Our Salt Addiction
Each year, states in the “salt belt” spend millions of dollars on diesel fuel, driver overtime and truck maintenance, dumping 15 million tons of salt on our roadways. Winter road maintenance accounts for 20% of state level road maintenance budgets nationally, according to the Federal Highway Administration. State and local agencies spend more than $2.3 billion on salting programs annually. This salt performs a duty of temporarily reducing the freezing point of the water on the road surface until it is diluted by its own action. After doing its temporary job, the immense amounts of salt now become the source of infrastructure and environmental damage on a scale so large it becomes hard to measure.
The salt runoff is extremely corrosive, and it is estimated to cost the US $16-19 billion per year in infrastructure damage to culverts, bridges, overpasses and roadbeds. The environmental cost is even more startling. The salt does not simply dissolve, it builds up over time causing damage to plants, trees, wildlife and, most concerning, our own drinking water supplies. Thirty percent of all urban streams and 2% of all drinking water supplies in “salt belt” states now have sodium levels that exceed safe EPA levels. Damage to personal property is also a concern worth noting. Our cars and homes are both affected by the salt corrosion. It is common knowledge “salt belt” cars live much shorter lives than their western counterparts. Lastly and perhaps most interesting, is that the increase in deer we see along roads is not a coincidence. Sodium rich vegetation and runoff have brought mammals closer to our roads. The odds of a New York driver now hitting a deer have increased to 1 in 130 in 2018.
Does salting work? Yes, but the argument linking an increase in road salt use to a decrease in fatal winter driving accidents related to weather can be debated with the fact we simply have less snow and higher temperatures than we did in the past. Days when the temperature falls below 20°, the temperature at which traditional salt loses effectiveness, have also decreased significantly in the past 40 years. ABS and all-wheel drive systems have further reduced weather-related accidents. Salt and chloride solutions are not easily replaced but pretreating roads and using better judgment on when to apply them based on temperature and snowfall predictions can reduce their usage significantly.
Towns have taken different approaches in attempts to reduce salt usage. East Fishkill, NY, saved $243,000 in its first year after installing sensors on its trucks, helping the drivers make better application decisions. Other municipalities have successfully and significantly reduced consumption by simply loading trucks with less salt, forcing the drivers to use better judgement. Reduction, not banning, is the preferred approach by many.