Although other chemical combinations and alternatives have been explored, rock salt remains the most common solution for clearing roads of snow and ice.
Using less salt can create safer roads Newer, smarter salt spreading technologies lower salt consumption while quickly creating safer driving conditions
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t first glance, it seems counterintuitive. Using more salt on winter roads should automatically create safer roads, right? Actually, scientific research tells us that’s not necessarily the case. And, in fact, often just the opposite is true. As confirmed by studies from a wide array of universities and municipalities across the country—from Maine to Ohio to Michigan to Wisconsin to Minnesota and more—what matters when it comes to winter road safety is not so much the quantity of the salt put down but, rather, the ratio of the salt mixture and the method by which it is spread.
Marcus Scherer, Ph.D. Senior Vice President of Research and Development Aebi Schmidt – North America Lindenwood, Illinois
Salt as an Effective Deicer Although other chemical combinations and alternatives have been explored, rock salt remains the most common solution for clearing roads of snow and ice. Why? Because it offers the greatest combination of benefits. It performs well, especially when compared with non-chemical options such as beet or pickle juice. According to the American Highway Users Alliance in Washington, D.C., road salt reduces
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crashes by up to 88% and injuries by up to 85%. It’s also cost effective, especially when compared with more sophisticated chemical alternatives like liquid calcium chloride, magnesium chloride or potassium acetate which are often as much as three times the cost of sodium chloride (a/k/a road salt).
Making Salt More Effective: PreWetting Strategies Pre-wetting is a strategy of applying a liquid deicing chemical to a dry solid before or during its application to the pavement. When a liquid is applied to a rock salt particle, the particle absorbs a minor amount of the liquid which increases its density. These heavier salt grains cushion the salt particles so they are less susceptible to movement. According to the Michigan DOT’s 2012 Bounce and Scatter study, about 30% of dry salt is wasted after being applied as a result of wind or traffic or bouncing off the side of the road. Pre-wetting reduces the amount of waste to 5% or less. This means you can spread 30%