A Sustainable Snow-Free Pavement to Mitigate the Negative Effect of Road Salts on Soil and Water Environment

Project Details









Robin Kline, Omid Ghasemi-Fare


Office of the Assistant Secretary for Research and Technology


Alternatives analysis, Deicing, Deicing chemicals, Environmental impacts, Geothermal resources, Heat exchangers, Runoff



Project description

Extreme weather in winter, characterized by prolonged and severe conditions, is anticipated soon due to climate change. Consequently, the utilization of deicing chemicals such as salts (including Chloride-based, Formate-based, and Acetate solutions) is inevitable. These chemicals are employed to ensure driving safety and minimize fatal accidents, particularly on critical infrastructure like bridges, highway ramps, and transportation corridors. However, the introduction of chemical solutions into surface runoff, with subsequent infiltration into groundwater, poses significant environmental challenges. This phenomenon can have adverse effects on both soil and water ecosystems, potentially accelerating water eutrophication. Long-term road salt application leads to elevated chloride concentration in groundwater, rivers, lakes, and freshwater bodies, which disrupts aquatic ecosystems. Additionally, sodium chloride (NaCl) impacts abiotic processes in soil and water. A recent study conducted in New York highlighted the impacts of road salts on private wells in the Town of Orleans, New York State. Moreover, road salts can alter soil structures and influence biotic communities. Therefore, it is imperative to explore alternative pavement de-icing methods to mitigate soil and water contamination. This project aims to reduce chloride pollution in soil and water ecosystem with the use of active (circulating heat carrier fluid) or passive (use of higher thermal conductive elements) geothermal system. Shallow geothermal energy presents a viable solution for pavement de-icing, promoting safety while eliminating the environmental concerns associated with chemical deicers. In the case of active geothermal systems, heat exchanger tubes can be embedded within the concrete pavement to effectively de-ice the surface. Additionally, the project will investigate an innovative passive system that leverages geothermal energy to prevent ice accumulation on the pavement surface. The passive approach involves the installation of solid heat exchangers composed of materials with high thermal conductivity, deep within the soil (20 to 30 feet) to transfer geothermal heat to the surface. Both active and passive geothermal systems offer alternatives to chemical usage, particularly road salts, thus preventing soil and water contamination. By embracing these geothermal solutions, the project aims to revolutionize pavement de-icing practices while safeguarding the environment.