Where All that Road Salt Ends Up
April 3, 2014
There is a lot of salt on the roads this time of year. Salt reduces the freezing point of water, so it is useful for keeping our roads, parking lots, and sidewalks free of ice. Salt is also cheap, so we tend to use a lot of it. As New Englanders, we know that salt eats away at our cars, but we accept this as a trade-off for safe roads and sidewalks. Unfortunately, the adverse effects of salt are not limited to the rust on our cars. Salt is also really bad for lakes, rivers, and drinking water.
Think about where all of the road salt goes. It gets washed from parking lots into storm drains that dump into lakes and rivers. It is washed to the side of the road where it seeps into the ground and contaminates groundwater and drinking water wells, or it gets washed directly into a stream, pond, or lake. Think about how many of our roads are right next to water.
When traditional road salt dissolves, it divides into sodium and chloride. People with high blood pressure need to be concerned about too much sodium in their drinking water, and sodium in your drinking water can come directly from road salt. As for chloride, it is toxic to aquatic life above certain levels. There are at least 40 water bodies in New Hampshire that are polluted by too much chloride and therefore categorized by the government as “impaired.”
Many of us get our drinking water from private wells, and many of our wells are located close to roads. If your well becomes contaminated from with road salt, it can be very difficult and expensive to remove. Your well may already be contaminated, but you may not know it because there are no requirements in New Hampshire that private wells be tested.
In addition to its effects on humans and aquatic life, the adverse impacts of salt include making the pads on dogs’ paws crack, deteriorating our concrete infrastructure, and ruining a good many pair of shoes. Often, harmful and toxic chemicals are added to road salt, including ferrocyanide. I don’t know much about ferrocyanide’s environmental or health effects, but the fact that half of its name is the word “cyanide” is enough for me to prefer that less of it be in the lakes where I fish.
I am not suggesting that we stop using salt, but I am suggesting that all snow plow operators in New Hampshire become certified in a new certification program called Green SnowPro Training. The Green SnowPro program was developed by the University of New Hampshire Technology Transfer Center and is administered in conjunction with the New Hampshire Department of Environmental Services.
Last year, a law was passed establishing the certification process. For $60 dollars (which includes lunch!), plow operators can take a half-day course in which they will learn techniques of applying road salt and other de-icing chemicals more efficiently and effectively. The training discusses making salt brine as well as the effectiveness of salt and other de-icing chemicals at various temperatures. Rock salt, for instance, is ineffective at temperatures below 15 degrees Fahrenheit.
The new law provides a significant incentive for snow plow operators to become certified and follow best management practices. The law provides certified plow operators—and the property owners who hire them—with legal immunity from many “slip and fall” claims.
If you operate a snow plow, please get certified, and then use your certification as a marketing tool for your business. If you are a business owner who hires someone to plow and salt your parking lot, ask your plower to get certified, or hire a plower who is certified. If you are a town official, encourage your town to send its operators to the Green SnowPro course. Some towns have already done so. The minor expense of the training will quickly pay off in salt saved and water-quality problems averted.