The basics of flood risk

Flood risk is based on a combination of hazard, exposure and vulnerability.

• Hazard means natural factors that are out of our control. This includes heavy rainfall, storm surge and rising water levels.
• Exposure means what parts of our communities, like people, structures, infrastructure and ecosystems are in the hazard area.
• Vulnerability means the specific characteristics of an area that make it more sensitive to flood damage.

We can better understand the hazard by studying how often floods have occurred in the past and how these conditions will change in the future. We can estimate when and where floods could occur and what conditions will look like.

We have no control over the hazard as we cannot change the weather. Instead, we can manage our exposure and our vulnerability.

We can reduce exposure by keeping structures and people away from flood hazards. This includes building further away from the coast and floodplains. The flood modelling shown on this website can be used to understand high level exposure to flooding across the municipality. 

Reducing vulnerability is how we can protect the people, places, and services that are most at risk. This includes actions like:

• prioritizing flood protection for critical infrastructure and vulnerable populations, like hospitals and long-term care homes;
• expanding green spaces to absorb and store water;
• upgrading stormwater infrastructure to handle more intense rainfall; and
• making plans and strategies before a flood happens to keep people safe.

For more information on reducing vulnerability, see what can be done, get flood ready and FloodSmart Canada.