Treading Water: Impact of Catastrophic Flooding on Canada’s Housing Market

Project overview

Cities and communities included in the study shared at least 2 of the following characteristics:  

• experienced insurance claims post-flood event > $25 million
• magnitude of flooding > 1-in-50 year event, for example a major flood
• the community did not have a history of repeated catastrophic flooding

5 cities met the above criteria and were considered in the real estate component of the study:

• Grand Forks, British Columbia
• Burlington, Ontario
• Toronto, Ontario
• Ottawa, Ontario
• Gatineau, Québec

The impact of flooding on the real estate and mortgage markets was measured for periods of 6 months pre- versus post-catastrophic flood event.

The "net effect" of flooding was determined by "subtracting" changes in the variables under consideration in non-flooded control communities.

Key findings

The net impacts of catastrophic flooding on residential housing were:

• 8.2% reduction in the final sale price of a home
• 19.8% more days on market to sell a home
• 44.3% reduction in the number of homes listed for sale

In contrast to the substantial impacts of flooding on multiple characteristics of the real estate market, there was no material impact on mortgage arrears and deferrals.

Mitigating residential flood risk

Suggested actions to help limit the impact of flooding at the community and/or home levels include:

• Home Flood Protection Guidance
• Climate Adaptation Home Rating Program (CAHRP)
• Flood Risk Maps
• Residential Flood Risk Scores
• Natural Infrastructure
• Community Flood Risk Mitigation

For more information, download the full report.

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