The city of Saskatoon was one of the hardest hit areas when nasty storms cut across much of Alberta and Saskatchewan overnight Tuesday.
City officials said Saskatoon received 80 millimetres of rain in three hours and some parts may have been inundated with more than 100 millimetres.
Crews were busy Wednesday dealing with flooded streets and basements, and some streets were blocked off so vehicles didn't get caught under water.
The city's fire service had to respond to dozens of calls of downed trees and power lines, cars stuck in intersections and alarm systems going off.
Mayor Don Atchison said workers were doing everything they could.
"Our first concern was for the safety of the residents, making sure we have the streets blocked and that, so vehicles weren't travelling through them," he said. "In fact, there is the odd vehicle out there right now that was submerged ... (and) that'll be dealt with."
"The water is going down right now, but still there's a lot of work that's going to have to be done over the next few days."
The city was urging residents to avoid using large amounts of water to avoid overloading sanitary sewer systems. Sewage storage superpipes were filled to capacity by the storm and overflowed through manholes. Special ponds built to try to alleviate flooding couldn't take all the rain.
"The ponds that we had are overflowing with water right now," the mayor said. "This could certainly be classified as one of those one-in-100-year floods - if not more - that we've had in the west end of the city."
"We're just checking other areas right now to make sure that things are fine."
Hail, lightning, intense rain, high winds and funnel clouds were all part of the storm system that swept through the two provinces.
In Alberta, there were reports of hail as far south as Lethbridge and as far north as Fort McMurray.
Environment Canada confirmed there was a tornado 30 kilometres near Whitecourt, northwest of Edmonton, but it wasn't known if there was any damage.
Edmonton fire crews were called to a report of lightning striking a home and causing a small blaze, but there were no injuries and the fire was quickly extinguished.