Landslide Susceptibility Mapping Using GIS-Based Multicriteria Decision Analysis: A Case Study of Lokoja, Nigeria

Located between rivers and hills, Lokoja’s development is advancing into hilly areas due to limited flat and safe land without recourse to the stability of the hills. The study aims to assess the structural stability of hilly areas through the production of landslide susceptibility maps using both a Geographic Information System and an analytical hierarchy process (AHP) model. Twelve data layers are exploited as the conditioning factors to detect the most susceptible areas. These factors include slope, aspect, plan curvature, land use and land cover, lithology, topographic wetness index, stream power index, distance to road, distance to stream, slope length, and fault. Subsequently, a Landslide susceptibility map was produced using a precise and conclusive weighted-overlay analysis of the AHP pair-wise evaluation methodologies to evaluate the effects of the conditioning factors. Results indicate that 5,703 hectares (32.34%) of the study area are ‘not susceptible’, 7,881 hectares (44.69%) are ‘moderately susceptible’, and 4,051 hectares (22.97%) are ‘highly susceptible’ to landslides. The study concludes that the susceptibility model is reliable for future decision-making, urban planning, and development in Lokoja, Kogi State, to reduce the risk of landslides in the region.