Effective Pre-Treatment Method for Events Beginning as Rain

Project summary:

Chloride-based salts have been used for decades in the cold climate regions of the United States as an effective snow and ice management technique for winter roads, parking lots, and sidewalks. Chloride-based salts, however, have negative environmental consequences such as corrosion to steel, increasing chloride concentration in nearby water bodies, and the breakdown of soil structure. The use of anti-icers (applying chemicals before precipitation) is one method to reduce chloride- based salt application, because the amount of salt required for safe surfaces is substantially reduced. A recent Clear Roads Synthesis Report (?Use of Prewetted Solid Materials for Roadway Anti-Icing?) found that a majority of state Departments of Transportation (DOTs) believe that ?storms that begin as moderate to heavy rain? would preclude the use of anti-icing technology. This research project will review peer-reviewed literature, survey state DOTs, develop a testing protocol, and conduct experiments to determine how much the effectiveness of anti-icing applications is reduced when winter precipitation events start as rain. With an understanding of how rainfall affects anti-icing techniques, a quick reference guide will be developed for winter maintenance personnel, the final report will be written, and a webinar will be presented to share the results of this project with transportation professionals throughout regions of the United States that experience winter climate. With the information discovered during this research project, winter road maintenance professionals will know how much anti-icing chemicals to apply during precipitation events that start as rain, which will increase safety and reduce the negative environmental impacts of chloride-based salts.