Manitoba government expects spring flooding but not a threat to community defences

WINNIPEG – The Manitoba government is expecting flooding along the Red River south of Winnipeg this year, although not enough to overcome community dikes and diversions.

The province’s March outlook says the flood risk is low or moderate along many rivers including the Assiniboine, Pembina, Roseau and Souris.

But the Red River is at risk because of heavy snowfall upstream in North Dakota.

The Manitoba Hydrologic Forecast Centre says it’s likely that the Red River Floodway, which diverts rising water around Winnipeg, will be operated this spring.

The Portage Diversion near Portage la Prairie is also expected to be used.

The province says the potential for flooding could change, depending on weather conditions between now and the spring melt.

Workers have completed ice-cutting along the Red and Icelandic rivers to reduce the chance of ice jam-related flooding.

“The run-off potential is significantly affected by the amount of additional snow and spring rains, frost depth at the time of run-off… timing and rate of spring thaw, and the timing of peak flows in Manitoba, the United States, Saskatchewan and Ontario,” the government’s March flood report, released Wednesday, says.

“A late thaw and spring rainstorms could result in a rapid snow melt that increases overland flooding and flows on tributary streams and larger rivers.”

This report by The Canadian Press was first published March 22, 2023