海角社区官网simply wasn鈥檛 built to withstand weather events like Tuesday鈥檚 sudden, torrential downpour 鈥 even though they鈥檙e becoming far more common.
That was the message the city鈥檚 top civil servant gave reporters as emergency crews worked frantically to resolve power and transit outages across the city, homeowners confronted widespread property damage 鈥 and rain leaked through the ceiling at City Hall.
While the city has invested in flood mitigation measures in response to climate change 鈥 and those efforts have delivered some results 鈥 鈥渢he reality is these storms come in greater frequency. They鈥檙e happening,鈥 Paul Johnson said. And 罢辞谤辞苍迟辞鈥檚 鈥渋nfrastructure was not designed to handle this.鈥
Environment Canada is calling for up to 125 mm of rain on Tuesday. There may be 40 mm of rainfall per hour.
A little over 97 millimetres of rain were reported at Pearson International Airport by late Tuesday late afternoon 鈥 the fifth wettest day ever recorded there, with a chance of further showers later in the evening.
While that remains shy of 罢辞谤辞苍迟辞鈥檚 single-day rainfall record, 鈥渨hat really shocked me was the intensity,鈥 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. 鈥淭he city is just not able to cope with this new reality,鈥 he added. While no one has done an attribution study yet to tease out climate change鈥檚 responsibility for this specific event, he noted, 鈥渢his wasn鈥檛 a garden variety thunderstorm.鈥
Floods caused chaos across the city, shutting down transit stations, crippling the power grid and stranding drivers on roadways that suddenly turned into rivers.
At one point Tuesday afternoon, 海角社区官网Hydro reported about 170,000 customers without power. Although most hydro stations were back online by 6:30 p.m., one in the west end was still flooded and being pumped out, with no estimate for when service would be restored.
There were incredible scenes on the flooded Don Valley Parkway, where emergency crews rescued about a dozen people from their cars. Firefighters lashed themselves to the guard rail with knotted ropes, to prevent themselves from being ripped away by the current while they freed people from trapped vehicles.
Deputy Fire Chief Jim Jessop told reporters at city hall that 海角社区官网Fire鈥檚 call volume was triple its normal hourly rate, and the service was rescuing people from cars and elevators.
The lower level of Union Station was flooded, blocking access to the GO Transit platform and the food court. Subway trains temporarily bypassed the TTC鈥檚 Christie, St. Patrick, Lawrence and Pape stations, and power outages stopped service on portions of Line 1 and 2.
A security guard directs people how to get to the TTC after flooding affected some of the lower levels of Union station.
Nick Lachance/海角社区官网Star海角社区官网Fire Services reported fielding 1,700 calls, responding to almost 500 incidents between 6 a.m. and 3 p.m. More than 50 were to rescue people from elevators; the city reported more than 700 rain-related calls to 311 for basement flooding.听
Meanwhile, the Ashbridges Bay and Humber water treatment plants faced surges, forcing them to discharge partially treated sewage.
Not even City Hall was spared. Water cascaded several storeys down an interior stairwell on the building鈥檚 northwest side, and recycling bins were repurposed as rain barrels outside councillors鈥 offices on the second floor. The ceiling of one office partially collapsed.
Parthi Kandavel (Ward 20, Scarborough Southwest) said no one was hurt in the incident, but the state of 罢辞谤辞苍迟辞鈥檚 seat of government was 鈥渟ymbolic of the challenges of our city, infrastructure-wise.鈥
In an update to the media at around 4:30 p.m. Johnson, the city manager, said it could take hours if not days, to fix what the deluge broke.
Once the DVP drains, crews would need up to four hours to clear debris from the road, Johnson said, and that鈥檚 assuming there isn鈥檛 more complex damage hiding beneath the water. Flooding at low-lying parks and the 海角社区官网Island wasn鈥檛 expected to recede until later this week.听
鈥淲e鈥檒l get through this and clean up as best we can,鈥 Johnson said.
