Mitigating the vulnerability of critical transportation infrastructure to flooding

Abstract

This study examines the vulnerability of critical road infrastructure to flooding and proposes mitigation measures to enhance resilience and protect the River Nabuyonga sub catchment in Mbale city. This was because the immediate impact of floods specifically in urban areas was on the transport system. The study employed an integrated methodology, combining rainfall analysis, hydrologic modeling, and hydrodynamic modeling using software like Personal Computer Storm Water Management Model (PCSWMM) to investigate the hydrological responses in the River Nabuyonga sub catchment with precipitation data and the Digital Elevation Model (DEM) as input to obtain design discharge, HEC-RAS for obtaining flood maps and ArcGIS delineation of the catchment to assess the susceptibility of key transportation assets to varying flooding scenarios. By analyzing historical rainfall data and simulating potential future inundation events, the research identified vulnerable areas, assets and evaluated their criticality to flooding. Most of the studies on transport vulnerability consider topographic properties along with supply and demand side of transport system to access the disruption, but less attention is given to the potential impacts of weather extremes on the performance of transportation network. With that established, therefore, this research was conducted to bridge these critical knowledge gaps by assessing the specific vulnerabilities of its critical infrastructure to flood events, this study seeks to generate a better understanding of the risks faced by the city.