Study on Resilience Assessment and Influencing Factors of Urban Flooding in Beijing-Tianjin-Hebei Urban Agglomeration

In the context of global climate change, urban flooding disasters are frequent, posing challenges to traditional disaster prevention models. This study focuses on the Beijing-Tianjin-Hebei city cluster and constructs a resilience assessment system for urban flooding based on resilience theory, incorporating 20 indicators from three dimensions: stress, state, and response. Using the entropy weight method-improved TOPSIS model and obstacle degree model, this study dynamically evaluates and analyzes the factors influencing urban flooding resilience in the Beijing-Tianjin-Hebei region from 2019 to 2023. The findings are as follows: (1) The comprehensive index of urban flooding resilience in the Beijing-Tianjin-Hebei region increased from 0.484 in 2020 to 0.736 in 2024, showing a three-stage evolution characterized by "foundation reconstruction-bottleneck adjustment-system breakthrough"; (2) The stress impact value decreased by 33.8%, thanks to source reduction and pipeline upgrades; the state impact value increased by 265%, due to the widespread use of permeable pavements and green space water storage projects; the response impact value rose by 136%, supported by intelligent monitoring and emergency system construction; (3) Adaptability to extreme weather remains a weak point, with the negative ideal solution index peaking at 0.946 in 2022. Recommendations include optimizing ecological space (increasing the proportion of green space retention areas to 20%), upgrading drainage facilities for once-in-a-century events, and enhancing regional collaborative governance to strengthen resilience. This study provides a quantitative analysis framework and practical approach for urban flooding management in megacity clusters.