Assessment of Landslide susceptibility and risk to road network in Mt Elgon, Uganda

Abstract

Globally landslides occurrence is reportedly frequent particularly in the mountainous regions causing both direct and indirect effects to various sectors including the road transport. Landslides directly cause physical impact on the road network such as deposition of debris and impartial or total erosion of road segments. This leads to increased damage costs. Indirectly landslides cause disruption of the trade and movement whenever roads are blocked and alternative routes are resorted to. Existing literature reveals limited assessment of road vulnerability to landslides in the mountain regions in Africa. This study aimed at closing this information gap by investigating the risk to different segments of the road network in the Mt Elgon region. A fuzzy logic model was used to assess and map the landslide susceptibility into low, moderate, high and very high categories. The results reveal that mid to high altitude steep and rugged areas are more susceptible to landslides. The model performance was good as revealed by high AUC of 83%. Hotspot segments, which are high risk sections of the road network need to be prioritized for monitoring and risk mitigation.