We provide water level and flow outlooks so communities have information on water conditions on the Churchill, Nelson, and Burntwood rivers during the spring melt.*
Churchill River (Southern Indian Lake to Hudson Bay)
Spring melt started in May with flows lower than last year but above average.
The upper portion of the Churchill River watershed received above average snowpack while the lower portion near the river mouth has average snowpack. Current inflows from Saskatchewan to Southern Indian Lake are about 53,000 cubic feet per second (cfs) (1,495.93 cubic metres per second (cms)) and have started to rise from spring melt. The level of Southern Indian Lake is higher than normal for this time of year at 845.8 ft (257.79 m) and is expected to begin increasing shortly. Outflows through Missi Control Structure have gradually been increasing and reached around 15,001 cfs (424 cms) today and will be increasing gradually over the next few weeks to make room for spring meltwater and reduce the need for higher flows later on. River flows are above average for this time of year.
Much of the Churchill River flow is diverted out of Southern Indian Lake through the Churchill River Diversion via the Notigi Control Structure to the Rat and Burntwood rivers. Flows through Notigi are 28,000 cfs (796.22 cms) to reduce flows on the Burntwood River and into Split Lake during the spring melt.
Nelson River flows will rapidly rise over the next few weeks.
Recent heavy precipitation across southern Manitoba is flowing into Lake Winnipeg and downstream through the Nelson River. Lake Winnipeg water level is expected to exceed 217.93 metres (715 feet) in the coming days, requiring Manitoba Hydro to operate at maximum discharge. Jenpeg outflows are being increased to accommodate this water. Jenpeg flows are at around 92,000 cfs (2,600 cms) and will be increased by 5,000 cfs( 140 cms) daily until Lake Winnipeg discharge is maximized; Kelsey flows are at 88,000 cfs (2,500 cms) and will rise together with Jenpeg outflows. Split Lake water level, currently at 550.1 ft (167.28 m), is expected to rise about 1.3 ft through May to elevation 551.4 ft (168.07 m) – this forecasted level is still within the normal high range and is about 4 ft lower than the Spring flood level in 2017. Additional rise is forecasted in June and July.
*Spring flows depend on how long it takes for snow to melt (i.e. warm temperatures will cause a fast melt and higher water flows; while cooler temperatures will cause a slow melt and moderate flows for a longer period of time). Conditions can also change rapidly if a large rainfall or snowfall event occurs. Outlook information will be updated as conditions change.
The Outlook is based on a combination of current and forecasted weather data from Environment and Climate Change Canada; recent and historic streamflow conditions based on both federal and Manitoba Hydro data; Manitoba Hydro regulation models for Reindeer Lake and Southern Indian Lake; snow surveys conducted by Manitoba Hydro; and snowpack estimates from satellite data.
If you have any questions or concerns, please contact:
Waterway Community Engagement