A COMPARISON OF SURFACE WATER SALT CONCENTRATIONS FROM DIFFERENT ROAD SALTING METHODS

Road salt applications have been prevalent since the 1960s, resulting in notable increases in concentrations of chloride in surface and ground waters since that time. Today, rock salt (NaCl), as well as other types of salts (ex. MgCl, KCl, K-acetate) and salt alternatives (ex. beet juice, cheese brine) continue to be heavily used on roads and sidewalks in snowy months due to their chemical composition which can substantially lower the melting point of water thus breaking the bondage of ice from pavement. Because of the widespread use, and often high application concentrations, these salts have become a source of significant environmental concern. As such, there is growing interest in adjusting salt types and concentrations as well as application methods. Therefore, this research sought to compare saline surface water concentrations from two areas using different salting applications; the city of Albion, MI and the adjacent campus of Albion College. Samples were collected from puddles created by meltwater on sidewalks, in roads, and parking lots, as well as two sample locations (upstream and downstream) in the Kalamazoo River, which runs through both the city of Albion and the college. Samples were analyzed for conductivity, pH, and in some cases major anions. By sampling these sites consistently throughout the winter season and monitoring the additions of road salts we gained an understanding of when and where higher concentrations of salts were present in the city and on campus. ArcGIS and ArcGIS Collector were also used in the salt concentration analysis by calculating and presenting correlations between the different methods and salts used by Albion College and the city of Albion and how these differences related to varying degrees of salt concentrations found between the two areas. In general, it was found that higher salinity concentrations were found in all areas during warmer days since the evaporation of melt water occurred, thus increasing the ratio of salt to H₂O. Because of the substantial ecological consequences of having high salt concentrations in the environment, the results of this study are an important first step in identifying differences in salt application methods. These observations can be used to help develop best practices in salt application methods that will aid in minimizing harm to the environment.