My local landscape has been covered with road salt the last couple of weeks, due to periodic snowfalls and temperatures consistently below freezing. I can’t say I am sorry to have steps and sidewalks clear of ice (with my bad back, a fall could be disabling), but I wish the landlords and homeowners that dispense it knew more about what they were doing.
Most people use far more salt than is necessary and apply it too late. They also think that salt is a substitute for shoveling, which it’s not.
It wouldn’t be a big deal if salting were safe, but it isn’t. When salt blows over soil, seeps into groundwater and washes into lakes and streams, it destroys habitat for plants and animals. (The ill effects on roadside plantings, grass and trees are a common sight come spring.) And that’s not all. Infrastructure is harmed by excessive salt use, as are cars and footwear. Pets whose paws have been exposed to salt may end up ingesting a toxic amount when they try to lick their paws clean. The effect on human health of drinking water with excess salt has yet to be studied.
But not de-icing isn’t safe either.
Unfortunately, there is currently no competitively priced de-icing alternative to salt. Calcium magnesium acetate (CMA) appears to be the best option, based on current research, but it is many times more expensive than salt. Still, it’s not expensive in itself, just comparatively, and won’t break the bank if you only have a small amount of pavement to de-ice. A less expensive solution is to use a de-icing blend containing salt mixed with CMA or another, less studied but promising alternative called potassium acetate (KA).
All work best when applied early on to pavement that’s been cleared of snow.
For more on the subject, see my latest This Green Life column for NRDC, The Safe Road in Winter.