March 2023

The current level of Lake of the Woods is 322.43 m (1057.8 ft), a 40^th percentile level for this time of year. The average lake level remained stable over the past week and is expected to decline by up to 4 cm (1.5 in) over the next week. Lake of the Woods authorized outflow will return to 425 m³/s following today’s outage and there are no further changes scheduled.

The current level of Lac Seul is 354.82 m (1164.1 ft), a 40^th percentile level for this time of year. The lake level declined by 3 cm (1 in) over the past week and is expected to decline by less than 2 cm (1 in) over the next week. Lac Seul authorized outflow decreased to 150 m³/s today, Thursday March 30^th with no further changes scheduled.

Below is an update to the planned outage of the Norman and Kenora Powerhouses, originally posted on March 23.

On Wednesday, March 30 (one day earlier than previous noted), Hydro One will be conducting a full day outage that will result in temporary disconnection of the Norman Generating Station and Kenora Generating Station from the grid. During the outage, neither facility will be able to pass flow through turbines and this will result in a temporary drop in the level of the Winnipeg River near Kenora. To limit the effect of the outage on river levels, the LWCB has directed the dam operators to add flow through the log sluices at the Norman Dam (currently all log sluices are fully closed).

River levels will fluctuate before, during and after the outage as dam operations are adjusted and this may cause the ice on the river to shift. The LWCB recommends taking precautions when on or near the Winnipeg River between March 29 and March 31.

Minor fluctuations in the river level are expected the day before and the day after the outage as flow is adjusted between the Norman powerhouse and the log sluices.

On March 30, river levels are expected to decrease as follows.

Below the Norman Dam: 15- 17 cm (6-7 in)

Above Kimberly Rapids: 12-13 cm (5 in)

Winnipeg River Marina: 10 (4 in)

Near Locke Bay and Above Myrtle Rapids: 10 cm (4 in)

Above the Dalles and Throat Rapids: 8 cm (3 in)

Minaki: no change

Following the outage at the end of the afternoon on March 30, flow will return to the authorized rate of 425 m³/s and the river will rise back to the pre-outage level range.

On Thursday, March 31, Hydro One will be conducting a full day outage that will result in temporary disconnection of the Norman Generating Station and Kenora Generating Station from the grid. During the outage, neither facility will be able to pass flow through turbines and this will result in a temporary drop in the level of the Winnipeg River near Kenora. To limit the effect of the outage on river levels, the LWCB has directed the dam operators to add flow through the log sluices at the Norman Dam (currently all log sluices are fully closed).

River levels will fluctuate before, during and after the outage as dam operations are adjusted and this may cause the ice on the river to shift. The LWCB recommends taking precautions when on or near the Winnipeg River between March 30 and April 1.

On March 31, river levels are expected to decrease as follows.

Below the Norman Dam: 55 cm (22 in)

Above Kimberly Rapids: 39 cm (15 in)

Winnipeg River Marina: 26 cm (10 in)

Near Locke Bay and Above Myrtle Rapids: 26 cm (10 in)

Above the Dalles and Throat Rapids: 22 cm (9 in)

Minaki: no change

Following the outage, flow will return to the authorized rate of 425 m³/s and the river will rise back to the pre-outage level range.

The current level of Lake of the Woods is 322.43 m (1057.8 ft), a 40^th percentile level for this time of year. The average lake level changed little over the past week and is expected to remain stable over the next week. The last of the gradual increases to Lake of the Woods authorized outflow continue this week as follows:

March 21: from 375 to 390 m³/s

March 22: 405 m³/s

March 23: 425 m³/s

Each flow adjustment will result in the Winnipeg River near Kenora rising by roughly 3 cm ( 1 in). The Winnipeg River level at Minaki will not be affected by these adjustments.

The current level of Lac Seul is 354.86 m (1164.2 ft), a 35^th percentile level for this time of year. The lake level declined by 4.3 cm (1.5 in) over the past week and is expected to decline by 3 to 5 cm (2 in) over the next week. Lac Seul authorized outflow is 200 m³/s with no scheduled changes.

Spring Strategy

On March 7, the LWCB held its spring Regulation Meeting, attended by specific interest groups and resource agencies, and adopted its Spring Regulation Strategy. The strategy outlines regulation targets for various inflow conditions for the period of March to the end of June. Winter conditions were also reviewed at the meeting, with measured snow depth close to normal throughout the basin and other factors resulting in a winter severity that was less than normal.

For Lake of the Woods, the strategy targets a lower end of March level to assist with property repairs following the 2022 flood. Summer level targets are also set slightly lower than typical for this same purpose. With higher snow depth in the headwaters of the larger Lake of the Woods basin, the risk of insufficient inflow for lake refill is reduced this spring.

For Lac Seul, the strategy targets mid-April levels that meet preferences for fish spawning and are slightly higher than the typical range. Inflows to Lac Seul have been below normal over the course of the winter and with the snowpack close to normal, there is no elevated risk of high spring inflows.

The current level of Lake of the Woods is 322.42m (1057.8 ft), a 35^th percentile level for this time of year. The average lake level rose by 1 cm (0.5 in) over the past week and is expected to change little over the next week. Upstream, the International Joint Commission’s Water Levels Committee set targets for Namakan Lake and Rainy Lake at the end of March at the lower end of the respective Rule Curve ranges and the dam operators have increased outflow from both lakes to meet these targets. This has resulted in a modest increase in inflow to Lake of the Woods for the remainder of March. In response, the LWCB is gradually increasing outflow Lake of the Woods to maintain storage room ahead of the spring melt. The following flow adjustments are planned over the next week:

March 16: from 300 to 315 m³/s

March 17: 330 m³/s

March 18: 345 m³/s

March 19: 360 m³/s

March 20: 375 m³/s

Each flow adjustment will result in the Winnipeg River near Kenora rising by roughly 3 cm ( 1 in). The Winnipeg River level at Minaki will not be affected by these adjustments.

The current level of Lac Seul is 354.87 m (1164.3 ft), a 30^th percentile level for this time of year. The lake level declined by 7 cm (3 in) over the past week and is expected to decline by 4 to 6 cm (2-3 in) over the next week. Lac Seul authorized outflow will be reduced from 250 m³/s to 200 m³/s on Thursday, March 16.

The current level of Lake of the Woods is 322.41 m (1057.8 ft), a 25^th percentile level for this time of year. The average lake level remained stable over the past week and is expected to remain stable over the next week. Lake of the Woods authorized outflow is 300 m³/s with no scheduled changes.

The current level of Lac Seul is 354.95 m (1164.5 ft), a 30^th percentile level for this time of year. The lake level declined by 10 cm (4 in) over the past week and is expected to decline by 7 to 9 cm (3 to 3.5 in) over the next week. Lac Seul authorized outflow is 310 m³/s with scheduled decreases to 250 m³/s today, Thursday March 9^th and 200 m³/s Thursday March 16^th.

The current level of Lake of the Woods is 322.41 m (1057.8 ft), a 20^th percentile level for this time of year. The average lake level declined by 2 cm (0.5 in) over the past week and is expected to remain stable over the next week. Lake of the Woods authorized outflow is 300 m³/s with no scheduled changes.

The current level of Lac Seul is 355.05 m (1164.8 ft), a 30^th percentile level for this time of year. The lake level declined by 9 cm (3.5 in) over the past week and is expected to decline by 7 to 8 cm (3 in) over the next week. Lac Seul authorized outflow is 310 m³/s with no scheduled changes.