Evaluating the slope stability on shallow landslide using geographic information system (GIS)

Landslides are natural disasters that have potential to severely hurt a country's economy. In Malaysia, many conventional roads are constructed across mountainous terrain, where landslides on man-made embankments or roadside cut slopes have disrupted critical transportation networks and resulted in property loss, fatalities, infrastructure damage, and community displacement, thereby worsening the economic impacts. Although several studies have assessed landslide losses using different approaches, limited research has focused on how groundwater development affects slope stability due to the complex nature of landslides and their diverse geological settings. Therefore, this study aims to evaluate slope stability and generate a Factor of Safety (FOS) map for shallow landslides along roadside slopes in Cameron Highlands using a Geographic Information System (ArcGIS). FOS values range from 0.6–3.2 for fully saturated conditions, 0.9–4.3 for partially saturated conditions, and 1.2–5.6 for dry conditions. The fully saturated state indicates unstable slopes within the study area, and a significant decrease in FOS occurs when transitioning from dry to saturated conditions. The landslide susceptibility map also shows high hazard levels along Jalan Simpang Pulai with FOS between 0.6 and 0.8 due to rising groundwater levels. Overall, the developed FOS maps support land-use planning and landslide risk mitigation.