"Ontario saved money on the winter maintenance of provincial highways over the last five years, but at a cost that included greater delays in clearing highways so that they were safe to drive during and after a storm," Lysyk said in a special report.
"We can't help but think the negative consequences of the changes made five years ago to performance-based contracts might have been foreseeable and avoidable."
Prior to the contract changes in 2009, Ontario's most travelled highways were cleared about 2.1 hours after a storm, but that had increased to an average of 4.7 hours by 2013-14.
"It is often taking contractors twice as long to clear a highway down to bare pavement after a storm than Ontarians were used to," said Lysyk.
The contract changes put more emphasis on the lowest bidder and less on a company's ability to actually do the job of clearing snow from roads and highways.
"The 'weighting' of whether a contractor had enough equipment or not was only 15 per cent of the whole picture," said Lysyk. "They could pass stage one even if they had zero points associated with equipment, and they got into stage two, which was just based on costs."
Ministry of Transportation staff warned the government that some of the contractors didn't have the equipment needed to clear the highways as promised, said Lysyk.
"The contracts were awarded when the contractors provided assurances they would be able to do the work as expected," she said. "This was not the case, and the Ministry has had to ... provide additional funding for equipment and highway treatment materials."
Contractors started using less salt, sand and anti-icing liquids on highways, which they patrolled less often than before the contract changes, added Lysyk.
"Some contractors eliminated the use of anti-icing liquids all together," she said.
Six of the 20 contractors did not even meet the province's "generous" standard of clearing the highways of snow within eight hours 90 per cent of the time.
Winter road contractors faced $13.3 million in fines in 2013-14 for failing to meet targets, but the government waived $4.8 million of the fines, in some cases so the contractor would buy more equipment to clear highways.
Transportation Minister Steven Del Duca said the government did an internal review on winter road contracts and would implement the auditor's recommendations.
"Let me assure all of you, we will take action, and we will get it right," he said.
The Opposition said the Liberals should have acted much sooner to correct a problem they created with their 2009 change to performance-based contracts.
"The auditor's report is a damning indictment of a government that has placed cost savings over the safety of Ontario motorists," said Progressive Conservative transportation critic Michael Harris.
The New Democrats said they have no confidence highways will be any better next winter because the same road maintenance contracts remain in place.
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