Chemical and toxicological characterization of stormwater quality in the City of Saskatoon

来自降水事件和融雪的水作为雨水从城市景观中流出，并被收集到雨水下水道中。城市化进程的加快和土壤的密封导致了雨水的增加。与此同时，全球雨水质量下降，雨水中检测到高浓度的污染物，如营养物（氮、磷、有机物）、病原体（细菌和病毒）、盐、金属以及有机化学品，如多芳香族和石油碳氢化合物。数量的增加和质量的同时下降给雨水管理带来了若干挑战，一方面涉及有效收集和转移雨水以保护市政基础设施，另一方面涉及保护接收环境免受可能对人类和环境健康构成风险的潜在有毒水的影响。先前的研究已经确定了有希望的策略，当雨水在排放到环境中之前被收集在与卫生下水道分开的雨水下水道中时，提供初级处理，但是关于降水事件的时间动力学仍然未知，降水事件导致接收环境的脉冲暴露于高水平污染。萨斯卡通市是萨斯喀彻温省最大的城市。有一百多个独立的雨水下水道，其中许多未经处理直接排入南萨斯喀彻温河。以前的研究已经使人们更好地了解了流入河流的排放物，并帮助确定了进一步调查的主要排放物。然而，这项研究在调查排放物污染物的数量上是有限的，并且迫切需要可靠的数据来了解这些影响的时间动态。为了弥补这一差距，该研究项目将首次生成萨斯卡通市雨水质量的详细化学和毒理学概况。这项研究将对城市雨水对河流生态系统的污染风险进行更可靠的评估，并通过改善城市雨水管理，帮助该市为未来的法规做好准备。

Water originating from precipitation events and snowmelt runs off the urban landscape as stormwater and is collected in storm sewers. Increasing urbanization and sealing of soils have resulted in increased quantities of stormwater. At the same time, stormwater quality has dropped globally, and high concentrations of pollutants such as nutrients (nitrogen, phosphorus, organic matter), pathogens (bacteria and viruses), salts, metals, as well as organic chemicals such as polyaromatic and petroleum hydrocarbons have been detected in stormwater. These increases in quantity and concurrent decreases in quality result in several challenges for stormwater management related to the effective collection and diversion of stormwater to protect municipal infrastructure on the one hand, and protection of the receiving environment from potentially toxic waters that may pose a human and environmental health risks.Previous research has identified promising strategies to provide primary treatment of stormwater when it is collected in storm sewers that are separate from sanitary sewers prior to its release into the environment, but much remains unknown about the temporal dynamics of precipitation events that result in a pulsed exposure of the receiving environment to high levels of pollution. The City of Saskatoon is the largest municipality in Saskatchewan. There are over one hundred outfalls of separated storm sewers, many of which discharge directly into the South Saskatchewan River without treatment. Previous research has resulted in a better understanding of the discharges to the river and helped to identify key outfalls for further investigation. However, this research was limited in the number of investigated outfalls contaminants and, and reliable data to understand the temporal dynamics of these impacts are urgently needed. To bridge this gap, this research project will for the first time generate a detailed chemical and toxicological profile of stormwater quality in the City of Saskatoon. This research will result in a more reliable assessment of the risks of pollution from urban stormwater to the river ecosystem and help the City to prepare for future regulations through improved municipal stormwater management.