Centre for Water Systems, College of Engineering, Mathematics and Physical Sciences, University of Exeter, North Park Road, Exeter, Devon, EX4 4QF, United Kingdom.
Centre for Water Systems, College of Engineering, Mathematics and Physical Sciences, University of Exeter, North Park Road, Exeter, Devon, EX4 4QF, United Kingdom.
Water Res. 2019 Feb 1;149:448-459. doi: 10.1016/j.watres.2018.11.025. Epub 2018 Nov 19.
Sustainability and resilience are both key considerations in the design and operation of wastewater systems. However, there is currently a lack of understanding of the relationship between these two goals and of the effects of increasing resilience on sustainability. This paper, therefore, presents a framework for analysis of the effects of resilience-enhancing interventions on sustainability, and applies this to an urban wastewater system. Given that sustainability addresses the long term, the framework includes a novel sustainability assessment approach which captures a continuum of potential future conditions and enables identification of tipping points where applicable. This method allows a wide range of potential futures to be captured whilst removing the need to develop scenarios or future projections. While it may be possible to develop interventions that are beneficial in terms of their effects on both resilience and sustainability, the results obtained from the case study demonstrate that implementing measures designed to increase resilience of an integrated urban wastewater system does not guarantee a universal improvement in sustainability. Therefore, when proposing measures to increase resilience, the potential effects on sustainability should be considered also. It is also shown that the extent of any negative effects on system sustainability can vary significantly depending on future conditions, with the case study intervention (increasing pump capacity) achieving the highest degree of sustainability if rainfall depths or imperviousness in the catchments reduce. However, trade-offs between sustainability indicators are present irrespective of future conditions. Furthermore, while an intervention that enhances resilience may be considered sustainable with respect to specific indicators under current conditions, tipping points exist and it will cease to be sustainable if future threat magnitudes exceed these.
可持续性和弹性都是废水系统设计和运行的关键考虑因素。然而，目前人们对这两个目标之间的关系以及提高弹性对可持续性的影响缺乏了解。因此，本文提出了一个分析增强弹性干预措施对可持续性影响的框架，并将其应用于城市废水系统。鉴于可持续性涉及长期问题，该框架包括一种新颖的可持续性评估方法，该方法可以捕捉潜在未来条件的连续体，并确定适用的临界点。这种方法可以在不需要开发情景或未来预测的情况下，捕捉到广泛的潜在未来。虽然有可能开发出对弹性和可持续性都有益的干预措施，但案例研究的结果表明，实施旨在提高综合城市废水系统弹性的措施并不能保证可持续性的普遍提高。因此，在提出提高弹性的措施时，也应考虑其对可持续性的潜在影响。结果还表明，任何对系统可持续性的负面影响的程度都可能因未来条件而异，案例研究中的干预措施（增加泵的容量）如果流域的降雨深度或不透水面积减少，则可以实现最高的可持续性程度。然而，无论未来条件如何，可持续性指标之间都存在权衡。此外，虽然增强弹性的干预措施在当前条件下可能被认为在特定指标上是可持续的，但如果未来威胁的程度超过这些，就会存在临界点，并且将不再可持续。
