Backgrounder: Floods

Impacts of floods in Canada

Flooding is Canada's most common and costly disaster and can happen anywhere in Canada at any time of year. Many parts of Canada's biggest cities – including Vancouver, Calgary, Edmonton, Toronto, Montreal, Ottawa-Gatineau and Fredericton – are located in high-risk flood areas.

Canadian cities located along rivers and lakes commonly experience riverine (fluvial) flooding, but flooding can be triggered by many other situations, including heavy rainfall, snowmelt runoff, ice jams, natural or man-made dam failures, and coastal storms.

Coastal communities are particularly at risk from storm surge and waves/tides that flood roads and highways, isolating many small and remote Indigenous communities. As we saw with Hurricane Fiona, coastal storms also cause significant damage to infrastructure like ports, harbors and marinas, and can result in disruptions to coastal supply chains and trade, creating an estimated annual cost of between $4-$17 billion^{Footnote 1}. As sea levels rise and rainfall increases, flood damage to homes and buildings across Canada could increase fivefold in the next few decades and by a factor of 10 by the end of the century, with costs as high as $13.6 billion annually^{Footnote 2}.

The National Risk Profile's findings on floods

The National Risk Profile found that many factors are increasing the risk of flooding in Canada:

• Climate change is expected to impact flooding differently across the country, due to  changes in precipitation, snow and ice melt, and water levels;
• Increased urbanization is leading to more impermeable surfaces like parking lots which is disrupting natural drainage systems; and
• In some cases, infrastructure continues to be built on flood plains.

The report highlights direct and indirect human impacts of floods. During a flood and in the weeks following a flood, critical infrastructure like health care facilities or power grids can be cut-off, while roads and highways, bridges, railways, airports can become impassible or inaccessible.

Floods can have direct impacts on the physical and mental health of individuals and communities, potentially causing health effects, like respiratory illnesses, from increase contact with mold, viruses or bacteria. After a flood event, stress, anxiety, traumas and a reduced sense of security are all common. Floods present indirect health impacts to communities or regions by redirecting or interrupting health care services during the flood and during the time it takes to recover.

The report found that there are gaps in Canada's flood resilience around coordination of flood risk management between levels of government, availability of accessible and affordable flood insurance, and Canadians' awareness of their personal flood risk.

Canada's flood risk reduction plans and actions

In Canada, the responsibility for managing flood risk is shared between all levels of government, industry sectors, non-government organizations, communities and individuals. The federal government's primary role in flood risk management is to coordinate with, and support, provincial, territorial, and local efforts to mitigate, prepare for, respond to, and recover from flood emergencies.

Efforts are underway to build a consistent national understanding of floods through developing Federal Flood Mapping Guidelines.

Work is also underway to create a nation-wide flood risk awareness digital resource that gives Canadians the flood risk information they need and information on how best to protect their homes and communities. Budget 2023 proposes an additional $15.3 million over three years to continue this work.

The digital resource will use flood hazard modelling data, licensed through funding made available by the Flood Hazard Identification and Mapping Program (FHIMP). The resource will provide a consistent understanding of flood hazard across the country, and will also provide links to existing local flood maps where available.

The National Adaptation Strategy proposes expanding the FHIMP to 2028, with over $160 million in new funding. The program helps provinces and territories develop authoritative flood hazard maps to inform decision-making in support of flood mitigation, climate adaptation initiatives, and in building resilient infrastructure.

The Government of Canada also hosts an Emergency Geomatics Service, which provides near-real time flood extent maps from satellite data. These maps track active flooding events in Canada and provide crucial and timely information to emergency responders, evacuation managers, and community members.

Budget 2023 proposes $31.7 million to stand-up a low-cost flood insurance program, aimed at protecting households at high risk of flooding and without access to adequate insurance. This includes offering reinsurance through a federal Crown corporation and a separate insurance subsidy program.

The Government of Canada is committed to ensuring that Indigenous perspectives are included in flood risk management by engaging Indigenous partners in the Steering Committee on First Nations Home Flood Insurance Needs (PDF)^{Footnote 3}, and through extensive engagement within the Flood Insurance and Relocation Project.

The Government of Canada is also reviewing the Disaster Financial Assistance Arrangements and proposes $48.1 million over five years and $3.1 million ongoing to identify high-risk flood areas and implement a modernized Disaster Financial Assistance Arrangements program, which would encourage proactive mitigation measures before an emergency or disaster occurs to eliminate or reduce the impacts of disasters on our communities. This will ensure the program continues to be a relevant, effective and sustainable instrument for supporting all Canadians, through provinces and territories, after extraordinary disaster events.

Date modified:

2024-12-06