About 340,000 properties, or 20 per cent of the population, are exposed to some degree of flooding, the Insurance Bureau of Canada's Quebec branch says.

Desjardins Group announced as of Feb. 1 it would no longer offer new mortgages for properties in “0-20 year” flood zones — where there is a five per cent chance of flooding in any given year — because of what it called the rising effect of climate change.

There are some exceptions: buyers can get financing for up to 65 per cent a home’s selling price if the previous owner had a Desjardins mortgage and the property has protective measures to prevent flooding. But the company’s decision has left mayors of low-lying towns worried that homeowners will be left with properties that no one will buy or that are massively devalued.