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Sci Total Environ. 2012 Nov 1;438:541-8. doi: 10.1016/j.scitotenv.2012.08.062. Epub 2012 Oct 4.
Stream flow augmentation with recycled water has the potential to improve stream habitat and increase potable water supply, but the practice is not yet well understood or documented. The objectives of this report are to present a short review illustrated by a case study, followed by recommendations for future stream flow augmentation projects. Despite the fact that wastewater discharge to streams is commonplace, a water agency pursuing stream flow augmentation with recycled water will face unique challenges. For example, recycled water typically contains trace amounts of organic wastewater-derived compounds (OWCs) for which the potential ecological risks must be balanced against the benefits of an augmentation project. Successful stream flow augmentation with recycled water requires that the lead agency clearly articulate a strong project rationale and identify key benefits. It must be assumed that the public will have some concerns about water quality. Public acceptance may be better if an augmentation project has co-benefits beyond maintaining stream ecosystems, such as improving water system supply and reliability (i.e. potable use offset). Regulatory or project-specific criteria (acceptable concentrations of priority OWCs) would enable assessment of ecosystem impacts and demonstration of practitioner compliance. Additional treatment (natural or engineered) of the recycled water may be considered. If it is not deemed necessary or feasible, existing recycled water quality may be adequate to achieve project goals depending on project rationale, site and water quality evaluation, and public acceptance.
再生水补充河道流量具有改善河道生境和增加饮用水供应的潜力，但该实践尚未得到很好的理解或记录。本报告的目的是通过案例研究进行简要回顾，并为未来的河道流量补充项目提出建议。尽管向河道排放废水是很常见的，但追求用再生水补充河道流量的水务机构将面临独特的挑战。例如，再生水通常含有痕量的有机废水衍生化合物（OWCs），必须在补充项目的效益与潜在的生态风险之间取得平衡。成功地用再生水补充河道流量要求主导机构明确阐述强有力的项目理由，并确定关键效益。必须假设公众对水质会有一些担忧。如果补充项目除了维持河道生态系统之外还有其他共同效益，例如提高供水系统的供应和可靠性（即饮用水抵消），公众接受度可能会更高。监管或项目特定的标准（优先 OWCs 的可接受浓度）将能够评估生态系统的影响，并证明从业者的合规性。可能需要考虑对再生水进行额外的处理（自然或工程）。如果认为没有必要或不可行，那么根据项目的基本原理、场地和水质评估以及公众接受程度，现有的再生水质量可能足以实现项目目标。
