A Topology-Based Approach for Vulnerable Pipe Identification and Modification in an Urban Drainage Network

To improve the performance of urban drainage networks (UDNs), it is crucial to identify pipes that are most affected by overflows. This study applied a topology-based approach to identify vulnerable pipes, considering their connectivity, physical characteristics, and the influence of upstream and downstream pipes. The reliability of the proposed method was tested using part of the drainage network in Ahvaz City as a case study. The vulnerability assessment results were used to develop a pipe modification strategy, considering pipe replacement costs to evaluate effectiveness in improving network performance. The vulnerable pipes identified by topological analysis were compared with those determined through hydraulic simulations based on the hourly capacity limit (HCL), showing a strong correlation (correlation coefficient=0.83, p<0.001). The pipe modification strategy achieved a 28% reduction in total HCL and nearly a 31% reduction in maximum HCL. The results show that the topology-based network modification approach provides valuable guidance for formulating strategies aimed at improving UDN performance.