Emergency officials are moving people out of the village of Cumberland House and the Cumberland House Cree Nation, and are warning that people could be out for a couple of weeks.
"The water is going to rise, the Water Security Agency indicates, to a level that has been unprecedented in the community — higher than in 2011, which was pretty high," Saskatchewan's deputy emergency management commissioner Colin King said Saturday.
"Therefore, they're going to look at their old plans and where the community is at risk from rising waters and put things like sandbag walls, Hesco barriers, and see what they can protect."
Evacuees from Cumberland House will be taken to hotels in Prince Albert and Saskatoon, and possibly Regina if necessary.
The communities are downstream of where the North and South Saskatchewan Rivers meet and those rivers are swollen as floodwaters from Alberta head east.
The Saskatchewan Water Security Agency says inflows on the South Saskatchewan River into Lake Diefenbaker are expected to be the highest ever recorded. The agency expects more than 6,000 cubic metres per second will arrive on the river — far surpassing typical flows of about 500 cubic metres per second.
The agency says it's going to have to let more water out of the Lake Diefenbaker reservoir. Releases have been increased from 800 cubic metres per second to 2,000 cubic metres per second.
"Two-thousand cubic metres per second is the most we've ever let out," said agency spokesman Patrick Boyle.
The South Saskatchewan River is expected to rise two metres.
Most other communities along the South Saskatchewan River, including the city of Saskatoon, are situated higher on the river banks, so they're expected to stay dry.
However, agriculture land along the river could be swamped and some farmers are concerned.
Boyle said the Water Security Agency has to make space in Lake Diefenbaker because there's more rainfall in Alberta, which likely means there more water to come. He says the water has to go somewhere.
"Ultimately, we're looking at the highest inflow ever into Lake Diefenbaker and that's what we're trying to deal with here. We never want to flood out anyone ... we're trying to mitigate that as much as possible," said Boyle.
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