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Canadian Urbanism Uncovered

A-salting the Earth

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It's almost impossible to make plans with my dad in the winter. His rural sensibilities dictate that as soon as the first snowflake of the season touches the ground, driving conditions are unpredictable. No matter how far ahead you plan, or how important the event you're planning may be, his reply to any invite remains frustratingly consistent: "We'll have to see what the weather's like," he says. "You never know if they'll be calling for freezing rain."

This attitude towards winter driving is rare in Toronto. The nation's economic engine can't afford to let nature get in the way of people getting where they want when they want as quickly as possible, no matter the weather conditions. To be fair, this attitude is common in many places throughout Canada. And the use of road salt has helped make it possible.

"We only started using salt [on roads] in the late '40s, early '50s," says Kevin Mercer, founding executive director of RiverSides Stewardship Alliance, "but we're making up for lost time."

Unfortunately, too much salt in the ecosystem is about as devastating to our environment as eating fries day after day is to our bodies. In 2001, the federal government released a report deeming road salt environmentally toxic. It may keep cars from slipping all over the road by lowering the freezing point of water, but it also seeps into our water table, dehydrates our trees, and poisons our wildlife and aquatic life. What's more, it causes costly damage to our infrastructure, corroding our roadways, sidewalks, and vehicles.

At the heart of the problem is a little rule in Ontario's Environmental Protection Act called Regulation 339. Normally, anyone wanting to use a toxic substance would have to be issued a Certificate of Approval from the Ministry of the Environment. Road authorities are exempt from this rule, however, if the toxic substance is being used to keep highways safe from the dangers of snow and ice.

"If you wanted to use nuclear waste to keep roads clean, that regulation exempts it from the Environmental Protection Act," says Mercer. "Road safety trumps the environment."

In 2003, 6.8 million tonnes of road salt was sold for highway de-icing in Canada, while Toronto uses 130,000 to 150,000 tonnes of salt annually. The frightening thing is, salt doesn't break down — once it leaves the salt trucks, it's in our environment to stay. In a densely packed city like Toronto, the salt becomes particularly concentrated.

"Fifty percent of it winds up in our ground water table," Mercer says.

While freshwater normally contains between 20 and 50 milligrams per litre, the average river or stream in Toronto contains 300 to 1000 milligrams of salt per litre. Road salt finds it way into rivers and lakes by running into stormwater sewers and by seeping into our ground water (unless it becomes attached to plants or soil first). Ravines have typically been popular sites to dump snow that has been cleared off roadway. Such snow is usually laden with salt, which can easily wash into a nearby river, contaminating our water supply and poisoning aquatic life.

The way salt is stored can also cause problems. "You used to be able to go down to the Port Lands and see a big white pile of salt. When it rained, it would go into the lake," Mercer says. "I can only imagine what the chloride levels were in the harbour during that time."

Thankfully, at the City level, things have been changing. Toronto is the first city in Canada to have a salt management plan. Released in 2004, the plan includes annual inspections of salt storage facilities, the upgrading of trucks so that salt is spread more efficiently, and a review of snow disposal sites.

But Mercer says that both the provincial and federal governments need to do more to ensure that road salt is used safely and sparingly. In a report on road salt released in February 2006, RiverSides, along with the Sierra Legal Defence Fund, called for the Province to repeal regulation 339 and implement mandatory regulations for the use, storage, and disposal of salt-laden snow. The regulations would require road authorities obtain a certificate of approval before road salt can be used.

The report also advocates for changes that would affect the way individuals approach winter driving. "Make snow tires mandatory," says Mercer, who helped research and write the report. "It's simple! Then you won't have people sliding all over the place." He says the province should also lower speed limits during winter conditions, which could mean big changes to our hustle-and-bustle lifestyle. Clearly, a balance needs to be struck between our short-term and long-term safety. "As a society, we believe that we have to prepare for catastrophes," says Mercer, referring to the fear that without road salt car accidents will rise, "meanwhile, death by a thousand cuts happens all the time."