Water quality issues with road salt

  • Published
  • By Courtesy article
  • 88th Civil Engineer Group

With winter fast approaching, it will be time again to see CE salt trucks and snow removal crews doing the excellent job that they always do with keeping roads clear and the mission moving forward. There are only a few products that are effective at removing snow and ice from our numerous roadways, with road salt and liquid brine solution being instrumental tools.

Road salt and liquid brine are commonly used substances to prevent or eliminate ice that has formed on various surfaces. This practice originated in the 1940s and 1950s when only about 5,000 tons were spread annually on roads and surfaces across the country. However, in the following decades, road salt usage has grown exponentially, and we now use about 20 million tons of road salt annually—roughly 123 pounds for every American. This exponential increase in road salt has caused various problems for water quality and water-related infrastructure over these past 70 years of usage. The problems are even more significant in highly urbanized areas where chloride levels are much higher because of the large amounts of impermeable land cover.

These deicing chemicals work by lowering the freezing point of the ice that is present on the surface. It forms a brine, which causes salt crystals, usually sodium chloride, to pull water molecules out of the ice. This brine then dramatically speeds up the melting process as it continues to form over time. The sodium chloride in the applied salt is then dissolved into sodium and chloride ions and makes its way into the environment, where they can cause many problems.

Even though there are environmental issues with these products, we do need to utilize them to ensure that the health and safety concerns with snow and ice are mitigated. We just need to ensure that they are being used in appropriate areas and appropriate quantities. This also applies to each organization that uses salt for sidewalks and door areas. Shoveling as much snow as possible is an easy first step to ensure minimal salt usage. Also, applying the minimal amount necessary to melt the remaining snow and ice is an easy step to ensure minimal runoff issues into our waterways.

Protecting our natural resources that are on the installation takes everyone doing the little proactive actions. Water that is on our installation quickly moves to our neighbors and surrounding communities. We can easily keep areas safe without unnecessary environmental impacts if we think about the impacts of overusing salt for snow and ice removal. It only takes small efforts to make a large overall impact.

If you have any additional questions on any water quality issues, please reach out to Michael Vaughn, CEG/CEIEA, at michael.vaughn.3@us.af.mil.