Manitoba Transportation and Infrastructure has issued a flood warning for the Assiniboine River from St. Lazare to Griswold.

The Shellmouth Dam is being operated to reduce the risk of flooding downstream on the Assiniboine River while at the same time providing sufficient storage for water supply. Dam operations are constantly assessed and outflows may change as melting and run-off in the upper Assiniboine River basin resumes.

An overland flood warning is still in effect for southern Manitoba from the Saskatchewan border eastward to Provincial Trunk Highway (PTH) 12 and from the United States border northwards to PTH 1, extending north of PTH 1 between PTH 5 and PTH 16, and north of PTH 1 between Portage la Prairie and Winnipeg. A high water advisory has also been issued for the Whiteshell lakes area as levels on most lakes continue to rise due to rainfall and snowmelt.

Water levels on most tributaries in the Red River basin are at peak and staying steady or slowly declining after two days of rapid increases. River levels on the Red River continue to increase but the rate of increase has slowed significantly compared to the water level increases experienced over the week. Daily average temperatures are expected to increase to above zero by mid-week.

Southern Manitoba basins, including the United States’ portions of the Red, Souris, Pembina and Roseau river basins, have received an average of 60 millimetres of precipitation since April 22.

Flood forecasters will continue to monitor precipitation amounts and assess impacts on flows and levels.


For more information about flooding in Manitoba, visit