A multi-criteria GIS model for geohazard assessment in the Charvak reservoir area, Uzbekistan

Mountainous reservoir regions are particularly susceptible to geohazards due to steep topography, fractured lithologies, active faults, and seasonal hydrological fluctuations. The Charvak basin in northeastern Uzbekistan, designated as a Free Tourist Recreation Zone, is increasingly affected by expanding infrastructure and tourism, which increases exposure to natural hazards. This study presents the first integrated geohazard susceptibility map of the Charvak basin using remote sensing and multi-criteria GIS analysis. A GIS-based model was developed to evaluate slope-related hazards—landslides, debris flows, and rockfalls—based on six indicators: slope gradient, lithological strength, lineament density, Normalized Difference Water Index (NDWI), distance to active faults, and distance to the reservoir shoreline. The indicators were weighted using the Analytic Hierarchy Process (AHP), with slope gradient (0.28) and lineament density (0.24) identified as dominant factors. The resulting composite index was validated through comparison with landslide and debris flow inventories as well as seismicity data. The susceptibility map indicates that ∼19 % of the basin falls into high and very high hazard classes, while ∼48 % is classified as low to very low. High-susceptibility zones overlap substantially with infrastructure, including 21 % of villages and tourism facilities and 27 % of the road network. These findings provide a spatial basis for risk-informed land-use regulation, infrastructure planning, and disaster management in the Charvak region. More broadly, the study demonstrates the effectiveness of combining remote sensing and multi-criteria GIS methods for geohazard assessment in other mountainous and data-limited environments.