“It sticks to cars like molasses”: Salt and Brine

Shaun Brown, a mechanic at Utton’s automotive, stands under a 2007 Toyota Yaris.  Looking up at rust forming in front of the rear wheels, he notices a golf ball sized hole where the rust has gone through.

This car came to Vermont just three years ago from New Jersey and wasn’t rusty at all. The owner didn’t wash it much or get it undercoated, but she is still disappointed that the car is not going to pass inspection.

This is just one of many newer cars in Vermont that are completely rusted out. Cars that are 20 or 30 years older than this one are in near perfect shape in other parts of the country. Why is it that Vermont is dumping more and more salt on the roads?

In the Western States where it snows, they don’t salt nearly as much as we do here. This is in part because there is more sun, so snow and ice melt a lot faster. However, the effects of less salt on the roads result in cars lasting a lot longer.

While we live in a snowy and rainy environment, that doesn’t account for how quickly a car rusts here. The reason they rust so badly is indisputably salt, but is it getting worse?

Chip Harrington, another mechanic in Montpelier, explained that he didn’t think it was just the salt. “It seems like cars are rusting out faster now than they did 13 years ago when I started,” Chip said. “It might be that they are making cars out of cheaper metal now. That combined with the new deicing chemicals they are using on the roads seems to be making cars rust out more quickly.”

The deicing chemicals he is talking about are brine and calcium chloride. Brine, a rock salt with magnesium chloride, is melted in water and sprayed on paved roads in the winter. In theory, this is a better way of melting ice on roads at lower temperatures than salt. As Shaun put it, “it sticks to cars like molasses. I don’t like regular road salt, but I’ll take that over brine.”

Another fairly new corrosive agent being used is calcium chloride. Calcium chloride is sprayed on dirt roads in the summer by some towns to keep dust down, which it does, but again it’s a trade-off. Is it really worth having another six months a year of salt just for a little less dust?

What is the real cost of all this you might ask? Why does it matter? Besides the direct effects of salt on cars, in the form of corrosion, salt has a similar effect on the asphalt that roads are made of. The salt leads to roads deteriorating sooner, leading to more and worse potholes.

When winter is over, the salt doesn’t just go away. The majority of it stays within the local watershed. Salt kills roadside plants and gets caught up in the runoff, leading to more saline lakes and streams.

Salts main benefit is that it makes roads safer, and makes them passable in almost all weather conditions. It decreases weather-related accidents, but we can’t simply overlook all the damage it causes.

“In most other places you can buy a car new and expect to have it as long as you want, provided you maintain it properly”, Chip said. “Here you get ten years out of a brand new car. Maybe 15 if you undercoat it. Some cars even less.”

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.