Last week’s forecasts from various weather agencies overestimated precipitation over the past weekend. For headwater areas to Lake of the Woods, including La la Croix and Seine River, the smaller rainfall totals have allowed for high river levels to peak and start receding.
These high flows have led operators at dams at Rainy Lake and Namakan Lake to ramp up outflow to high spring levels in compliance with directives from the International Joint Commission’s Water Levels Committee. The Lake of the Woods Control Board has no authority over these flows, but is in close communication with this committee and is adjusting outflow from Lake of the Woods proactively in response to upstream conditions. Lake of the Woods outflow was increased from 475 to 550 m³/s on Tuesday, May 19. No further flow changes are currently scheduled. Should wet weather return, further increases are possible.
The current level of Lake of the Woods is 322.79 m (1059.0 ft), the median or 50th percentile level for this time of year. The average lake level rose by 6 cm (about 2.5 in) over the past week, and is expected to rise by 4-6 cm (about 2-2.5 in) over the next week. The level of the Winnipeg River between Kenora and Whitedog is not expected to change over the next week.
At Lac Seul, inflows from Lake St. Joseph continue to rise with the tail end of snowmelt happening in that basin. Very high flows from tributary rivers to Lac Seul near Sioux Lookout, the English River and the Sturgeon River, have peaked and should begin to drop with the drier forecast. Inflow to Lac Seul will remain seasonally high this month, regardless of additional rain amounts.
The current level of Lac Seul is 355.47 m, 1166.2 ft, which is 60th percentile for this time of year. The lake level increased by 20 cm (8 in) over the past week and is expected to rise by a similar amount over the next week. Lac Seul authorized outflow will be increased from 350 to 400 m³/s on Thursday May 21.
A number of website visitors have reported issues accessing up-to-date graphs and reports on the Basin Data page using Android devices. To address this issue, the Secretariat has updated links to these graphs and reports. All links to products as listed on the Basin Data page are correct, but those accessing individual graphs and reports using bookmarks will need to update their bookmarks to open the latest graphs going forward.