The massive floods that devastated swaths of southern Alberta inJune are estimated to be the costliest natural disaster in Canadianhistory, with the Insurance Bureau of Canada pegging the propertydamage at C$1.7 billion ($1.65 billion).

The bureau, which represents Canadian home, cars and businessinsurers, said the preliminary estimate for the floods surpassedthe C$1.57 billion in damage caused by the 1998 ice storms inOntario and Quebec.

“It's a staggering number that we expect will go even higher,”Bill Adams, the bureau's vice-president, western and pacific, saidin a statement.

Heavy rains over the eastern slopes of the Rocky Mountains thatbegan in late June caused the 100-year flood that was blamed forfour deaths, forcing the evacuation of thousands and shuttingCalgary's downtown core, the center of the country's oil and gasindustry, for nearly a week.

The preliminary estimate, which will be updated in 60 days, iscalculated from more than 25,000 claims filed to insurers since thefloods.