Rock salt–the stuff that’s poured all over roads to keep them from icing over in the winter–is a disaster on multiple fronts. Here’s why.
What Is Road Salt?
Road salt is basically just an unrefined version of the stuff you put on your food. This form of sodium chloride (NaCl) is typically mined from the underground remains of long-dead oceans all over the world. Pretty cool, huh?
It works by lowering the temperature at which water can freeze, making it harder for ice to form on plowed roads.
We dump millions of tons of this chemical on our roads and sidewalks every winter, and for good reason. A study in 1992 found that road salt reduces car accidents by as much as 87% in bad weather.
The economy would lose billions every year if society ground to a halt in wintertime, but there are other costs that you might not have considered before.
Harmful Effects of Rock Salt
It’s estimated that salting our roads costs over $7 billion a year. The biggest part of that bill is fixing the damage caused by the salt.
Salt is corrosive. It has a huge impact on steel–you know, the stuff that forms the frames of our cars, as well as our bridges, and even the rods in concrete. Over time, that corrosion weakens the metal.
There’s also a big problem brewing as the sodium and chloride get washed away with the melting snow and ice. Chloride levels in rivers and streams has risen by more than 80% in the 90 years we’ve been using road salt.
That’s bad for the plants and animals that live in that water, and it’s bad for our drinking water, too.
How to Prevent and Repair Salt Damage
As you drive along salted, slushy roads, the undercarriage of your car is being constantly splashed with corrosive sodium chloride. Even worse, the salt can build up in hard-to-reach places, such as wheel wells. Pretty soon, your ride will be a rust bucket–unless you take action.
The first step in any auto maintenance plan should be prevention. If you live above the “snow belt” where roads are commonly de-iced with salt, then take your car to a body shop that can provide a pre-winter oil treatment to the undercarriage. This will help salt from sticking in the first place. It’s also a good idea to wax your car in the fall.
Next, get in the habit of taking your car through a brushless car wash with an under-car spray. You don’t want to powerwash the vehicle by hand, as that can actually blast the salt deeper into those tricky areas that are already hard to clean.