWT.

The potential and severity of flooding will depend in large part on the weather over the upcoming weeks and how this interacts with existing ice conditions, water levels and snowpack amounts.

As of Monday:

• River ice on the Liard River has broken up. Break-up occurred at Fort Liard on May 2, and advanced downstream. Rubble ice is now moving at the mouth of the Liard River. Levels at the mouth rose 1.3 metres Sunday (within average range). The Fort Liard gauge was lost to ice on May 1. From local reports, both the Liard and Petitot Rivers are flowing well at Fort Liard. Localized jamming reported near the Muskeg River confluence on May 2 has cleared. The Liard River Basin warmed rapidly relative to historical conditions, particularly in the southeast of the basin near Fort Nelson, BC. The rapid rate of warming is expected to slow with temperatures remaining above average this week.
• On the Hay River, ice is primarily melting in place and remains intact but weakening north of the border. The ice front is still south of the NWT border. Water levels are rising gradually on the Hay River at the border, but remain well below average for this time of year. Levels on the Hay River near the Town of Hay River are at a record low for this time of year. In the Hay River Basin, temperatures are forecasted to remain near or slightly above average over the coming week with no significant precipitation events affecting water levels.
• On the Mackenzie River, the ice remains intact downstream of Fort Simpson and upstream at Strong Point, and is degrading thermally. Sections of open water are visible at Mills Lake and near the Strong Point gauge. Above-average temperatures have been experienced over these regions since late April. Above average weather has been experienced in Fort Simpson since April 28. Temperatures are forecasted to remain above average for the upper Mackenzie area. The water level rose 10 centimetres at Fort Providence in the last three days and is now considered average for this time of year.

Great Slave Lake levels have remained relatively stable, rising only about one centimetre over the weekend.