The purpose of this research is to review Arizona Department of Transportation's (ADOT's) existing snow and ice control practices and procedures and to make recommendations to improve snow and ice control. The research uses the level of service (LOS) goals from a maintenance management system (MMS) to make recommendations for improving procedures and acquiring resources in order to attain the LOS goals. The main recommendations in applying de-icing and anti-icing chemicals include: (1) Where LOS goals and siteconditions allow, ADOT should implement anti-icing as a standard strategy. (2) The reasonable amounts of chemicals in anti-icing operations shouldbe based on current and expected conditions. (3) The concentration of chemicals applied can change over time, i.e., become diluted, with the interaction of the chemicals, precipitation and accumulated snow or ice. Care should be taken in applications of chemicals when the diluted potential ismedium or high. (4) The recommended treatment strategy for localized icing conditions is pre-treating with a liquid ice control chemical 6 to 66 hours before the potential event. Liquid ice control chemicals are also effective in treating black ice that has already occurred if the pavement temperature is above 23 deg F (-5 deg C). The research has found that the current ADOT snow and ice fleet size, character, and associated support resource are not adequate to provide the LOS desired. It is recommended that30-50 additional snow and ice trucks should be acquired. ADOT also should conduct a route-by-route analysis to realign existing resources to be compatible with highway priority and cycle time. In order for ADOT to successfully attain its LOS goals, it needs to adopt a chemical priority policyfor the use of chemicals in snow and ice control where possible. This policy would apply to both anti-icing and deicing strategies. This will require additional cost for chemicals and reduced cost for cinders. It is also recommended that ADOT should establish a formally programmed, user driven, and continuous technical training program for snow and ice control. The training goals and objectives should be established. By establishing such a program, consistent practices and procedures can be implemented effectively and efficiently.
Abstract