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Salt on the Roads

Susan J

When winter weather is approaching, you will begin to see utility trucks pretreating the roads with brine, preparing them for snow and more salt. They are coating the roads so that we can access them sooner, hopefully with less traffic accidents. Rock salt or liquid salt is used after snow falls and ice storms, and can usually be seen to the eye. Often, you can see white residue while driving, and hear small rocks hitting your vehicle. In more recent years, many cities use liquid salt as well as rock salt. What exactly is this mixture which is on the roads? Is it safe for you, the environment, or your vehicles?

The salt that is used on roadways is typically a course mix of sodium chloride and non-caking agents such as sodium Ferro cyanide and ferric Ferro cyanide. One of the biggest advantages to road salt is that it is readily available and inexpensive. However, it does have limitations and risks.

Salted Pavement

First, it does not work under extremely cold conditions. Instead, sand is used for temperatures under 15 degrees. Sand provides traction to help with slippery roads and provides friction to aid ice and snow melting.

Secondly, sodium chloride, potassium chloride, magnesium chloride and calcium chloride, which are types of Rock Salt, all pose significant risks for the environment. Because rock salt is not purified, it contains contaminants such as lead, iron, aluminum and phosphorus that are released into the ecosystem and can raise the salinity in the soil and water. In addition there are added melting and non-caking chemicals which can add to these dangers.

Thirdly, there is the corrosive properties of Road Salt. This extensively affects our vehicles and structures.  Although great for protecting drivers from slick snow and ice, salt is harsh on your vehicle’s surfaces and running parts. Corrosion and friction are not your automobile’s friend. Corrosion is the result of an electrochemical reaction combining iron and oxygen to form iron oxide. In the driest of climates, oxygen in the air will eventually cause iron to corrode. But when water enters the picture it steps up this process, especially if it is “ion laden water.” This brings us to Sodium Chloride, the most common and inexpensive type of road salt. When this “road salt” melts snow and ice it dissolves into its parts, sodium ion and chloride ion. These free floating ions, combined with the oxygen in the melted snow water and the iron of the car, facilitate the perfect environment for rust. This leads to a domino effect. More rust produces more chemicals which in turn creates more rust. Unfortunately this cycle does not stop unless all of the corrosion is removed and the base metal is protected by some form of barrier. Daniel Strohl of Hemmings Daily has an interesting analogy in his article titled, “How exactly does road salt cause cars to rust?” It reads, So, in a way, we can look at driving on salted roads as akin to repeatedly bashing your head against a brick wall. Sure, we’re all ‘gonna’ die anyway, but some behaviors will certainly accelerate that process.”

On that note: since road salt is a severe accelerate to rust, many alternatives have been discussed as listed in “The Chemical Composition of Road Salt” by Anne Marie Helmenstine. But due to its economic benefits, road salt is still used extensively. Here are a few things to do to limit the damage of corrosion and exposure in your vehicle.

  1. It is important that that you wash your vehicle thoroughly as soon as possible after driving through salt and snow. The salt and prolonged moisture will generate damage to your paint job, frame, undercarriage and electrical parts. Once the temperatures are above 40 degrees, wash your vehicle to remove the salt. If possible allow to dry thoroughly in the sun.
  2. Search for “Anti-Rust primer for automobile” in your favorite internet browser. There are some interesting and viable offerings.
  3. People who live in climates with a lot of snow and ice suggest buying a low priced vehicle specifically for driving during the winter. Come spring they uncover and enjoy their “valuable vehicles.”
  4. Move to a town in Wisconsin that uses cheese brine as a de-icer.

Northern states may be subject to these conditions more often than others, but winter weather falls into the category of the unavoidable. Despite your location, you will most likely be exposed to salted roads at some point during the winter season. Remember to wash your vehicle’s exterior and undercarriage in a timely manner, it will benefit your vehicle in the long run. And to keep your vehicle in tip top shape use a breathable car cover on your vehicle, such as the ones found at Car Covers Direct.

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