Maintaining bare pavement conditions under winter storms is critical to the safe and expedient flow of road traffic in Canada. One of the principal snow and ice control methods is the application of salt. While salt remains to be the most cost-effective de-icer for road maintenance, its excessive use may have a detrimental effect on the environment and highway infrastructure. Improved maintenance techniques such as pre-wetting and direct liquid application (DLA) have therefore gained increasing popularity as a means of reducing the quantity of salt used. Past research has indicated that, while pre-wetted salt generally outperforms dry salt for snow removal, its effectiveness depends on the types and proportion of pre-wetting agents used and the road weather conditions under which it is applied. The primary objective of this research is therefore to investigate the effectiveness of different pre-wetting techniques under specific road weather conditions. The ultimate goal of this effort is to identify the optimal pre-wetting design (e.g. pre-wetting agent and ratio) for particular ranges of road weather conditions. Data collected by Ontario Ministry of Transportation (MTO) through a large scale field experiment called De-icing/Anti-icing Response Treatment (DART) was used in this analysis. This data consisted of measurements on snow cover, weather and pavement conditions, and treatment operations at 10-minute intervals over two winter seasons. The paper details an analysis of the snow melting trends on the test road under various road weather conditions and treatments, and summarizes the major findings related to the effects of pre-wetting chemical, prewetting ratio, and application rate.
