by Avery Prudenti ‘22
Anyone in Olney who looked outside their window over the past few weeks often saw snow on the ground. Along with that winter precipitation comes the salt covering the roads. This regular practice works as an effective way to clear the roads of snow quickly, and sometimes without the need of a snow plower at all. The road salt works by lowering the freezing point of water, which in turn melts the snow and makes it more difficult for the water to then freeze into ice. This process has been used in the United States since 1938 and now between 10 to 20 million tons of salt is used per year on roads.
While the process is effective, salting roads is destructive to the environment. When the salt is used on roads and highways, it then drains into the ground along with the melted water. These large amounts of salt are lost in the ground and slowly seep into many freshwater systems. Aquatic ecologist Andrew Juhl notes that, “Once salt gets into the soil, or into a waterway, there really are no biological processes that will remove it.” These millions upon millions of tons of salt are seemingly vanishing, but in reality, they are just dissolving into essential freshwater systems and polluting them. Too much salt in freshwater can cause oxygen depletion in larger bodies of water, which is disastrous to the aquatic animals living in these ecosystems.
While these effects of salt are very damaging, the practice for de-icing roads remains so common because of the difficulty of finding a solution that is cheaper and more effective than salt; but there are options. Kirsti Marohn from MPR News states that, “The Minnesota Department of Transportation has been experimenting with potassium acetate as an alternative to road salt.” The department believes that this could be a possible solution because it is better than salt at melting ice in extremely cold temperatures. Salt is not very effective in colder temperatures, especially below about 15 degrees, but potassium acetate is. It is about three times more expensive than salt is, but less of it is needed. However, the environmental impacts of potassium acetate are still unclear,” says Mrohn, “the chemical eventually breaks down in the environment … but lab tests have shown it’s toxic to aquatic insects.”
Another promising solution could be cheese brine, as crazy as it might sound. The brine used in cheese is very salty and it actually soaks into the roads instead of running off them. It also has a lower freezing point compared to salt, which actually makes it more effective in lower temperatures than salt. This solution could possibly be used alongside other eco friendly solutions to combat the massive amounts of salt used every year.
It is going to be hard to find a solution that is completely effective and harm-free, but there are options that are better than others. Salt is still the normal, go-to option for melting ice on the road, but that may change in the near future. The damage to fresh water systems that the salt causes is a very serious problem and many believe that switching to potassium acetate, cheese brine, or other solutions, may be the better option.