罢辞谤辞苍迟辞鈥檚 , when 126 millimetres fell at Pearson Airport. That storm caused almost $1 billion in insured damages, and prompted more than 4,700 flooding complaints.
Just five years later, another significant rainfall event, in August 2018, resulted in a further $80 million in insured damages. Both storms, at times, registered rainfall that would classify them as 鈥100-year storms鈥 鈥 so intense that they have a one per cent chance of occurring in any given year.
Officials at the 海角社区官网and Region Conservation Authority said Tuesday鈥檚 storm may have met that threshold, but they still need to verify the rainfall measurements.
Regardless, studies from around the world have consistently shown that climate change is increasing the odds of super-intense rainfall events as a warmer atmosphere holds more moisture.
鈥淔or Canada specifically, the projections clearly show an increase in the most intense rainfall,鈥 said Nathan Gillett, a research scientist at Environment and Climate Change Canada.
Urban flooding is also projected to increase due to the combination of intense rainfall and changes to the built environment. As impermeable surfaces like concrete and asphalt multiply, water runoff finds fewer places to absorb harmlessly back into the ground, overwhelming aging sewers and other infrastructure in a rushing torrent.听
The effects of Tuesday鈥檚 storm were exacerbated by several strong rainfalls in the week before 鈥 when the really extreme weather hit, our systems were already at or beyond capacity.听
鈥淲hen there are multiple catastrophic rains in a row, the ground gets saturated and the water has nowhere to go, causing widespread flooding,鈥 said Blair Feltmate, Head of the Intact Centre on Climate Adaptation at the University of Waterloo.
鈥淲e鈥檙e also experiencing not just more frequent storm events, but the intensity 鈥 the amount of water falling over a short period of time 鈥 is increasing, too.鈥
Feltmate pointed to data that shows the amount of water that falls during the most severe one per cent of storms has increased by 55 per cent over the last 70 years in the eastern Great Lakes region.
鈥淧eople need to realize that climate change is here to stay, period. We鈥檙e not going backwards,鈥 he said.
A number of motorists were stranded as the DVP was swallowed by the rising Don River.
Richard Lautens 海角社区官网StarAlthough the discussion around climate change has focused on reducing emissions, experts say storms like Tuesday鈥檚 demonstrate the urgent need to reinforce homes and cities to withstand future weather events.听
Whether it鈥檚 or maximizing water-permeable surfaces across the GTA, there are simple solutions that need to be prioritized, Feltmate said. 鈥淲e need to adapt and to adapt rapidly.鈥
Mayor Olivia Chow said told reporters the city needs to get serious about addressing the impacts of climate change.听
鈥淚t鈥檚 real,鈥 she said. 鈥淪o we have to redouble our efforts to have mitigating actions.鈥澛
She said that the city is investing in upgrades to its aging infrastructure, including using $2 billion from the upload of the Gardiner Expressway and DVP to invest in the TTC, municipal buildings, the Broadview eastern flood protection and other projects.
Chow said that money 鈥済oes a long way to fixing some of the old infrastructure鈥 but doesn鈥檛 come close to fully covering the city鈥檚 state-of-good-repair backlog of more than $26 billion over ten years.听
Chow said long-term solutions lie in changing the city鈥檚 composition, by swapping out concrete for more porous bricks, for example.
海角社区官网has considered 鈥 and rejected 鈥 strategies to raise money to mitigate flooding damage before. A recent example is the stormwater charge proposal, under which the city would have charged property owners a share of costs to implement flooding prevention infrastructure.听
The amount owed was proposed to be calculated based on the presence of hard surfaces on a property, such as pavement and roofs, which ultimately pour water into public storm drains rather than absorbing them into the ground.
The proposal was lampooned by critics as a 鈥渞ain tax,鈥 however, and Chow paused it in April. Staff are expected to return with a revised proposal, but there鈥檚 no timeline for when they鈥檒l report back.听
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