Residents, cottage and business owners on some of the biggest lakes in Muskoka are launching a $900-million class-action suit against the Ontario government because of flooding caused by high water levels.

People living on Lake Muskoka, Lake Joseph and Lake Rosseau say they suffered extensive damage during this year’s spring thaw because of high water and drifting ice that wreaked havoc on docks, boat houses and their properties.

The Ministry of Natural Resources is responsible for controlling the water levels in the lakes, and the residents blame poor management and negligence for allowing the water levels to become dangerous.

The Ministry says it’s sympathetic but points out severe weather conditions are out of its control and notes the spring melt was earlier and faster than normal this year.

Lawyer Troy Lehman says the extent of the damage is “enormous” but the actual cost of repairs is still unknown, and most residents have not been successful in making insurance claims.

Peter Burgess, the representative plaintiff in the proposed class-action suit, which has not been certified by the courts, says it’s frustrating to suffer widespread property damage and not be able to afford to fix it.

Cassandra Ford, who operates a marina and restaurant in Bala, says she is looking at up to $400,000 to rebuild a damaged boathouse.

Ford says she wants the ministry to explain why there was no flooding for 60 years and then three major floods since 2010.

“Nobody seems to care,” she said. “They don’t care.”

In addition to monetary damages, the suit also aims to secure a judge’s order that would force the ministry to address the issue and maintain safe water levels.