John Pomeroy, the Canada Research Chair in Water Resources and Climate Change, says rainstorms in late June started the overland floods in southeast Saskatchewan and southwest Manitoba and raised levels in waterways such as the Assiniboine River.
"This sort of flooding is absolutely unprecedented. Normal prairie flooding is due to snow melt and it occurs in April and a little bit into May," said Pomeroy, who is also the director of the Centre for Hydrology at the University of Saskatchewan.
"To have one start off completely due to rainfall and start in June and move into July is something we've never seen before; there are no records of this type of flooding ever occurring here," he said in an interview Thursday.
But while heavy rainfall amounts caused overland flooding and raised water levels along the Assiniboine River and other waterways, Pomeroy said it's not the only factor.
"The drainage of natural prairie wetlands by farmers throughout the Assiniboine River and Souris River basins has likely substantially increased the flood peaks and the volume of flow that's coming down in towards the Assiniboine River right now," he said.
Pomeroy said the issue of wetland drainage should be seriously considered "as we start to look at perhaps increased incidents of high summer rains like this.
"Can we do something about it? Well, maybe the first thing is to stop draining wetlands."
Click on the video above to watch the full interview.