Low-income residents, visible minorities disproportionately affected by flooding risks in Canada: study

Homes are surrounded by the flood waters on Riverside Drive in Fredericton on Monday April 22, 2019. (THE CANADIAN PRESS/Stephen MacGillivray)

While climate change is affecting the entire globe, experts have emphasized that its detrimental impacts fall more heavily on some groups than others — an observation underlined by a new study that has found socially vulnerable groups in Canada are more likely to be impacted by flooding.

The study, published in July in the peer-reviewed journal Environmental Research, looked at data on regions across Canada that are at a risk of flooding and cross-referenced these with census information on demographics and census boundaries to create a picture of the most flood-prone neighbourhoods, as well as who lives within them.

They found that socially disadvantaged groups in Canada, including Indigenous people, other visible minorities, the economically insecure, women and those aged 65 years and older, were disproportionately affected by coastal and inland flooding.

"This research fills the gap of analyzing and addressing flood-related socio-economic discriminations while considering divisibility aspects of flood hazards and contributes to the emergent and quantitative environmental justice literature on flood-related socio-economic disparities," Liton Chakraborty, a researcher with the University of Waterloo’s Partners for Action, and lead author of the study, said in a press release Monday.

The study looked at 4,458 census tracts (CTs) across the country — a term that refers to a region that usually has a population between 2,500 and 8,000 persons and has been delineated as a region for census purposes.

Within these CTs, they looked at how many residential properties were exposed to flooding risks based on rainfall, coastal flooding and river flooding.

When they isolated the differing causes behind flooding, they found that regions at a higher risk of specifically rainfall-caused flooding also had higher populations of Black and Indigenous people and other visible racial minorities.

Researchers say this is the first study to look broadly at whether minorities in Canada suffer higher flooding risks, and they believe this data could help guide resources for mitigating those risks.

"Our research shows how the spatially varying distribution of flood hazards and socio-economic deprivation, or social vulnerability indicators, could inform Canada's equitable flood management approach that complements the federal government's Gender-based Analysis Plus priorities in flood-related disaster and emergency management policies across Canada," Chakraborty said, referring to a federal analytical process that assesses how environmental policies can maximize benefits for demographics most impacted by climate change.

"Therefore, the paper's findings promote a socially just flood risk management approach emphasizing the need to acknowledge socio-economic heterogeneity within various racial, ethnic, and socio-demographic groups.”

The study follows up on previous research by Chakraborty published in January, which found that socio-economic vulnerabilities within Indigenous communities in Canada meant greater hardship in the event of a flood.

The January study found there were “hotspots” where flood risk correlated with serious socio-economic disadvantages, and that 81 per cent of the 985 Indigenous land reserves included in the study had some regions where flooding would impact population or residential properties.

Measuring flooding risks is likely to become even more important as time goes on, experts say, as climate change marches on.

A California study published earlier this month found that climate change had already doubled the likelihood of a massive storm striking the U.S. state and causing catastrophic damage, stating the potential flooding could be of “biblical” levels.

Previous research from the University of Waterloo has also shown that human activities are increasing flood risks outside of our contributions to climate change as well. A study published in March found that rivers or streams managed by human interventions such as dams, canals, or diversions for urban buildings had more flow fluctuation compared to rivers unaltered by humans.

This most recent study on flooding risks and socio-economic status also echoes broader research that has suggested those who live in areas with a higher risk for climate-change-caused extreme weather are more likely to have less resources and already be marginalized in society.

One 2021 study found that Canadians from racialized and lower-income families were disproportionately affected by sizzling heat compared to wealthier, predominantly white neighbourhoods. It was noted that those who are already disadvantaged by society are less likely to be able to move, or to pay for renovations that could make their houses cooler, and that poorer neighbourhoods often receive less investments from their cities in terms of green spaces and trees that lower overall heat.

Researchers are hoping this new study on flooding risks will prompt more investigations.

“The study emphasizes the quest for the most appropriate methodological framework to analyze flood-related socio-economic inequities in Canada,” researchers wrote.