Stress-Testing Road Network in Great Britain with Historical Flood Events between 1953-2024

Abstract

Road infrastructure is facing increasing flooding risks, causing asset damage and disrupting traffic flows. Effective risk management requires integrated assessments that capture road vulnerability, disruption and recovery. While localised studies highlight spatial variations in traffic disruptions, national-scale assessments have largely focused on flood exposure rather than systemic disruption analysis allowing for stress-testing the network’s capabilities. To address these gaps, we developed a modelling framework combining a process-based flow model of passenger travel-to-work commuter flows and applied it to stress-test Great Britain’s road networks against 17 historical flood events (1953–2024). Results reveal significant variations between direct and indirect damage losses, with major A roads and suburban bridges emerging as critical points. Notably, indirect losses due to increased journey rerouting costs can be significantly higher than direct damages depending upon the hazard event. The model is generalisable and can be applied to stress-test other road networks and flood scenarios globally.

Published: 20 June 2025