What is overland flooding?


Overland flooding, where water flows overland and seeps into buildings through windows, doors and cracks, is one of the most frequent and costly natural hazards in Canada. Floods have affected hundreds of thousands of Canadians and cause millions of dollars in damages each year.

Floods can occur in any region of Canada, at any time of the year, but most flooding occurs when the volume of water in a river or stream exceeds the capacity of the channel. Flooding also takes place along lake and coastal shorelines, when higher than normal water levels inundate low-lying areas.

Heavy rainfall can lead to flooding, especially in the spring, when the ground is still frozen or already saturated from previous storms. Rapid melting of snow and ice jams can also lead to floods. Flash—or sudden—flooding, in which warning time is extremely limited, can result from other causes such as hurricanes or the failure of dams.

The Cost of Flooding

Over the past few decades, urban flooding has been a growing problem, resulting in more than $20 billion in flood damage over the ten-year period between 2003 and 2012. An added concern is that many Canadian homeowners aren't insured for overland flooding, and can be left to deal with replacement of their valuables and expensive repairs.

Your role

Governments may have assistance programs in place to address disasters, but individuals play a crucial role too. We all need to do everything we can to protect our homes and families.

Being Flood Ready can save money, properties and lives.


Did You Know? – Every Canadian river experiences floods at one time or another?

Floods are a natural phenomenon, but the risk of property damage becomes high when development happens in flood-prone areas.

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