Road salt has been used to combat icy roads for decades. Over the years, application techniques and storage methods have changed. But, are there other ways to keep drivers safe in the winter?
When Mother Nature serves up cold, snow and ice, municipalities and DOTs across the United States turn to sodium chloride to deice their roadways. This compound is very similar to common table salt, albeit a much coarser version. It’s an affordable, effective means to remove snow and ice from our roads—keeping people safe. However, the compound is only effective in temps above 15 or 20 degrees. So, what else can we use? Turns out, there are a lot of alternatives.
There are quite a few different methods to prevent snow and ice build-up on our roads, some more common than others. Here are some of those methods.
Calcium chloride can melt snow quicker and at a lower temperature than salt, but can damage roadways, vehicles and more. What’s more, is calcium chloride melts snow and ice so quickly it leaves behind lots of moisture. This leftover moisture can then refreeze if it’s cold enough.
Potassium acetate can be applied before a snow or ice event to prevent sticking to the pavement. Fewer applications are required as it continues to work longer than other pretreatment methods. The problem is it can lower oxygen levels in waterways and do damage over time.
Calcium chloride and potassium acetate are also more expensive than sodium chloride (road salt).
Although some of these alternatives are effective in deicing roads, they’re just not as economical and plentiful as salt. And, there is limited infrastructure in place to support these alternative methods.
“If we think about road salt and how long we’ve been using it,” says Brad Woznak, SEH water resources engineer, “there is a whole infrastructure built to support it.”
How would a new deicing agent get to communities? How would it be stored? Where would it be stored? Answering these questions would surely come with their own costs. It’s partly because of these economic factors that Woznak says more communities don’t explore alternatives to road salt.
By smartly reducing the amount of salt on roadways, and combining it with some of the brines mentioned earlier, we can continue to have successful results reducing snow and ice. Municipalities and DOTs are using electronic spreading systems on their trucks to intelligently deliver just the right amount of salt to roads and parking lots. They are timing their salt applications better and using less salt overall.
Road salt has been the mainstay in fighting the battle of roadway snow and ice for decades, but new technologies have shown promise. As we progress into the future, it’s important to know what technologies exist that can help us along the way, and how to evaluate our current methods.
Brad Woznak, PE, is a water resources engineer dedicated to environmentally-sound, smart solutions. Contact Brad