TORONTO -- Many Ontarians who rely on natural gas to heat their homes will find themselves shelling out a lot more.

Enbridge Gas Distribution Inc. says the Ontario Energy Board has approved new rates effective April 1.

The increase means nearly $400 over the next year for the average Enbridge customer, who normally would pay roughly $1,000 annually for natural gas.

Enbridge (TSX:ENB) says the OEB's approval is on an interim basis while the board considers steps to smooth costs for customers.

Enbridge applied for the increase earlier this month, a few weeks after predicting that its massive storage capacity should mute any price increase.

But the utility says it was forced to buy more natural gas -- at a much higher cost -- than expected and it must recover those costs.

"We respect the decision and the interim order of the Ontario Energy Board and its desire to further review the bill impact on customers following our coldest winter in 25 years," Malini Giridhar, the vice president of Enbridge Gas Distribution said in a statement.

Former Liberal MP and energy market watcher Dan McTeague has predicted the price hike will work out to $500 dollars once taxes are factored in.

Enbridge says the full effect of the increase is not expected to be felt by most homeowners until next winter.

Other gas utilities in central Canada are expected to follow suit.

Households heating with propane and oil have already experienced a price shock this winter.

Propane customers in eastern Ontario and western Quebec saw their home heating bills nearly double in January and February compared with what they were paying in November.