The Canadian property and casualty insurance industry has experienced significant losses from basement flooding over the past few years. Specific examples of large loss events include the August 19, 2005 extreme rainfall event in southern Ontario, which resulted in over $500 million in total insurance claims, $247 million of which was attributed to claims from sewer backup in homes. Also in 2005, flooding in southern Alberta resulted in approximately $300 million in insurance payouts, $145 million of which was attributed to sewer backup claims, and Edmonton experienced a sever rainfall event that resulted in $143 million in sewer backup claims in July, 2004.

The weather system that caused flooding in Edmonton in early July 2004 later swung around Canada and combined with another system to cause extreme rainfall in Peterborough, Ontario, resulting in over $87 million in insurance claims.

The Insurance Bureau of Canada has estimated that water damages cost insurers $1.7 billion per year, and claims from basement flooding comprise a significant portion of this figure. Insurers have begun to address the issues of basement flooding through several approaches, including funding research on basement flood risk identification and risk mitigation, and incentivizing risk reduction measures by homeowners.

Handbook for reducing basement flooding

 

Current list of Canadian municipal subsidy and loan programs for basement flood risk reduction