Duane Hicks
With the Emo Walleye Classic set to go tomorrow, the Rainy River is at a 10-year high for this time of year, having come up six feet in the last week.
The water level on Rainy Lake, meanwhile, rose by a foot over the past seven days—thanks to four-five inches of rain that fell over the Victoria Day weekend.
There also was another seven-eight inches from the consequent inflow from Namakan Lake and tributaries such as Turtle River, noted Matt DeWolfe, engineering advisor to the International Rainy-Lake of the Woods Watershed Board.
This meant the outflow from the lake to the river had to be increased.
“There’s a big difference,” DeWolfe said. “People on the river really get the impact of those large outflow increases from the lake, and the board is aware of that and is certainly cognisant of the impact that has on people downstream.
“But at this time, there shouldn’t be significant increases in outflow unless we get a lot more rain,” he added.
“The river level won’t come up a great deal more in the next few days [but] it will continue to rise a bit.”
DeWolfe said Rainy Lake went above the IJC’s upper rule curve level over the last couple days, but it still is a foot below what’s called the “all gates open level” when the IJC mandates all of the dam gates be opened.
“And we’re not at the peak summer level for the IJC rule curve,” he noted. “At this point, the rule curves are going up through May to the start of July, when they level off.
“So we’re not as high as the summer upper rule curve right now.
“For a summer level, this level isn’t bad, but the concern is it’s rising quickly,” DeWolfe conceded. “And if we do get more rain, then we’re going to get into a high water situation.
“That’s certainly a lot of the concerns that local people have been passing on.”
H2O Power began opening gates at the dam here Friday in anticipation of the forecast for heavy rain, and has continued to open more steadily to keep up with the increasing inflow.
Prior to Friday, no gates were opened. Two canal gates then were opened Friday.
As of today, all five canal gates and six of the 10 dam gates are open.
For the time being, 11 gates will be the limit.
“That’s really the capacity right now for Rainy Lake to pass water,” DeWolfe explained. “Upstream of the dam, further up at really the start of the Rainy River, near Pither’s Point in Fort Frances, there’s a constriction in the river there.
“And when the lake levels are sort of moderate, not too high as they are now—they really limit the amount of water that can pass through the dam.
“That’s really the control, it’s at that point right now,” he added.
“So the dam can only really pass what’s coming through that point in the river.”
DeWolfe said as we get to higher levels, that control no longer has an effect and it’s really what happens at the dam.
“But right now, there would be no point in opening the additional gates,” he remarked.
“All that does is drain the water right in front of the dam area, and doesn’t help the level on the lake at all.”
DeWolfe said the five-day forecast is favourable, meaning it will be pretty dry. As such, the flow from Namakan Lake into Rainy Lake will decrease over the next couple of days.
“That will certainly help the Rainy Lake level issue, but where Rainy Lake level peaks over the next week is hard to predict,” he conceded.
“But I don’t anticipate we’re going to get much above the summer upper rule curve line and certainly not up to the ‘all gates open’—unless we get a lot more rain.”
The International Rainy-Lake of the Woods Watershed Board (which has replaced the International Rainy Lake Board of Control) has a water levels committee.
That committee is in touch with area residents, as well as H2O Power, on a daily basis, and is staying on top of conditions, said DeWolfe.
For more information, the public can talk to board staff by calling toll-free 1-800-661-5922.
