ABSTRACT
Landslides are a major geohazard in Nepal's mountainous regions, frequently triggered by intense monsoonal rainfall, seismic activity, and unregulated infrastructure development. This study investigates the slope stability of the Khamvitta landslide (28°31′40″N, 83°39′16″E) along the Kaligandaki Corridor, located within the Lesser Himalayan Sequence. An integrated assessment combining Electrical Resistivity Tomography (ERT) with detailed geotechnical investigations: both field and laboratory-based was conducted. The site comprises high-grade metamorphic bedrock overlain by colluvial deposits, shallow groundwater (~1.5 m), and low-cohesion soils (5–13 kPa), with multiple observed slip surfaces. Slope stability analysis yielded a Factor of Safety (FoS) of 1.071, which is below the generally accepted threshold of 1.3, indicating a condition of marginal stability. The results suggest that anthropogenic factors, particularly unregulated construction activities, were the primary contributors to slope failure. This integrated approach underscores the importance of coupling geophysical and geotechnical methods for reliable slope hazard assessment in Himalayan terrains.
