Evaluating microbial risks and performance criteria for safe management of stormwater and rainwater use in Alberta

艾伯塔省面临着水质和稀缺问题。雨水和雨水是能够补充日益增长的用水需求的替代水源，但也受到以下问题的困扰：i)管道基础设施老化；ii)设计方面的挑战(如合并下水道排污口、非法交叉连接)；iii)缺乏北美病原体相关的安全回用标准；iv)缺乏关于病原体/污染物浓度的科学数据以评估风险；v)艾伯塔省和加拿大缺乏或相互矛盾的监管政策框架。这些挑战阻碍了在全省范围内采用监管框架。由于水传播的病原体代表着严重的风险，我们建议与市政当局(卡尔加里和艾德瑞)合作，评估与雨水和雨水再利用相关的微生物风险。将收集来自雨水和雨水系统的水样，并进行微生物病原体(病毒、细菌、原生动物、蠕虫)和常规微生物水质指标(大肠杆菌、大肠菌群)的分析。将进行微生物来源追踪，以确定影响这些系统的污染源。这些数据与其他物理化学参数(降水、排水流量、土地利用等)一起，将被用来模拟病原体在雨水系统中的传输，以评估微生物负载。这些数据将被输入定量微生物风险评估(QMRA)框架，以评估各种再利用方案(例如灌溉、冲厕所等)下的水安全，以及为满足风险目标而确定的处理水平。这些信息还将用于制定水安全计划，以管理病原体风险。该项目将从根本上为监管发展提供基于科学的证据，从而有助于在加拿大发展和支持可持续的水再利用。除了减少对饮用水供应的依赖和降低与基础设施扩建相关的成本外，对加拿大社会的好处还包括干旱控制、长期供水管理、降低城市的生态足迹，以及为应对加拿大市政当局的城市挑战提供可持续的做法。

Alberta is faced with water quality and scarcity issues. Stormwater and rainwater are alternative water sources that can supplement growing water demands, but are plagued by: i) aging pipe infrastructure; ii) design challenges (i.e., combined sewer outfalls, illicit cross-connections); iii) the absence of North American pathogen-related criteria for safe reuse; iv) a lack of scientific data on pathogen/contaminant concentrations to estimate risks; and v) a lack of, or conflicting, regulatory policy framework in Alberta and Canada. These challenges have impeded the adoption of a province-wide regulatory framework. Since waterborne pathogens represent an acute risk, we propose to work with municipalities (Calgary and Airdrie) on evaluating the microbial risks associated with stormwater and rainwater reuse. Water samples from stormwater and rainwater systems will be collected and analyzed for microbial pathogens (viruses, bacteria, protozoans, helminths) and routine microbial water quality targets (E. coli, coliforms). Microbial source tracking will be done to identify sources of pollution impacting these systems. This data, along with other physicochemical parameters (precipitation, drainage flow, land-use, etc.), will be used to model pathogen transport in stormwater systems for evaluating microbial loading. The data will be fed into quantitative microbial risk assessment (QMRA) frameworks to evaluate water safety in terms of 'water-fit-for-purpose' under a variety of reuse scenarios (e.g., irrigation, toilet flushing, etc.), and the level of treatment determined for meeting risk targets. The information will also be used to develop water safety plans to manage pathogen risks. The project will be instrumental in developing and supporting sustainable water reuse in Canada by fundamentally grounding science-based evidence in regulatory development. In addition to decreasing dependency on potable supplies and reducing costs associated with infrastructure expansion, the benefits to Canadian society include drought control, long-term water supply management, lowering the ecological footprints of cities, and providing sustainable practices to support urban challenges in Canada's municipalities.