A flood risk assessment framework for urban subway systems: A case study in Beijing, China

Authors

• Wenqi Wu
• Zhongfan Zhu
• Xinyu Zheng
• Shuyou Liu
• Dawei Zhang
• Dingzhi Peng
• Bo Pang

Document Type

Journal Article

Publication Date

2025

Subject Area

place - asia, place - urban, mode - subway/metro, land use - impacts, planning - methods

Keywords

Urban subway, flood risk

Abstract

Within the context of climate change and urbanization, there are several hazard events in which surface floodwater pours into urban underground spaces, particularly subway systems, leading to notable losses of life and property worldwide. Therefore, the implementation of flood risk assessments for urban subway systems is becoming urgent. In this study, we proposed a novel framework for evaluating subway flood risks by comprehensively considering the hazard, exposure, vulnerability and coping capacity of subway systems for urban flooding. The Beijing subway system was chosen in a case study. Three hazard indicators, eight exposure indicators, five vulnerability indicators and seven coping capacity indicators, were incorporated into a multi-index framework. The flood risk levels of each subway line and subway station were obtained. Furthermore, Pearson’s correlation analysis and random forest (RF) regression combined with the SHapley Additive exPlanations (SHAP) method were adopted to reveal the correlation between each evaluation indicator and the flood risk level and quantify their contributions to the change in flood risk. The findings revealed that for the Beijing subway system, the highest- and high-risk zones accounted for 26.16% of the total subway area. The top ten flood risk stations were located mainly in the central urban area. Compared with the traditional assessment framework, incorporating coping capacity indicators into the framework decreased subway flood risk levels in many districts of Beijing. Among all indicators, passenger flow, node degree, betweenness centrality, subway line density and subway line proximity play important roles in determining the subway flood risk. This study offers a new framework for urban system flood risk assessment and provides reference data for flood risk prevention and control of urban subway systems within the context of resilient city construction.

Rights

Permission to publish the abstract has been given by Elsevier, copyright remains with them.

Comments

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http://www.sciencedirect.com/science/journal/22106707

Recommended Citation

Wu, W., Zhu, Z., Zheng, X., Liu, S., Zhang, D., Peng, D., & Pang, B. (2025). A flood risk assessment framework for urban subway systems: A case study in Beijing, China. Sustainable Cities and Society, 106681.