Vermont conducted a case study back in 2009 on the effectiveness, cost, and effects of road salt and sand to combat winter road maintenance. Vermont spends over 15 million dollars annually on winter road maintenance. Plus, 4 million dollars on 75,000 tons of salt and 21,000 tons of sand. As temperatures fluctuate through winter, Vermont Agency of Transportation uses different amount of salt to melt ice. At 30 degrees a pound of salt will melt 46 pounds of ice. At 20 degrees 5 pounds of salt will melt 46 pounds of ice. At 10 degrees about 9 pounds of salt will melt 46 pounds of ice. When the temperatures get below 10 degrees sand is used because the cost effectiveness and efficiency of salt is not proportional.
As of 2009 road salt and sand is the most foreseeable option for melting ice. However, sand can absorb pollutants and can be carried into drainage paths and clog systems, effect the turbidity in water bodies or cause silting problems in water bodies. Salt can pollute the environment by clogging wells, contaminating ground water, increasing chloride levels in bodies of water, salt-induced vegetation die off and cause corrosion to structures, vehicles, and roads. "Vermont also pays enormous undocumented costs due to increased accidents in the winter, damage to natural environment from salt and sand, and maintenance costs due to corresponding corrosion of our roads, bridges, and vehicles" (2008-09 Winter Maintenance Season Final Report). Stay tuned for next blog post to see if Vermont has changed its methods since 2009.