Water scarcity, either due to increased urbanisation or climatic variability, has motivated societies to reduce pressure on water resources mainly by reducing water demand. However, this practice alone is not sufficient to guarantee the quality of life that high quality water services underpin, especially within a context of increased urbanisation. As such, the idea of water reuse has been gaining momentum for some time and has recently found a more general context within the idea of the Circular Economy. This paper is set within the context of an ongoing discussion between centralized and decentralized water reuse techniques and the investigation of trade-offs between efficiency and economic viability of reuse at different scales. Specifically, we argue for an intermediate scale of a water reuse option termed ‘sewer-mining’, which could be considered a reuse scheme at the neighbourhood scale. We suggest that sewer mining (a) provides a feasible alternative reuse option when the geography of the wastewater treatment plant is problematic, (b) relies on mature treatment technologies and (c) presents an opportunity for Small Medium Enterprises (SME) to be involved in the water market, securing environmental, social and economic benefits. To support this argument, we report on a pilot sewer-mining application in Athens, Greece. The pilot, integrates two subsystems: a packaged treatment unit and an information and communications technology (ICT) infrastructure. The paper reports on the pilot's overall performance and critically evaluates the potential of the sewer-mining idea to become a significant piece of the circular economy puzzle for water.

无论是由于城市化程度的提高还是由于气候变化造成的水资源短缺，都促使社会主要通过减少水需求来减轻对水资源的压力。但是，仅凭这种做法不足以保证高质量水服务所支撑的生活质量，尤其是在城市化进程日益加快的情况下。因此，中水回用的思想已经流行了一段时间，并且最近在循环经济的思想中找到了更普遍的背景。本文是在集中式和分散式中水回用技术之间正在进行的讨论以及不同规模中中水回用效率与经济可行性之间权衡取舍的背景下进行研究的。具体来说，我们主张将中水回用方案称为“下水道开采”的中间规模，可以认为是邻域规模的重用方案。我们建议下水道采矿（a）在废水处理厂的地理位置存在问题时提供一种可行的替代性再利用选择，（b）依靠成熟的处理技术，并且（c）为中小型企业（SME）提供参与的机会在水市场上，确保环境，社会和经济利益。为了支持这一论点，我们报告了希腊雅典的一个下水道采矿试点应用。该试点项目集成了两个子系统：一个包装的处理单元和一个信息和通信技术（ICT）基础架构。该论文报告了飞行员的整体表现，并严格评估了下水道开采想法成为循环水难题中重要一环的潜力。