Environmental and Public Health Microbiology Laboratory (EPHM Lab), Monash Infrastructure Research Institute, Department of Civil Engineering, Monash University, VIC 3800, Australia.
Environmental and Public Health Microbiology Laboratory (EPHM Lab), Monash Infrastructure Research Institute, Department of Civil Engineering, Monash University, VIC 3800, Australia; School of Civil and Environmental Engineering, UNSW, Sydney, NSW 2052, Australia.
Water Res. 2018 Mar 15;131:218-227. doi: 10.1016/j.watres.2017.12.045. Epub 2017 Dec 21.
Stormwater constructed wetlands are not well characterised for their ability to remove pathogens which can pose public health risks during stormwater harvesting activities. This study investigated the behaviour of faecal indicator organism Escherichia coli (E. coli) and reference pathogen Campylobacter spp. in stormwater constructed wetlands, using a case study system located in Melbourne, Australia. Grab sampling and event-based monitoring revealed influent concentrations of E. coli were typical of other urban stormwater studies, yet Campylobacter concentrations were orders of magnitude above those urban stormwater studies used to develop the Australian Guidelines for Water Recycling, reached levels typical of raw domestic wastewater. The wetland consistently removed E. coli from stormwater (mean log removal 0.96, range 0.19-1.79), while Campylobacter spp. concentrations were often higher in outflow than inflow (mean log removal 0.05, range -0.9-1.25). These results indicate that E. coli is a poor indicator for this reference pathogen. The log reductions of both organisms also failed to meet the criteria specified for any end-use, as listed in the Australian Guidelines for Water Recycling, suggesting further treatment is required prior to harvesting. Finally, this study proposed that direct faecal deposition by waterfowl faeces was a microbial source to stormwater wetlands and that this was partly responsible for the varied microbial removal rates observed. Overall, this work validates the need for further characterisation of pathogens in raw urban stormwater, and the ability for water sensitive urban design features, such as wetlands, to remove both indicator and pathogenic microorganisms.
雨水人工湿地对于去除病原体的能力尚未得到充分研究，而这些病原体在雨水收集活动期间可能会对公共健康构成风险。本研究以位于澳大利亚墨尔本的案例研究系统为对象，调查了粪便指示生物大肠杆菌（E. coli）和参考病原体弯曲菌（Campylobacter spp.）在雨水人工湿地中的行为。 定点采样和基于事件的监测表明，大肠杆菌的进水浓度与其他城市雨水研究相似，但弯曲菌的浓度比用于制定澳大利亚水再利用指南的城市雨水研究高出几个数量级，达到了典型的原生生活污水水平。湿地始终能从雨水中去除大肠杆菌（平均对数去除率为 0.96，范围为 0.19-1.79），而弯曲菌的浓度在出水中通常高于进水（平均对数去除率为 0.05，范围为-0.9-1.25）。这些结果表明，大肠杆菌是该参考病原体的不良指示物。这两种生物的对数减少率也未能满足澳大利亚水再利用指南中列出的任何最终用途的标准，这表明在收获之前需要进行进一步的处理。最后，本研究提出，水禽粪便的直接粪便沉积是雨水湿地中微生物的来源，这也是观察到不同微生物去除率的部分原因。 总的来说，这项工作验证了需要进一步研究原始城市雨水中的病原体，以及水敏感城市设计特征（如湿地）去除指示生物和致病微生物的能力。
