Level Forecast
While Lake of the Woods has returned to the legislated operating range, it remains almost 30 cm (1 ft) above normal summer targets, while the Winnipeg River near Kenora is over 180 cm (6 ft) above normal summer levels. The Board has begun a series of regular outflow reductions from Lake of the Woods to target low-normal levels by the end of October for both Lake of the Woods and the Winnipeg River. These reductions will continue throughout the months of September and October unless wet conditions develop. With regular reductions in outflow, the river will see a gradual drop in levels, providing those along the river time to adjust their docks as the river falls. Given outflow cuts from Rainy Lake, increasing evaporation, and dry medium-range weather forecasts, the level of Lake of the Woods will continue to see a sharp decline regardless of the outflow reductions. This approach is covered in the Board’s Regulation Strategy, adopted in August, which targets lower levels for both the lake and river by the end of October to assist with post-flood repairs.
The current level of Lake of the Woods is 323.35 m (1060.8 ft), over 95th percentile level for this time of year. The average lake level declined by 15 cm (5 in) over the past week and is expected to decline by 14-16 cm (5 in) over the next week. Lake of the Woods outflow is scheduled to decrease to 1075 m3/s on Tuesday, September 13th and to 1000 m3/s on Thursday, September 15th.
Winnipeg River levels are expected to decline by 22 cm (9 in) below the Norman Dam, by 18 cm (7 in) above the Dalles and by 14 cm (5 in) at Minaki following each flow reduction.
The current level of Lac Seul is 356.40 m (1169.3 ft), a 40th percentile level for this time of year. The lake level declined by 6 cm (2 in) over the past week and is expected to decline by 4 to 6 cm (1 to 2 in) over the next week. Lac Seul authorized outflow is scheduled to decrease to 300 m³/s on Monday, September 12th.
Manitoba Hydro has provided the following forecast for the Winnipeg River through the Whiteshell.