Designing coupled LID–GREI urban drainage systems: Resilience assessment and decision-making framework

• Published in: The Science of the total environment Vol. 834; p. 155267
• Main Authors: Wang, Mo, Zhang, Yu, Bakhshipour, Amin E., Liu, Ming, Rao, Qiuyi, Lu, Zhongming
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 15.08.2022
• Subjects: Coupled system; Grey infrastructure; Life span; Low-impact development; Resilience; Urban hydrology; Low-impact development; Grey infrastructure; Coupled system; Life span; Urban hydrology; Resilience
• ISSN: 0048-9697; 1879-1026
• DOI: 10.1016/j.scitotenv.2022.155267

As flooding risks rise in urban areas, research suggests combining low impact development (LID) and grey infrastructure (GREI) in urban drainage systems. Several frameworks have been proposed to plan such coupled systems, but there is not a comprehensive framework to assess their resilience under diverse failure scenarios and sources of uncertainty. This study proposes a framework which considers both technological and operational resilience. Technological resilience has to do with the performance of the system under extreme loads. Operational resilience has to do with the performance and long-term efficiency of the system after structural damage or degradation, using appropriate probability distributions to quantify the likelihood of failures. The proposed framework is based on an optimization and multi-criteria decision-making platform. It improves on previous research, which lacked consideration of uncertainty in resilience over the life span. We also apply the proposed framework to a real-world test case, and find that in a high-density urban area, a coupled system is more cost-effective than GREI alone. Furthermore, decentralized systems with greater flexibility show significantly better technological and operational resilience. The proposed framework can better support decision-making for planning robust and cost-effective urban drainage systems, particularly in highly urbanized areas. [Display omitted] •A novel decision-making framework for hybrid decentralized urban drainage systems is proposed.•GREI structural failures and the long-term efficiency of LID are considered.•Coupled system is more cost-effective with better resilience in most scenarios.•Decentralized systems with higher flexibility have significantly better resilience.