In the back of the Agenda for March 6th’s council meeting, there is a section entitled “Payment Vouchers For The Week Ending March 1, 2017,” and in it there’s a figure: “ROAD SALT: $332, 695.15.”
That figure and this article’s headline isn’t a complaint: council is just making sure we don’t slide off the roads — or the occasionally plowed sidewalks — into harm’s way. If they didn’t spend so much money on road salt, we’d damn well blast them for it.
It is a surprising figure, but according to Environment Canada, Canadians spread between 2 – 4 million tonnes of salt across its icy winter wonderland every year. And there is a cost beyond the obvious financial investment in road salt: it ruins more than your dog’s paws and your favourite boots. The stuff erodes roads, cars, and the environment itself.
Its effect on our built environment is simple science: road salt corrodes the rebar in concrete for starters. So we pay money for salt that ensures we’ll later have to pay money for new road and building maintenance. Sounds pretty perfect for sellers of concrete! Repeat business is the best kind. Ditto for plant nurseries selling shrubs:
The corrosive effects of road salt are not overly exaggerated. When the Algo Centre Mall in Ontario collapsed in 2012, road salt was a contributing factor. Same for the deterioration of Montreal’s Champlain Bridge around the same time, which would cost billions to fix. A crown-commissioned report revealed the bridge was not designed to withstand corrosion caused by salt.
So it’s ironic that we use road salt simply because it’s cheap, given the costly damage it does. But in defence of road salt, its cheapness and effectiveness ensures public safety. If municipal governments and the average family were rich enough, we’d all just line our streets and driveways with heaters. Reality is, we can’t.
So what are the alternatives to road salt? Sand, for starters. Many Canadian prairie cities HAVE to use sand, because road salt is only effective for temperatures between 0 and -18 degrees. Sand knows no such limits. But, sand doesn’t dissolve as conveniently as salt. So its cleanup costs make it non-ideal.
Road Salt is sodium chloride, and chlorides conveniently disappear, more or less, on their own. So a less corrosive chloride, that can melt ice (or allow for traction on ice) is the answer. They exist, and include magnesium chloride, calcium chloride, and potassium chloride.
But they’re costly. So costly that the voting public would have the head of a council expecting taxpayers to foot the bill for them. The road salt we use costs $25-40 per tonne, whereas magnesium chloride runs about $134-$242 per tonne, and calcium chloride is 4 times as much (source: Cornell University).
Urea is another option. Yes, the stuff in pee. But that’s crazy expensive at roughly $430 per tonne. So, road salt it is, despite the aforementioned potential for post-salting damage of our stuff and things and natural environment. Road Salt’s effect on wildlife and the environment is so bad that Environment Canada wanted to add it to a list of the country’s list of the most toxic substances.
But what’s a city to do, except safety first, within its budgetary realities? If there’s a Chemistry grad reading this, put your thinking cap on under your toque this week. There’s big money in the first solution to fix Canada’s road salt pickle.
RE: pickle, pickle juice has already been assessed and used in New Jersey. Its brine has natural chlorides that get into the porous parts of pavement and prevent snow and ice from collecting in there. Beet juice, sprayed before a storm, prevents ice from bonding with a road too, and can increase road salt’s effectiveness so it works in temps as low as -30 degrees.