Secretariat

Although the basin received high rainfall over the last few days, so far inflows have been manageable and lake level are rising within their normal ranges.  Most of the basin received 50 to 60 mm on Tuesday evening and Wednesday.  This resulted in very rapidly increasing flows in the tributaries and a sudden jump in lake levels (8 cm at Lac Seul and 5 cm at Lake of the Woods).  Forecasts are predicting a chance for some moderate rainfall this Friday and Saturday, followed by much drier conditions next week.  This means high tributary flows and lake inflows will be temporary.

The current level of Lake of the Woods is 322.74 m (1058.86 ft), a 40^th percentile level, within the normal range for this time of year. The average lake level increased by 7 cm (3 in) over the last week and is expected to increase by 5 to 12 cm (2 to 5 in) over the next week, depending on precipitation amounts and upstream flow changes. Lake of the Woods authorized outflow is 400 m³/s with planned outflow increases to 480 m³/s tomorrow May 24^th and 550 m³/s Monday May 27^th. More outflow increases may be required depending on the amount of the rainfall over the next week.  

These flow changes will cause a large and rapid increase in levels along the Winnipeg River. By Tuesday, water levels will have increased by approximately 35 cm, (14 in) directly downstream of the Norman Dam and by 20 cm (8 in) above the Dalles. The level at Minaki will not be affected by these flow changes, but could increase due to local inflow.

The current level of Lac Seul is 355.25 m (1165.5 ft), a 40^th percentile level, within the normal range for this time of year. The average lake level increased by 14 cm (5.5 in) over the past week and is expected to increase by 17 to 22 cm (6.5 to 8.5 in) over the next week. Lac Seul authorized outflow is 200 m³/s with a planned increase to 240 m³/s Friday May 24^th.

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.

Conditions in the Winnipeg River basin are beginning to change quickly. The basin has received larger amounts of precipitation over the past week and over the weekend. Most of the basin received a 7-day total of 25 mm with some areas totaling up to 40 mm.

A low pressure system is forecast to impact the Winnipeg River basin starting this evening, bringing heavy rainfall over the next couple of days. Environment Canada has issued a Rainfall Warning covering the entire basin. This system could bring up to 80 mm (3 in) of rainfall tonight through tomorrow. Forecasts indicate weekly totals could exceed 150 mm (6 in).

This large amount of rainfall will cause flows in tributaries and inflows to the major lakes to rise quickly. Although outflow increases are being made in advance of the upcoming precipitation at Namakan Lake, Rainy Lake and Lake of the Woods, outflows are lower than the expected inflows. Therefore, lake levels will rise and additional, larger outflow increases will be required at Lake of the Woods and may be required at Lac Seul. These outflow increase will be made in consideration of downstream impacts, but levels along the English and Winnipeg Rivers are expected to rise considerably over the next week. 

The current level of Lake of the Woods is 322.72 m (1058.79 ft), a 40^th percentile level, within the normal range for this time of year. The average lake level increased by 6 cm (2.5 in) over the last week and is expected to increase by 15 to 35 cm (6 to 14 in) over the next week, depending on precipitation amounts. Lake of the Woods authorized outflow is 200 m³/s with planned outflow increases to 225 m³/s today May 21^st, 300 m³/s Wednesday May 22^nd, and 400 m³/s Thursday May 23^rd. More outflow increases may be required depending on the severity of the rainfall over the next couple of days.  

Flow changes this week will cause a large and rapid increase in levels along the Winnipeg River. By Friday, water levels will have increased by approximately 40 cm, (16 in) directly downstream of the Norman Dam and by 16 cm (6 in) above the Dalles. The level at Minaki will not be affected by these flow changes, but could increase due to local inflow.

The current level of Lac Seul is 355.2 m (1165.4 ft), a 40^th percentile level, within the normal range for this time of year. The average lake level increased by 13 cm (5 in) over the past week and is expected to increase by 30 to 46 cm (12 to 18 in) over the next week. Lac Seul authorized outflow is 150 m³/s with a planned increase to 200 m³/s Wednesday May 22^nd.

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.

Spring conditions in the Winnipeg River basin have so far been favourable, with an early freshet followed by moderate amounts of rainfall. Water levels on both Lake of the Woods and Lac Seul have been rising steadily within the normal range. Some Regulation Strategy targets that have been, or are on track to be achieved include the May 15^th preferred water level of 355.1 m on Lac Seul for fisheries, and the end-of-May water level target of 322.7 m (1058.7 ft) for Lake of the Woods under moderate inflow conditions. Flows on the English and Winnipeg Rivers are also slowly rising with steady precipitation and small outflow increases from Lake of the Woods.

The current level of Lake of the Woods is 322.67 m (1058.61 ft), a 40^th percentile level, within the normal range for this time of year. The average lake level increased by 5 cm (2 in) over the last week and is expected to increase by 2 to 5 cm (1 to 2 in) over the next week, depending on precipitation amounts. Lake of the Woods authorized outflow is 200 m³/s with no changes scheduled at this time.

The current level of Lac Seul is 355.10 m (1165.0 ft), a 40^th percentile level, within the normal range 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 8 to 12 cm (3 to 5 in) over the next week. Lac Seul authorized outflow is 150 m³/s with no changes scheduled.

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The LWCB Basin Data page will not be updated on Monday, May 20^th (Victoria Day in Canada). Daily data updates and publication will resume on Tuesday, May 21^st.

The current level of Lake of the Woods is 322.62 m (1058.45 ft), a 40^th percentile level, within the normal range for this time of year. The average lake level increased by 10 cm (3 in) over the last week and is expected to increase by 1 to 4 cm (1 to 2 in) over the next week. Lake of the Woods authorized outflow was increased to 175 m³/s today, May 9^th, and is scheduled to increase to 200 m³/s on Monday, May 13^th.

