History of Salt Use

Salt use began on roadways in the late 1930s in New Hampshire. The application of road salt proved to help maintain safer winter roads, parking lots, sidewalks, and other paved surfaces. As the amount of paved surface increased, salt use increased. The demand for clearer roads and bare pavement also increased with public expectations for winter travel.

Unfortunately, salt use also has negative impacts, which are very costly, including:

• Contamination of surface water and groundwater
• Toxicity to plants and animals
• Damage to infrastructure and vehicles
• Degradation of soil structure
• Disruption of seasonal lake mixing
• Contribution to “freshwater salinization syndrome,” which accelerates the release of metals and other pollutants into water

Many salts contain chloride which is a permanent pollutant. Chloride does not break down over time. The best way to reduce chloride pollution is to prevent it from entering the environment — because once it contaminates water, it cannot feasibly be removed.

In this section, we will learn what salt is and how it works. We will explore the benefits and negative impacts of salt use and share practical steps homeowners can take to keep driveways and sidewalks safe during winter — while using less salt to reduce hidden costs and prevent damage to pavement, lawns, and the environment.