The top cities in Ontario for flood risk

Some of Ontario’s most-populous cities are at the highest risk of flood, and not all their resilience projects are keeping up, a new report finds. 

Ajax, Ottawa, Mississauga, and Toronto top the province’s list of the most flood-prone areas, finds the analysis by MyChoice Financial. 

“These cities are characterized by dense populations, extensive infrastructure, and increasing urbanization — factors that exacerbate their flood vulnerability.” 

The analysis combined critical factors like annual rainfall, distance from lakes or rivers, drainage density, land use, terrain types, and urban infrastructure, to develop a score system from one to five for each of the top 20 cities for flood risk. Ajax (4.6), Ottawa (4.5), Mississauga (4.4) and Toronto (4.3) scored the highest. 

There’s a significant concentration of flood risk in the Greater Toronto Area and Eastern Ontario — two of the top densely populated regions in the province, the study finds.  

Related: Industry estimates price tag for Ontario’s July flooding

But other cities like Brampton (4.3), Brantford (4.2), Vaughan (4.2), and Sarnia (4.1) also scored highly, showing flood risk is widespread across the province. 

The Windsor-Essex regions (Windsor, LaSalle, Lakeshore) all scored as mid- to lower-end flood risks compared to the GTA and Eastern Canada.  

Of the 20 cities analyzed, Peterborough scored the lowest (3.3). 

Although some of the highest-risk cities are also receiving funding for flood mitigation and defence projects, there are “areas where the response could be more assertive,” MyChoice writes.  

Toronto’s total cost of climate resilience infrastructure projects tallies $560 million, to be completed by 2032 — the most of any city. That’s followed by York ($251 million by 2028), and Windsor ($162 million by 2032).

And yet, Windsor has the second-lowest major flood risk score in the MyChoice study, while York doesn’t make list at all.  

On the other hand, “regions like Ajax and Brampton, which have been identified as highly vulnerable, do not appear to receive the same level of investment at the moment,” MyChoice writes.  

Brampton scores as the province’s fifth-highest risk for flood, although it has invested only $97 million in its climate resilience infrastructure projects by 2028. MyChoice says its investment spending on flood resilience is disproportionate to its level of risk. 

Ajax has only dedicated $750,000 to climate resilience, yet it ranks as the province’s top city for flood risk.  

“This suggests that while the government’s response is generally in line with the identified risks, there may be gaps that need addressing to ensure comprehensive flood protection across all high-risk areas.” 

 

Feature image by iStock.com/Marc Bruxelle