Rainy Lake water levels to get tweaked following public input
Apr 16, 2018 10:55AM
● By Editor
Concerns about a potential wet spring, late ice-out and a heavy snow pack have lead to water level adjustments on Rainy Lake.
A joint Canadian and American water level committee met with stakeholders in early March, in International Falls.
Concerns about the forecast and snow pack lead the water level committee to make the decision.
Matt DeWolfe is the Canadian Engineering Advisor for the International Rainy-Lake of the Woods Watershed board.
He says the idea is to allow Rainy Lake to take a little extra water this spring.
DeWolfe also said the late ice out expected this spring could create a high water scenario on the system.
"You get a combination of all the rainfall as well as all the snow melt happening at once. And that can really swell rivers," he said. "And add a lot of inflow to the lakes can make things rise pretty quickly."
Rainy lake is a boundary water between Canada and the U.S. and Ontario and Minnesota and it's managed under the authority of the International Joint Commission.
The IJC is the body that regulates the bi-national water between the two countries.
Dewolfe said the IJC has what are know as "rule curves" to regulate Rainy Lake and Namakan Lake, which is upstream of Rainy.
He said a rule curve is basically a set lower and upper limit of water levels that should be targeted, and it varies throughout the year.
"In the winter they will draw the water down,to make room for spring melt. In the summer, the water levels will be higher for navigation and recreation purposes," he said. "That water level range between the upper and lower band is between 25 to 60 cm. "
DeWolfe said the day to day to management of water levels is done by the operators of the dams.
He said they generally they try to target for the middle of that rule curve range.
DeWolfe said on occasion, the water levels committee, which monitors how well the rule curve operations are going, can direct the operators of the dams to target beyond the middle range of the rule curve band. So they can target lower or higher based on conditions.
DeWolfe said the revised target range is the lowest 10 cm. of the Rule Curve Band.
He said the IJC and water levels committee will continue to monitor the progress of the April freshet and make a determination on what will happen in May.