The project produced guidelines for selecting roadway snow and ice control strategies and tactics for a wide range of winter maintenance operating conditions. These guidelines apply to highways, roads, streets, and other paved surfaces that carry motor vehicles--under state or local jurisdictions and provide a basis for selecting the appropriate level-of-service (LOS)-driven roadway snow and ice control operations.
Snow and ice control on the U.S. highway system consumes billion of dollars--in direct costs and costs associated with corrosion and environmental impacts--each year. Strategies and tactics that employ solid and liquid chemicals, abrasives, and mechanical methods--individually or in combination--have been used by state and local agencies. In spite of many studies of issues associated with snow and ice control treatments, widely accepted guidelines for selecting roadway snow and ice control strategies and tactics for specific climatic, site, and traffic conditions have not emerged. Therefore, there is a need to develop guidelines that delineate a process of selecting treatment strategies and tactics that meet highway agency objectives.
The research (a) identified the climatic, site, and traffic conditions that affect the selection of snow and ice control strategies and tactics to achieve agency objectives (e.g., LOS), and listed in a rank-order the criteria necessary to assess the performance of treatments; (b) identified the snow and ice control strategies and tactics in current use that may be applicable to U.S. conditions and highlighted for each strategy and tactic the conditions of use, selection criteria, evaluation methods, effectiveness, and related problems; (c) identified specific snow and ice control strategies and tactics that merited further evaluation and developed a plan for their field evaluation in different environments under different site and traffic conditions; (d) conducted investigations of several potential snow and ice strategy and tactic combinations during three winter seasons and collected information necessary to relate the effectiveness of each of these combinations to the climatic, site, and traffic conditions; and (e) developed guidelines that can be used for selecting appropriate snow and ice control strategies and tactics for specific climatic, site, and traffic conditions to achieve agency objectives. The findings of this research pointed out the importance of (1) ensuring that snow and ice control strategy/tactic combinations are LOS driven; (2) using nowcasting results, materials characteristics, traffic volume, and cycle time considerations in the treatment decision making; and (3) providing flexible winter maintenance operations to deal with the variety of precipitation types, especially those occurring within a given weather event.
NCHRP Report 526: Snow and Ice Control: Guidelines for Materials and Methods contains the guidelines developed in the project.