Building a Model to Assess the Effects of Road Salt on Water Quality
Annually, approximately 20 million tons of road salt is applied in the United States. It is an effective and affordable deicer, but it comes with its risks. Specifically, chloride can be toxic to aquatic life. Because of the clear link between chloride and effects on amphibian health, the US Environmental Protection Agency has developed guidelines on recommended maximum chloride short-term and long-term exposure levels. The purpose of my work was to investigate whether aquatic life in the Fall Creek watershed in Central New York was at risk because of high chloride levels from road salt. Climatic, hydrologic, and field data were gathered to build a model that predicted chloride concentrations given a known amount of road salt applied. Based on model predictions of past, current, and future scenarios, chloride concentrations in streams did not exceed recommended limits. However, model predictions and field samples provided evidence that chloride concentrations in runoff greatly exceeded standards in the past and could continue to in the future. These results suggest that future modeling work be done that examines the relationship between spatial location and chloride level, with a focus on chloride in runoff.