Although conditions are expected to be dry over the Victoria Day long weekend, forecasts are indicating above-normal precipitation from May 23 onwards. Both, Environment and Climate Change Canada’s probabilistic forecast, and the National Weather Services’ 6-10 day outlook, are predicting above-normal precipitation starting mid to late next week. Tributary flows, lake inflows and lake levels are already high across the southern half of the basin and this precipitation will amplify those conditions.

At Lake of the Woods and on the Winnipeg River, additional outflow increases will be required to slow the rate of rise on the lake. At these flow rates, the level along the Winnipeg River is expected to continue to rise and levels at Minaki will also rise more with each outflow increase.

In the northern half of the basin, flows and levels are currently in the low-normal range. Depending on the amount of precipitation impacting the Lac Seul and English River basins, outflow changes may or may not be required to maintain normal levels and flow rates.

The current level of Lake of the Woods is 322.96 m (1059.6 ft), a 65^th percentile level for this time of year. The average lake level increased by 10 cm (4 in) over the past week and is expected to increase by 7 to 9 cm (2 to 3 in) over the next week. Lake of the Woods authorized outflow is 800 m³/s with no changes scheduled at this time.

The current level of Lac Seul is 355.29 m (1165.6 ft), a 50^th percentile level for this time of year. The lake level increased by 16 cm (6 in) over the past week and is expected to increase by 11 to 17 cm (4 to 7 in) over the next week. Lac Seul authorized outflow is 100 m³/s with no changes scheduled.

High local inflow conditions in the headwaters of the Rainy-Namakan basin are resulting in additional increases to Rainy Lake outflow. Inflows to Lake of the Woods therefore remain high and the lake level continues to rise. While balancing rising flows on the Winnipeg River, another small increase to Lake of the Woods outflow is scheduled to slow the rate of rise on the lake.

Lake of the Woods outflow will increase to 800 m³/s tomorrow, Wednesday, June 17. This flow change will cause levels along the Winnipeg River to increase by 10 cm (4 in) below the Norman Dam, 6 cm (2 in) above the Dalles and 7 cm (3 in) at Minaki.

The current level of Lake of the Woods is 322.86 m (1059.2 ft), a 65^th percentile level for this time of year. The average lake level increased by 9 cm (3 in) over the past week and is expected to increase by 6 to 8 cm (2 to 3 in) over the next week. Lake of the Woods authorized outflow is 750 m³/s with no changes scheduled.

The current level of Lac Seul is 355.13 m (1165.1 ft), a 55^th percentile level for this time of year. The lake level increased by 16 cm (6 in) over the past week and is expected to increase by 16 to 18 cm (6 to 7 in) over the next week. Lac Seul authorized outflow is 100 m³/s with no changes scheduled.

Recent rainfall has impacted the Lake of the Woods local basin and the upstream Rainy-Namakan basin. Inflows to Lake of the Woods are expected to rise. The level also continues to rise above the preferred lake levels for this time of year. With the risk of more rain in the forecast and to slow the rate of level rise, additional outflow increases are planned this week.

Lake of the Woods authorized outflow will increase to 725 m³/s today, May 8 and to 750 m³/s tomorrow, May 9.

This flow change will cause levels along the Winnipeg River to increase by a total of:

• 15 cm (6 in) directly below the Norman Dam
• 10 cm (4 in) above the Dalles
• 7 cm (3 in) at Minaki

The current level of Lake of the Woods is 322.76 (1058.9 ft), a 65^th percentile level for this time of year. The average lake level increased by 8 cm (3 in) over the past week and is expected to increase by 7 to 10 cm (3 to 4 in) over the next week. Lake of the Woods authorized outflow will increase to 700 m³/s tomorrow, Friday, May 5. Additional outflow increases are likely next week as outflows from Rainy Lake continue to increase and the forecast indicates a chance of rain on most days.

Tomorrow’s outflow change will cause levels along the Winnipeg River to increase by 7 cm (3 in) directly below the Norman Dam and by 5 cm (2 in) above the Dalles. Although this outflow change will not affect the level at Minaki, levels there can be expected to start increasing with any subsequent outflow increase.

The current level of Lac Seul is 354.97 m (1164.6 ft), a 55^th percentile level for this time of year. The lake level increased by 8 cm (3 in) over the past week and is expected to increase by 15 to 20 cm (6 to 8 in) over the next week. Lac Seul authorized outflow is 100 m³/s with no changes scheduled.

