ASSESSING SLOPE STABILITY AND LANDSLIDE HAZARD IN CHAPIMA HEIGHTS, BLANTYRE DISTRICT

Landslide susceptibility is an important topic mainly because its geospatial analysis provides a useful tool for planning, disaster management, and hazard mitigation. In this study, the aim is to identify and analyze landslide susceptibility at a local spatial scale, which is Chapima Heights, Blantyre, using the multi-criteria evaluation (i.e., the analytical hierarchy process technique (AHP) and geographic information systems (GIS)). The following landslide conditioning factors were selected, representing the local terrain predispositions: slope angle, curvature, slope aspect, and elevation. The other factors are rainfall, normalized difference vegetation (NDVI), and land use. The raster-based analysis was conducted on data obtained. After the analysis maps for the chosen factors were created, they were classified and reclassified to risk levels to allow comparability and assigned weights using AHP according to their importance to contribute to the landslides class final map. The AHP results from this research show that the following were the percentages of the contributing factors: slope (42.44%), rainfall (23.84%), NDVI(12.64%), land use (8.67%), elevation (5.82%), aspect (3.89%), and curvature(2.7%). The final map shows that the majority of the area has low to moderate landslide susceptibility, with only the southwestern part being highly susceptible due to the steepness of the area. The validation of the results was based on consistency checks through the pairwise comparison of the chosen landslide contributing factors through consistency index and consistency ratio calculations that are 0.05094 and 0.03859, respectively. Finally, I will recommend people living in the southwest to build waterways that will direct the water to flow to safer sites therefore making almost the whole of the area safe in terms of landslide risks during periods of heavy rainfall.