Prioritizing Highway Restoration Following Flood Inundations: An Integrated Accessibility-Driven Approach

Climate change has led to increasing frequency and intensity of extreme weather events worldwide, making cities more vulnerable to urban flooding. While the direct impacts of flooding on safety and property damage have been extensively studied, the indirect effects of disrupted accessibility to essential facilities and services remain a critical yet under-addressed challenge. Current work often overlooks the complexity of geographical dependencies and the diverse nature of accessibility needs, leading to suboptimal flood mitigation efforts. This study proposes an integrated accessibility-driven framework for identifying critical flood hotspots and prioritizing flood mitigation interventions. The framework consists of three key components: (1) quantifying the importance of different facilities by considering residents’ diverse needs for urban services during flood conditions; (2) developing an integrated accessibility index that incorporates multiple facility types weighted by their importance; and (3) proposing a greedy restoration strategy that prioritizes the repair of flood hotspots based on their impact on the integrated accessibility. The proposed framework is demonstrated through a case study in the core urban area of Beijing. The results reveal that repairing flood hotspots based on their impact on integrated accessibility leads to a more rapid and effective recovery of regional accessibility compared to other strategies. A comparative analysis of different flood management strategies highlights the effectiveness of the proposed accessibility-based approach in guiding flood mitigation efforts. This research provides a quantitative tool for urban planners and decision makers to enhance the equity and resilience of urban systems in the face of increasing flood risks.