A motorist is stranded by storm water that collected under the McPhillips Street underpass Saturday evening. (CBC)More than 500 Winnipeg homes were hit by flooding caused by a weekend of torrential rain many people will only experience once in their lives.

The two storms that roared through the city Saturday caused a once-in-50-year downpour, according to City of Winnipeg officials.

The storms dumped 110 millimetres of rain turning streets and fields into lakes.

'That's like a half-year supply of thunderstorm hours in southern Manitoba.'—Dave Phillips, Environment Canada

Prior to that soaking, the city had only received 48 millimetres of rain in May, according to Environment Canada senior climatologist Dave Phillips.

"Over the weekend, my gosh, I can't believe the number of thunderstorms — Friday, Saturday, 13 hours of thunderstorms — that's like a half-year supply of thunderstorm hours in southern Manitoba," Phillips said.

Calls to the city's 311 service as of noon Monday, show 513 homes experienced soggy basements, according to City of Winnipeg officials.

A tree topped onto a car at Flora Avenue and Parr Street during a thunderstorm Friday in Winnipeg. (CBC)Motorists who had their vehicles damaged during the storms have also begun to file claims with Manitoba Public Insurance.

So far, more than 200 flood-related claims have been filed, said MPI spokesman Brian Smiley.

About half the claims come from Winnipeg, where many vehicles sustained damage after going through underpasses filled with water and becoming partially submerged.

Other vehicles were hit by debris, even trees, tossed about by strong winds.

Claims from outside the city are vehicles damaged because they were parked in low-lying areas and were swamped.

Flooding across city

Calls to the city about flooded basements came from nearly every neighbourhood and are not concentrated in one area, officials said.

"It doesn't make you happy when you see people moving out mattresses and beds to their back yards and having to get pumps to pump out the water," said Mayor Sam Katz, who viewed some of the damage Sunday in the city's Transcona neighbourhood.

"There were some very bad scenarios."

A sign for the golf cart path is nearly submerged on the flooded Transcona golf course Sunday. (Richard Romanow)In addition to seeping into basements, the rain washed debris into streets and clogged drains, which resulted in the development of large pools of water spreading across streets and into yards.

Some roadways were barricaded to keep vehicles from passing through dangerously deep water.

Transcona resident John Tubicz was at a local hardware store at noon Sunday and watched people frantically buy up the stock of pumps to get water out of their basements.

"People were racing to the sump pumps and within seconds the shelf was empty," he said.

He estimates the damage in his basement at a few thousand dollars.

'You know, I can't cry. It's beyond that point.'

—Winnipegger Diane Witwicki

Another city resident, Diane Witwicki, was having trouble comprehending the amount of damage in her home.

"Insulation, the paneling. Everything. The carpeting. You name it. Everything's gone," she said. "Some of it was my mom's — my mom's been dead for 26 years. You know, I can't cry. It's beyond that point."

Problems at the pumps

Some of the problems in South Transcona can be traced back to a problem at the pumping station that serves the area, said Randy Hull, Winnipeg's emergency preparedness coordinator.

"All three pumps at one point had failed. When I visited there about 2:30 a.m. [Monday] they were not operational, but when I went by at 8:30 a.m. they were in operation," he said.

Despite the faulty pumps, the city is not responsible for flooded basements in the area because the storm was an act of God, Hull said.

In Brandon, the thunderstorms did much of the same damage to yards and basements, while also uprooting several trees across the city. Rick Bailey, director of parks and recreation, said the clean-up should take all week.

"[The] soil's just become so saturated, and then when you get that wind that come through, that's where a lot of the trees come over," he said.

The Assiniboine Community College's North Hill campus was badly hit with about 25 toppled trees.

Rising river

The rainfall has also raised the level of the Red River and prompted officials to activate the floodway, a 48-kilometre channel that diverts water around the eastern side of Winnipeg.

Flood Forecaster Alf Warkentin said the Red River in through Winnipeg went up nearly three metres on the weekend and could rise another half-metre by the end of Tuesday.

Most of the tributaries leading into the Red and Assiniboine River have emptied, so the rate of the increase is dropping off.

High river levels in Winnipeg impact the city sewer system's ability to operate at a normal capacity. That means there is an increased risk of basement flooding as the overloaded system backs up through household sewer lines that aren't protected by sump pumps and backwater valves.