Over the past week the Winnipeg River basin received above normal rainfall and this has caused inflows to both Lake of the Woods and Lac Seul to remain stable and in the high-normal range for this time of year. Lake of the Woods inflow is around 1,700 m3/s (80th percentile) and Lac Seul inflow is around 1,100 m3/s (70th percentile). These inflows have resulted in the continued rise of lake levels, but lake levels and outflows are still within the normal range on both Lake of the Woods and Lac Seul. At Lac Seul, the lake continues to refill with outflows remaining in the normal range.
At Lake of the Woods the current lake level of 323.06 m (1059.91 ft) is 6 cm ( 2 in) above the normal summer level of 323.0 m (1059.7 ft) and 1.06 m (3.47 ft) below the peak level in 2022 of 324.12 m (1063.39 ft). Lake of the Woods outflow is currently 800 m3/s. Lake levels and outflows are being managed in accordance with the regulation strategy adopted in March, taking all interests into consideration both upstream on the lake and downstream on the Winnipeg River. In particular, this consideration from the high inflow scenario applies at this time:
“Avoid outflow above 800 to 900 m³/s if the lake level (or projected level) will remain
below 323.20 m (1060.4 ft) in June. A flow of 900 m³/s on the Winnipeg River would
cause the level below the Norman Dam to rise 1.4 m (4.6 ft) above normal, whereas a
lake level of 323.2 m (1060.4 ft) is only 15 cm (6 in) above median at the end of June.”
Weather forecasts and inflow predictions indicate that the level of Lake of the Woods is not expected to increase above 323.2 m (1060.4 ft) within the next 10 days. Therefore, no additional outflow increases are scheduled at this time. The Secretariat will continue to monitor conditions in the event that inflows remain higher than forecasted.
The current level of Lake of the Woods is 323.06 m (1059.91 ft) , a 60th percentile level, within the normal range for this time of year. The average lake level increased by 13 cm (5 in) over the last week and is expected to increase by 6 to 9 cm (2 to 3.5 in) over the next week, depending on precipitation amounts and upstream flow changes. The current outflow of Lake of the Woods is 800 m3/s. With inflows forecasted to decline with dry weather, no outflow changes are currently planned.
The current level of Lac Seul is 355.72 m (1167.1 ft), a 45th percentile level, within the normal range for this time of year. The average lake level increased by 17 cm (7 in) over the past week and is expected to increase by 12 to 15 cm (5 to 6 in) over the next week. Lac Seul authorized outflow is 300 m3/s with no additional outflow increases currently planned.
If you have any questions, comments or observations, please contact the Secretariat at secretariat@lwcb.ca or by calling 1-800-661-5922. This Noticeboard will be updated regularly as conditions develop.
For more information on Namakan and Rainy Lakes, visit the Water Level Notices page of the International Rainy-Lake of the Woods Watershed Board.
2024.06.06 Conditions Update and Level Forecast – Notice Board (lwcb.ca)