A dramatic night of storms in Toronto on Wednesday flooded subway stations, turned a major freeway into a river and knocked out power to thousands of people.
On Wednesday, Environment Canada issued a special weather warning for heavy rain in Toronto Wednesday evening. Some parts of the city received nearly three inches of rain in just three hours.
Large sections of the Don Valley Parkway, a major freeway, were submerged Wednesday evening, and all lanes and ramps were closed for much of the night.
Dozens of people had to be rescued from their cars as water lapped at windows. One driver, who tried to get on the DVP after seeing that his normal route home from work was closed, told the Toronto Star, that his car died just moments after he noticed water under his tires.
“When you’re in it, it’s too late, it’s way too late,” the driver, Len Lal, said.
Water was up to Lal’s waist in the car before he was rescued. “It’s like a scene out of Terminator: Salvation,” Lal said after his rescue.
Fire crews on Wednesday night also helped rescue 12 kayakers from the Humber River after they were caught out in the storm and lost contact with their guide.
While the skies were mostly clear in Toronto, Thursday morning, there is still a 40 percent chance of more rain. People are being advised to stay away from rivers, lakes, and other bodies of water which may still rise and service on some rail lines remains disrupted.
If summer flooding in Toronto sounds familiar, it’s because nearly one year ago, the city was slammed by a storm that dumped a month’s worth of rain in two hours.
On July 8, 2013, parts of the city disappeared under 126 millimeters (about 5 inches) of rain. The storm knocked out power to 300,000 Toronto residents and 1,400 passengers were stranded for hours on a commuter train filled with water.
The event was pegged as the most expensive natural disaster in Ontario history, by the Insurance Bureau of Canada as insured property damage topped $850 million.
This kind of torrential downpour, where weeks or even a month of rain falls in just a couple of hours has become more common in recent years and is predicted to increase in frequency and intensity as the planet warms. As the world’s oceans and air warm up, more water is transferred from the ocean into the atmosphere. That’s because warmer water leads to more evaporation, and warmer air can hold more water. The air holds about 7 percent more moisture for every 1 degree Celsius increase in temperature. That moisture can then be concentrated into fronts, which unleash torrential downpours when they encounter disturbances in the air or land.
The risk for flash flooding following a heavy rain is greatest in urban areas where the vast majority of surface area is paved over. To respond to this threat, Canada’s largest property and casualty insurance company, Intact Financial Corp, is working with the University of Waterloo to help make cities in Canada more resilient to flash flooding. Work will begin this summer in the Greater Toronto Area and four other cities to plant trees and replace concrete and asphalt surfaces with vegetation and permeable surfaces that absorb water.
The Insurance Bureau of Canada says claims related to catastrophic weather events have surpassed $1 billion in every year since 2009.