International Rainy-Lake of the Woods Board Water Levels Committee High Water and Flow Bulletin

Date

Extremely high flow conditions have developed across the Rainy River watershed, including flows into Namakan Lake and Rainy Lake, following record high precipitation in April.

These high flow conditions have led to the water levels of Namakan Lake and Rainy Lake rising above their respective Rule Curves established by the International Joint Commission.

As of May 5, Namakan Lake is 34 cm (13 in) above the Upper Rule Curve, and 36 cm (14 in) below the All Gates Open level set by the IJC. At the All Gates Open level, the two dams at the outlet of Namakan Lake must be fully opened. With ongoing high flows anticipated, it is expected that Namakan Lake will rise above the All Gates Open level within the next 7 days. However, the dams have already been fully open since April 26.

As of May 5, Rainy Lake is 33 cm (13 in) above the Upper Rule Curve, and 14 cm (5.5 in) below the All Gates Open level set by the IJC. At the All Gates Open level, all 15 gates at the dam at Fort Frances-International Falls must be opened. With ongoing high flows anticipated, it is expected that Rainy Lake will also rise above the All Gates Open level within the next 7 days. The dam operators have been opening gates to pass additional flow as the lake level has risen. The last remaining gate is scheduled to be opened on May 5.

Due to the extremely high flow conditions across the watershed, water levels are expected to continue to rise over the coming weeks. Wet weather could result in a faster rate of rise.

Areas that have been negatively affected by past high water events on these lakes should make preparations for high water levels returning.

Updates on dam operations will continue to be provided by the Water Levels Committee.

For updated information on flood risk, please refer to the National Weather Service and Province of Ontario websites.