Safe water reuse usually means the provision of reclaimed water with its quality meeting the criteria for safeguarding human health and aquatic ecology. Regarding this, people often overstress the technological magic in terms of hazardous substances removal by engineered processes while ignoring the utilization of nature's power to provide an additional barrier for safety control. Based on an understanding of the function of the hydrological cycle to secure water quality and the fact that water reuse is through a water loop, the author presented his viewpoint on creating a quasi-natural water cycle for water reuse. Existing data showed the remarkable effects of emerging pollutants removal and associated reduction of biotoxicities from the reclaimed water during open-storage under a quasi-natural condition. Adsorption by soil particles, sunlight-induced photolysis and purification by aquatic life were thought to be the major actions contributing to effective water quality improvement in a quasi-natural manner. Safe water reuse through a quasi-natural water cycle can thus be a recommendable strategy for system design in accordance with the purposes of water use.

安全的中水回用通常是指提供水质符合保障人类健康和水生生态标准的再生水。对此，人们往往过分强调通过工程工艺去除有害物质的技术魔力，而忽视了利用大自然的力量为安全控制提供额外的屏障。基于对水文循环确保水质的功能的理解以及水循环利用这一事实，作者提出了他对建立一个准自然水循环的水循环利用的观点。现有数据表明，在准自然条件下露天储存期间，再生水中的新兴污染物去除和相关降低生物毒性的显着效果。被土壤颗粒吸附，阳光引起的光解和水生生物的净化被认为是有助于以准自然方式有效改善水质的主要行动。因此，根据用水目的，通过准自然水循环实现安全的水再利用可以成为系统设计的推荐策略。