Senior Investigates the Environmental Effects of Road Salt in Crawford County

Mary Allen
Mary Allen

Together, Pennsylvania and New York use 1,215,660 tons of road salt each winter to melt snow and ice. Allegheny College student Mary Allen ’22 used her Senior Comprehensive Project to examine the negative impact of road salt on the environment — and to explore more eco-friendly alternatives to help keep travelers safe. 

“I am extremely grateful for the opportunity to be able to do this research and carry out my own project while I am in my undergraduate studies, as it is something that really has made me stand out in applying to jobs,” says Allen, who is majoring in environmental science & sustainability with a minor in energy & society. “It has taught me a lot about myself, what I like to do, as well as the capabilities that we have as students with the guidance of such great professors at Allegheny.”

At the start of the project, Allen visited two creeks that intersect French Creek for her research —  Gravel Run and Cussewago Creek. Samples were collected from each creek before snowfall, during winter, and when snow began to melt. After collecting the samples, Allen measured their sodium levels. She found that the sodium content of the water was higher from the onset of winter. 

Unfortunately, higher sodium levels harm freshwater ecosystems and the organisms in them. It also can pollute drinking water, which can create health risks.  

“Environmental Science and Sustainability faculty Kelly Pearce, Rich Bowden, and Sam Reese have been extremely encouraging in my efforts to complete this project,” says Allen. “I would not have been able to utilize the resources that I was able to use nor would I have the determination to carry out this project and be pushed out of my comfort zone.”

To take her research further, Allen is investigating alternatives to salt that consider the environment, economy, and road safety. Sand and beet juice are among some of the alternatives she has studied. Using sand has been proven to give tires more traction, although it isn’t practical for de-icing. Beet juice, on the other hand, has been observed to melt ice in temperatures above zero degrees Fahrenheit. 

“The major takeaway from doing this project would be that when your project involves fieldwork, everything is not going to work out exactly as planned,” says Allen. “You learn to adjust your research and that the results aren’t always going to turn out exactly as expected, especially when working outside in the wintertime.”

After graduation, Allen intends to secure a job in environmental science and pursue graduate school to prepare for a career in the natural sciences.