Treated wastewater is expected to constitute an essential part of the urban water cycle as an additional water resource in water-scarce or densely populated regions in the future. As decisions on the implementation of water recycling measures should always consider local conditions, the project ‘MULTI-ReUse: Modular treatment and monitoring for wastewater reuse’ has developed a comprehensive sustainability assessment tool, designed to support decision-makers in examining the technical feasibility, economic viability, ecological compatibility and social acceptance of alternative service water supply solutions at local level. This article describes the structure of this sustainability assessment tool and its underlying multi-criteria assessment approach based on 23 evaluation criteria. Already in the development phase, the tool was tested in a German and a Namibian case study. Both case studies are presented with a special focus on the technologies used and the results of the analysis with the sustainability assessment tool. Case study testing proved that the tool is applicable in various environmental and societal settings with widely differing climatic conditions, limited resource availability, for varying feed water qualities and water quality requirements. The comprehensive, straightforward assessment approach enabled the local users to identify the most sustainable supply system or strategy for their decision case.

预计未来处理后的废水将构成城市水循环的重要组成部分，作为缺水或人口稠密地区的额外水资源。由于执行水循环利用措施的决定应始终考虑当地情况，因此“多重再利用：废水回用的模块化处理和监测”项目开发了一种全面的可持续性评估工具，旨在支持决策者检查技术可行性，经济可行性，生态兼容性和社会对地方替代服务供水解决方案的接受程度。本文介绍了此可持续性评估工具的结构及其基于23个评估标准的潜在多标准评估方法。已经处于开发阶段，该工具已在德国和纳米比亚的案例研究中进行了测试。这两个案例研究都特别关注使用的技术和可持续性评估工具的分析结果。案例研究测试证明，该工具适用于各种环境和社会环境，气候条件差异很大，资源有限，可满足各种给水水质和水质要求。全面，直接的评估方法使本地用户能够为其决策案例确定最可持续的供应系统或策略。案例研究测试证明，该工具适用于各种环境和社会环境，气候条件差异很大，资源有限，可满足各种给水水质和水质要求。全面，直接的评估方法使本地用户能够为其决策案例确定最可持续的供应系统或策略。案例研究测试证明，该工具适用于各种环境和社会环境，气候条件差异很大，资源有限，可满足各种给水水质和水质要求。全面，直接的评估方法使本地用户能够为其决策案例确定最可持续的供应系统或策略。