Engineering School of Sustainable Infrastructure and Environment (ESSIE), University of Florida, 217 Black Hall, Gainesville, FL 32611, USA.
Water Res. 2012 Dec 15;46(20):6704-14. doi: 10.1016/j.watres.2011.12.039. Epub 2011 Dec 24.
Urban runoff is a resource for reuse water. However, runoff transports indicator and pathogenic organisms which are mobilized from sources of fecal contamination. These organisms are entrained with particulate matter (PM) that can serve as a mobile substrate for these organisms. Within a framework of additional treatment for reuse of treated runoff which requires the management of PM inventories in unit operations and drainage systems there is a need to characterize organism distributions on PM and the disinfection potential thereof. This study quantifies total coliform, Escherichia coli, fecal streptococcus, and enterococcus generated from 25 runoff events. With the ubiquity and hetero-dispersivity of PM in urban runoff this study examines organism distributions for suspended, settleable and sediment PM fractions differentiated based on PM size and transport functionality. Hypochlorite is applied in batch to elaborate inactivation of PM-associated organisms for each PM fraction. Results indicate that urban runoff bacterial loadings of indicator organisms exceed U.S. wastewater reuse, recreational contact, and Australian runoff reuse criteria as comparative metrics. All monitored events exceeded the Australian runoff reuse criteria for E. coli in non-potable residential and unrestricted access systems. In PM-differentiated events, bacteriological mobilization primarily occurred in the suspended PM fraction. However, sediment PM shielded PM-associated coliforms at all hypochlorite doses, whereas suspended and settleable PM fractions provide less shielding resulting in higher inactivation by hypochlorite.
城市径流是一种可再利用的水资源。然而，径流会携带从粪便污染源中迁移出来的指示生物和病原生物。这些生物与颗粒物质（PM）一起被夹带，而 PM 可以作为这些生物的可移动基质。在对处理后的径流进行额外处理以进行再利用的框架内，需要对 PM 库存进行管理，包括在单元操作和排水系统中管理 PM 库存，因此需要对 PM 上的生物分布及其消毒潜力进行特征描述。本研究量化了 25 次径流事件中产生的总大肠菌群、大肠杆菌、粪链球菌和肠球菌。由于 PM 在城市径流中的普遍存在和异质分散性，本研究根据 PM 大小和传输功能，对悬浮、可沉降和沉积物 PM 馏分中的生物分布进行了检查。次氯酸盐被分批应用于阐述每个 PM 馏分中 PM 相关生物的失活动力学。结果表明，城市径流中指示生物的细菌负荷超过了美国废水再利用、娱乐接触和澳大利亚径流再利用标准的比较标准。所有监测事件均超过了澳大利亚非饮用水住宅和无限制进入系统中对大肠杆菌的径流再利用标准。在 PM 区分的事件中，细菌的迁移主要发生在悬浮 PM 馏分中。然而，在所有次氯酸盐剂量下，沉积物 PM 都会对 PM 相关大肠菌群起到屏蔽作用，而悬浮和可沉降 PM 馏分的屏蔽作用较小，导致次氯酸盐的灭活效率更高。
