Road salt is hurting the environment and governments need to find other ways to make Ontario roads safe in the winter, the province's environment commissioner said Tuesday after releasing his annual report.

Gord Miller made his comments the afternoon after salt trucks took to Ontario roads for the third day in a row after the province was walloped by snow for several days.

He said modern technology exists that would work just as effectively as road salt.

A computerized system, already used by the Ministry of Transportation, monitors road temperatures, and allows for road salt to be distributed more efficiently on 20 per cent of Ontario roads.

"They are demonstrating daily that they can reduce the impact and the amount of salt going into the environment,'' Miller told The Canadian Press.

However, municipalities are exempt from the Environmental Protection Act which means they are allowed to blanket road salt on the remaining 80 per cent of provincial roads.

Road salt endangers drinking water, aquatic life and is harmful to plants, the report says.

"The upward trend of road salts usage - as well as the ensuing runoff from roadways, salt storage yards and snow disposal sites - have contributed to elevated chloride levels in surface water, soil and groundwater in Ontario," the report says. "Road salts can contaminate aquifers and compromise drinking water quality for communities relying on well water. Road salts also contaminate soils and damage terrestrial ecosystems.

According to the report, an estimated two million tonnes of road salt is dumped on Ontario roads each year. Urbanization and increased traffic has contributed to the increased usage.

Miller called on the Liberal government to take action, despite the added costs of expanding the computerized system.

"We know there are direct ecological impacts from road salt. Clearly, I think the time is right," Miller said. "(The Liberal government) has the authority, the power to drive this if they choose to."

More money on transit, not highways

The report called on the government to tackle urban sprawl in the Golden Horseshoe region by investing more in public transit rather than spend money on expanding highways.

"The Ontario government's 2007 budget dedicates $6.5 billion to the provincial highway system and $4.5 billion to transit improvements," the report says. "Preventing further infringement on agricultural and green space by road-based transportation will be difficult if the majority of transportation spending continues to be dedicated to highway and road expansion."

The number of people who own a car increases each year in Ontario, according to the report. Currently, there is roughly one car for every two Ontarians, or 48,000 automobiles for every 100,000 residents.

The report singled out a number of highway expansion and construction projects in Southern Ontario and questioned their impact on surrounding green space.

"Without a change in the car-based culture, we are going to see a million more cars trying to use the roads of the Greater Golden Horseshoe and these will only spawn more congestion, more pollution and the unceasing demand for more roads, which will consume even more of the limited green space remaining on this crowded landscape," said Miller.

A spokesperson for the Sierra Club of Canada said problems around road salt and expanding highways are inextricably linked.

"Fewer roads would mean less road salt," said Dan McDermott, with the Sierra Club of Canada. "More transit would mean less road salt."

With files from The Canadian Press