Author(s): T. Cochrane; L. Dasallas; B. Evans; M. Pahlow
Linked Author(s):
Keywords: Urban flood modelling; Transport risk analysis; Depth–velocity stability; Emergency planning
Abstract: Pluvial urban flooding due to large rainfall events poses severe risks to transport networks and public safety. This study presents an integrated framework using a 1D/2D flood model with a traffic simulation model to simulate urban flood dynamics and assess transport accessibility under hazardous conditions. The flood model provides high-resolution flood depth and velocity outputs, which are combined with stability functions for pedestrians and vehicles to identify high-risk zones. These risk maps are overlaid on the transport network to evaluate accessibility to critical services during floods. A case study in the central business district of Wellington, New Zealand, demonstrates that velocity-inclusive risk mapping significantly increases high-risk areas compared to depth-only assessments, with pedestrian risk zones increasing by over 80%. Transport network analysis reveals substantial reductions in accessibility to hospitals and public transport hubs during peak flooding. The proposed framework supports proactive emergency planning and resilience strategies by integrating hydraulic modelling with transport risk analysis. This approach offers a robust tool for cities facing climate-driven flood challenges. Further research is focusing on using machine learning to develop a surrogate flood model, allowing faster simulations (a few minutes for low resolutions modelling) and enabling prediction of mobility disruptions with real-time climate forecasts.
Year: 2026