Transport and Fate Processes of Road Salt in Urban Areas

这项研究计划的总体目标是更好地保护城市流域可持续和安全的饮用水源和淡水水生生态系统，使其免受加拿大每年用于冬季道路养护的500万吨道路盐的新威胁。本研究将推进冰雪融化过程（热融化、雨对雪融化和盐引起的融化）和各种类型冬季风暴（干雪、湿雪、冻雨或雨对雪）的氯化物冲刷率的科学知识，以更准确地计算地表径流中的氯化物浓度以及城市流域地下水补给。这项研究将有助于开发新颖、实用和可行的方法，以尽量减少城市流域道路盐施用对环境的潜在负面影响。具体而言，本研究将重点改进“盐易损区”识别和关键来源对敏感受体贡献计算的科学方法，并为更有效地利用现有的实时天气预报和道路天气信息系统来优化道路盐的施用量提供知识；优化预湿和直接液体除冰应用，以最少的盐量实现更均匀的路面牵引力；利用无线盐车实时监控和操作系统，更好地保护盐易损区；开发地下蓄水池的创新设计，以捕获和控制排放受污染的径流，以保护易受盐影响的地区。这些发现的主要成果将是促进加拿大的盐管理实践和改善环境保护。该研究项目将支持两名博士生、两名硕士生、一名博士后和五名本科生，在项目的五年时间内，他们将为市政当局、道路当局和私人承包商开发新技术，包括新的软件和专利，预计将为加拿大带来就业和收入。

The overarching goal of this research program is to better protect sustainable and safe drinking water sources and freshwater aquatic ecosystems in urban watersheds from the emerging threat of the 5 million tonnes of road salt that is applied annually in Canada for winter road maintenance. This research will advance scientific knowledge on the ice and snow melt processes (the thermal melt, rain-on-snow melt, and the salt-induced melt) and the chloride wash-off rate for various types of winter storms (dry snow, wet snow, freezing rain, or rain on snow) to more accurately calculate the chloride concentrations in both surface runoff as well as the groundwater recharge in urban watersheds. This research will assist in the development of novel, practical and feasible methods to minimize potential negative environmental effects of road salt application in urban watersheds. Specifically, this research will focus on improvement of the scientific methods of identification of the "salt vulnerable areas" and calculation of the contribution of the key sources to the sensitive receptors andwill advance knowledge for more effective use of the available real-time weather forecasts and the road weather information systems to optimize the road salt application rates; to optimize pre-wetting and direct liquid de-icer application to achieve a more uniform road surface traction with the least amount of salt; to take advantage of the wireless real-time salt truck monitoring and operation systems to better protect salt vulnerable areas; and to develop innovative design of underground detention tanks for capture and controlled release of contaminated runoff to protect the salt vulnerable areas. The main outcome from these findings will be advancement of salt management practice and improved environmental protection in Canada. This research program will support two doctoral students, two masters students, one postdoctoral fellow and five undergraduate students, over the five year duration of the project, who will develop new technology for the municipalities, road authorities and for the private contractors, including new software and patents that is expected to result in jobs and income for Canada.