The current level of Lake of the Woods is 322.68 m (1058.7 ft), a 60^th percentile level for this time of year. The average lake level increased by 12 cm (4 in) over the past week and is expected to increase by 5 to 7 cm (2 in) over the next week. Lake of the Woods authorized outflow was increased to 675 m³/s today and currently, there are no additional increases scheduled.

The current level of Lac Seul is 354.89 m (1164.3 ft), a 50^th percentile level for this time of year. The lake level increased by 5 cm (2 in) over the past week and is expected to increase by 7 to 10 cm (2.5 to 4 in) over the next week. Lac Seul authorized outflow is 100 m³/s with no changes scheduled.

Inflow to Lake of the Woods remains high and as a result, the level of Lake of the Woods increased by 15 cm (5 in) over the last week. With some precipitation in the forecast, another outflow increase is scheduled this week to slow the rate of level rise.

Lake of the Woods authorized outflow will increase to 675 m³/s on Thursday, April 27. This flow change will cause levels along the Winnipeg River to increase by 14 cm (5 in) directly below the Norman Dam and by 9 cm (4 in) above the Dalles. The level at Minaki will not be affected.

A precipitation system will impact southern portions of the Winnipeg River basin this Friday, April 21. Snow is expected, with amounts ranging from 10 to 15 cm (4 to 6 in) and in some locations as high as 25 cm (10 in). This precipitation will, in the short term, cause increased flows and levels in the rivers and lakes. In the long-term, this added snowpack will increase the snow water content and as it melts will cause river flows and lake inflows to remain at above normal levels. Additional larger outflow increases are scheduled at Lake of the Woods to help slow the rate of level rise. The ice cover is no longer in place on the Winnipeg River, minimizing the impact of river level rise due to these outflow increases.

The current level of Lake of the Woods is 322.57 m (1058.3 ft), a 50^th percentile level for this time of year. The average lake level increased by 14 cm (5 in) over the past week and is expected to increase by 13 to 16 cm (5 to 6 in) over the next week. Lake of the Woods authorized outflow will increase to 575 m³/s on Friday, April 21 (slightly higher than planned) and again to 625 m³/s on Monday, April 24.

Each of these outflow changes will cause levels along the Winnipeg River to increase by 14 cm (5 in) directly below the Norman Dam and by 8 cm (3 in) above the Dalles for a total rise of 28 cm (11 in) and 16 cm (6 in) respectively at each location. These flow changes will not affect the level at Minaki.

Less precipitation is forecast to impact the English River basin on April 21st. In this basin, freshet is slow to begin and river flows and lake inflows are at low-normal conditions. As such, an outflow reduction was scheduled at Lac Seul to allow for the lake level to start rising gradually in anticipation of higher spring inflows.

The current level of Lac Seul is 354.84 m (1164.2 ft), a 50^th percentile level for this time of year. The lake level increased by 3 cm (1 in) over the past week and is expected to increase by 6 to 8 cm (2 to 3 in) over the next week. Lac Seul authorized outflow was reduced to 100 m³/s on April 20.

Inflow to Lake of the Woods continues to rise and is expected to remain high over the next week. Another round of precipitation is forecast to impact the southern portion of the Winnpeg River basin at the end of the week and flows on the Rainy River are expected to increase.

To slow the rate of level rise on Lake of the Woods and achieve a gradual refill of the lake, staged outflow increases will continue with increases of 25 m³/s per day to minimize impacts downstream on the Winnipeg River. Authorized outflow will increase to 500 m³/s on April 19, to 525 m³/s on April 20 and to 550 m³/s on April 21.

Each of these outflow changes will cause levels along the Winnipeg River to increase by 6 cm (2 in) directly below the Norman Dam and by 3 cm (1 in) above the Dalles for a total rise of 20 cm (8 in) and 11 cm (4 in) respectively at each location by Friday. These flow changes will not affect the level at Minaki.

Inflow to Lake of the Woods increased over the weekend due to precipitation and increased flows from the Rainy River. As a result, the level of Lake of the Woods increased by 7 cm (2.5 in) over the last three days.

To slow the rate of level rise and achieve a gradual refill of the lake, staged outflow increases are planned this week starting with an increase to 450 m³/s today, April 17, and another increase to 475 m³/s tomorrow, April 18. Each of these outflow changes will cause levels along the Winnipeg River to increase by 6 cm (2 in) directly below the Norman Dam and by 3 cm (1 in) above the Dalles. These flow changes will not affect the level at Minaki.

As inflow stabilizes and the accuracy of this week’s precipitation forecast improves, the need for additional outflow increases will be assessed.