In deep water

A month’s worth of rain in three hours. 1,700 calls for service: 170,000 without power. Toronto wasn’t built to withstand sudden, torrential downpours. And there will be more

- BEN SPURR, KATE ALLEN, MAHDIS HABIBINIA AND BEN COHEN

Toronto Fire Services responded to almost 500 incidents in nine hours, including many stranded motorists on the Don Valley Parkway.

Toronto simply wasn’t built to withstand weather events like Tuesday’s sudden, torrential downpour — even though they’re becoming far more common.

That was the message from the city’s top civil servant as emergency crews worked frantically to resolve power and transit outages across the city, homeowners confronted widespread property damage — and rain leaked through the ceiling at city hall.

While the city has invested in flood mitigation measures in response to climate change — and those efforts have delivered some results — “the reality is these storms come in greater frequency. They’re happening,” Paul Johnson said. And Toronto’s “infrastructure was not designed to handle this.”

A little over 97 millimetres of rain were reported at Pearson International Airport by late Tuesday late afternoon — the fifth wettest day ever recorded there.

While that remains shy of Toronto’s singleday rainfall record, “what really shocked me was the intensity,” said David Phillips, senior climatologist with Environment and Climate Change Canada.

More rain fell in a roughly three-hour period Tuesday morning than a normal amount for the entire month of July, he said.

Climate modelling consistently shows that global warming leads to more intense rainfall, Phillips noted.

“The city is just not able to cope with this new reality,” he added.

While no one has done an attribution study yet to tease out climate change’s responsibility for this specific event, he noted, “this wasn’t a garden variety thunderstorm.”

Floods caused chaos across the city, shutting down transit stations, crippling the power grid and stranding drivers on roadways that suddenly turned into rivers.