A Dynamic Simulation Framework for Evaluating the Impacts of Urban Flooding on Transportation Systems

Abstract Road networks are a critical infrastructure system for the sustainable functioning of cities. However, they are frequently disrupted by urban flooding, leading to increased travel times and hindering emergency responses. This study proposed a novel dynamic flood–response simulation framework for urban transportation to evaluate the impacts of rainstorms and flooding on traffic systems, focusing on coupling the Integrated Hydrology and Hydrodynamics Urban Flood Model (IHUM) and the Simulation of Urban MObility (SUMO) model. The results obtained from Xiaoguwei Island, Guangzhou City, indicate that a 2-h rainstorm of a 2-year return period can affect traffic for over 4.5 h. During a 100-year return period rainstorm, average travel speed declines by 54%, while the emergency response time, for example, for police services, increases from 4.83 to 14.52 min. These findings highlight the significant impacts of flooding on urban traffic networks, assisting local authorities and stakeholders to proactively identify vulnerable network segments and prioritize targeted interventions for enhancing transportation system resilience to floods.