Each of these flow changes will cause the level of the Winnipeg River to increase by approximately 4 cm (2 in) directly downstream of the Norman Dam and by 1 cm (0.5 in) above the Dalles. The level at Minaki will not be affected by these flow changes.

The current level of Lac Seul is 355.00 m (1164.70 ft), a 40^th percentile level, within the normal range for this time of year. The lake level increased by 14 cm (5 in) over the past week and is expected to increase by 5 to 8 cm (2 to 3 in) over the next week. Lac Seul authorized outflow is 150 m³/s with no changes scheduled.

If you have any questions about the survey or need assistance, please contact the Secretariat at secretariat@lwcb.ca or by calling 1-800-661-5922.

With the precipitation observed early in the week, tributaries in the southern part of the basin have started rising. Inflows to the major lakes are also increasing as a result. There is some rain forecast across the basin over the next few days before the forecast becomes dryer and inflows could potentially decrease.

The current level of Lake of the Woods is 322.54 m (1058.20 ft), a 35th percentile level, within the normal range for this time of year. The average lake level increased by 5 cm (2 in) over the last week and is expected to increase 3 to 5 cm (1.2 to 2 in) over the next week, depending on precipitation amounts. Lake of the Woods authorized outflow is 150 m³/s with no changes scheduled.

The current level of Lac Seul is 354.88 m (1164.30 ft), a 35th percentile level, within the normal range for this time of year. Lake inflows and levels continue to increase. The lake level increased by 13 cm (5 in) over the past week and is expected to increase by 7 to 11 cm (2.8 to 4.3 in). Lac Seul authorized outflow is 150 m³/s with no changes currently scheduled.

The Winnipeg River basin received more precipitation than was expected over the last week, especially in the North and East.

There are two systems in the forecast potentially bringing more precipitation, with totals for the upcoming week between 30 and 40 mm. Much of this precipitation is expected to fall Friday April 26th through Saturday April 27th with more coming early next week.

Tributary flows, and lake inflows and levels have started rising into the normal range. The rain has helped the basin recover from the below average snowpack and lack of runoff from snowmelt. However, continued rainfall into May and June will be required to sustain normal flows and levels throughout the spring and summer.

The current level of Lake of the Woods is 322.48 m (1058.01 ft), a 40^th percentile level, within the normal range for this time of year. The average lake level increased by 2 cm (1 in) over the last week and is expected to increase 5 to 11 cm (2 to 4 in) over the next week, depending on precipitation amounts. Lake of the Woods authorized outflow is 150 m³/s with no changes scheduled.

The current level of Lac Seul is 354.74 m (1163.85 ft), a 35^th percentile level, within the normal range for this time of year. Lake inflows and levels increased rapidly over the last week in response to higher-than-expected precipitation amounts. The lake level increased by 10 cm (4 in) over the past week and is expected to increase by 12 to 18 cm (5 to 7 in). Lac Seul authorized outflow is 150 m³/s with no changes currently scheduled.

The current level of Lake of the Woods is 322.46 m (1057.94 ft), a 35^th percentile level, within the normal range for this time of year. The average lake level increased by 3 cm (1.2 in) over the last week and is expected to increase 1 to 3 cm (0.4 to 1.2 in) over the next week, depending on precipitation amounts. Lake of the Woods authorized outflow is 150 m³/s with no changes scheduled..

The current level of Lac Seul is 354.64 m (1163.52 ft), a 25^th percentile level, which is at the bottom of the normal range for this time of year. The lake level increased by 5 cm (2 in) over the past week and is expected to remain relatively stable over the next week depending on precipitation amounts. Lac Seul authorized outflow is 150 m³/s with no changes currently scheduled.

The current level of Lake of the Woods is 322.43 m (1057.84 ft), a 30^th percentile level, within the normal range for this time of year. The average lake level increased by 1 cm (0.5 in) over the last week and is expected to remain relatively stable, increasing by up to 6 cm (2.4 in) over the next week, depending on precipitation amounts. Lake of the Woods authorized outflow was decreased to 150 m³/s on Wednesday, April 10^th.

The current level of Lac Seul is 354.56 m (1163.25 ft), a 25^th percentile level, which is at the bottom of the normal range for this time of year. The lake level declined by 3 cm (1.2 in) over the past week and is expected to remain relatively stable, increasing up to 3 cm (1.2 in) over the next week. Lac Seul authorized outflow is 150 m³/s with no changes currently scheduled.

The current level of Lake of the Woods is 322.42 m (1057.8 ft), a 35^th percentile level, within the normal range for this time of year. The average lake level declined by 1 cm (0.5 in) over the last week and is expected to remain relatively stable, increasing by up to 1.5 cm (0.6 in) over the next week. Lake of the Woods authorized outflow will decrease to 175 m³/s on Monday, April 8^th and to 150 m³/s on Wednesday, April 10^th.

Each of these flow changes will cause the level of the Winnipeg River to decrease by approximately 3 cm (1 in) directly downstream of the Norman Dam and by 1 cm (0.5 in) above the Dalles. The level at Minaki will not be affected by these flow changes.

The current level of Lac Seul is 354.59 m (1163.35 ft), a 25^th percentile level, which is at the bottom of the normal range for this time of year. The lake level declined by 1 cm (0.5 in) over the past week and is expected to remain relatively stable, increasing up to 1 cm (0.5 in) over the next week. Lac Seul authorized outflow is 150 m³/s with no changes currently scheduled.