Use of Liquid Anti-Icing to Reduce Chloride Inputs to the Environment from the Winter Maintenance of Parking Lots

Because of the application of road salt (e.g., sodium chloride), chloride concentrations in the environment are increasing in cold climates around the world to levels that often exceed guidelines for the protection of aquatic life. With no cost-effective means of removing chloride once it has entered the environment, best management practices (BMPs) for reducing its application in the first place are required. Liquid anti-icing is a BMP that has been shown to reduce chloride application to roads, but its efficacy for parking lots has not previously been demonstrated. This research demonstrates that liquid anti-icing can reduce chloride application to parking lots, and thus, input to the environment, on average by 31%. Additionally, this research finds that using a liquid anti-icer supplemented with an organic (in this case, beet juice) additive can further reduce chloride application, on average by 32% over a simple sodium chloride product. These findings should encourage watershed managers and landowners to promote the widespread adoption of liquid anti-icing by winter maintenance contractors. Watershed managers will need to weigh the trade-offs between the potential environmental impacts of organic products like beet juice and of the chloride it may offset, before recommending the widespread use of organic ice melting products.