Winnipeg River, already flowing at a record volume, slated to rise even higher

The Winnipeg River is flowing at a record volume in Manitoba because officials no longer have any other option to control flooding across a vast swath of northwestern Ontario and northern Minnesota.

Flooding on the Winnipeg River, which is running at about three-and-a-half times higher its usual volume this time of year, has already forced hundreds of people from their homes and washed out roads in Whiteshell Provincial Park.

This is the result of inflows that are only expected to increase in the coming days, raising water levels up to two-thirds of a metre higher in some locations in Manitoba.

‘We are seeing record inflows into the Winnipeg River system, inflows that we’ve we’ve never seen before,” said Scott Powell, Manitoba Hydro’s communications director.

According to the Lake of the Woods Control Board, the river was flowing at 120,000 cubic feet per second on Tuesday at Seven Sisters Falls, which is more than the water which flowed down the Red River this spring at the height of this year’s flood.

Officials on both sides of the Manitoba-Ontario border say the volume is unprecedented but there is nothing any agency can do to reduce the flows.

The river drains an area larger than the Maritimes and almost all of it is flooding, said Matthew DeWolfe, executive engineer with the Lake of the Woods Control Board.

“There’s literally nowhere else to put the water,” DeWolfe said Tuesday in an interview from his office in Ottawa.

“Basically, the watershed is full and there’s nowhere for it to go except to flow downstream, and unfortunately, all that area drains into that very narrow channel we call the Winnipeg River.”

The Lake of the Woods Control Board is responsible for managing water levels on both Lake of the Woods, which drains directly into the Winnipeg River, as well as Lac Seul, which drains into the Winnipeg River through the English River.

The board has been forced to release water from Lac Seul because a dam on that lake could be threatened if water exceeds the maximum level, DeWolfe said.

Lake of the Woods rising

The board is also draining as much water as it can from Lake of the Woods, where the lake level has now risen to the point where wave action in its southern basin threatens residential properties and agricultural land in Minnesota, Ontario and one small corner of Manitoba, Buffalo Point, that juts into the lake.

“That area is very flat and it’s a very unstable shoreline,” said DeWolfe, explaining that the southwestern shore of Lake of the Woods is grassy and shallow like a prairie lake, not rocky and steep the way it is at Kenora.

“It’s a very open bay at the south end of Lake of the Woods and when the winds, when they pick up, they create huge waves.”

In its latest forecast for Lake of the Woods, the control board expects the lake to rise another 10 to 13 centimetres over the next week. At the same time, flows out of Lac Seul continue to be high.

That means flows along the Winnipeg River should continue to rise for several more weeks, DeWolfe said.

“It’s a very, very gradual rate of rise right now, unless we get a significant amount of precipitation,” he said, adding he could not predict with any certainty when waters will recede, given the vast area experiencing flooding.

“We’re dealing with conditions that have never been seen before, so there’s nothing to compare it to.”

Hydro can’t hold it back

Manitoba Hydro, which operates six dams on the Winnipeg River west of the Ontario border, has no ability to hold any water back, communications director Scott Powell said.

“These are run-of-river plants, as we call them. We don’t have large reservoirs in front of any of our stations on the Winnipeg River,” Powell said Tuesday in an interview.

“So as those flows come in, we have to pass them down the river, through our spillways, through our generating stations and turbines and continue to pass it down to move that water,” he added.

“No matter what we do in certain spots, there’s a limit to how fast that certain areas of the of the river will drop because of natural restrictions in the natural watercourse.”

On Tuesday, officials with Manitoba Infrastructure and Transportation said they were focused on keeping property owners safe and will consider a compensation program later.

Jay Doering, a University of Manitoba civil engineering professor, said cottagers along the Winnipeg River may have to start making some of the same decisions Red River Valley property owners made after the 1997 Flood of the Century destroyed or damaged thousands of homes.

“You have to have that reality check: Am I going to rebuild or am I going to walk away from this,” Doering said Tuesday in an interview. 

“And if I’m able to rebuild and lift it higher, is it going to look ridiculous way up on stilts?”

Powell said he wouldn’t speculate on the necessity to move or raise any cottages or homes along the Winnipeg River just yet.

“These are certainly the highest inflows we’ve seen since 1907, when records began. So it’s certainly not a common occurrence,” he said.

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