Landslide Susceptibility Index and Network Mapping for Spotting the Affected and Alternative Planning Routes

Abstract

Millions of people were harmed by landslides, and many have lost their lives. Instead of widening the access road during a landslide, an alternative or new road should be introduced accurately. This study was conducted to determine an appropriate GIS-based alternative planning route during landslides in Ranau, Sabah, Malaysia. For determining the criteria weights of the landslide, a GIS-based Multi-Criteria Decision Making (GIS-MCDM) technique was utilised with the extension of the Analytical Hierarchy Process (AHP). The Landslide Susceptibility Index (LSI) map was created using lithology, slope, aspect, rainfall, land use or land cover (LULC), and proximity to a stream. The map was compared with the NASA-landslide historical data for the verification. The study found that lithology, slope, and aspect were the most contributing factors to the local landslide occurrences. The route from Pinausuk to the destination position of Kundasang is the most appropriate choice. An alternative planning route map is a helpful tool for the authorities and it might be also made available to the public, so they will know which path can be taken for more secure alternative access during landslides.