Rainwater and Snowmelt Harvesting Suitability in Chitral, Eastern Hindu Kush, Pakistan

Water scarcity has emerged as a major environmental challenge in rain shadow regions of mountainous areas worldwide. The Hindu Kush–Karakorum–Himalaya, although recognized as one of the world’s major “water towers”, is experiencing increasing water scarcity due to climate change and rapid population growth, threatening ecosystems, economies, and livelihoods. The Chitral River basin in northwestern Pakistan is a snow-dominated watershed where meltwater and seasonal precipitation generate substantial runoff during spring, followed by prolonged periods of acute water scarcity. Water harvesting represents a potential strategy for sustainable water resource management in this region. This study employed a hybrid approach combining Multi-Criteria Decision Analysis (MCDA), based on Analytical Hierarchy Process (AHP), with geospatial techniques to identify potentially suitable locations for rainwater and snowmelt harvesting (RSH). The results indicate that Chitral can be divided into four RSH suitability classes: very highly suitable (19.1%), highly suitable (43.8%), moderately suitable (22.1%), and less/non-suitable (15.0%). Evaluation of the suitability map using existing water-harvesting structures, satellite imagery, field observations, and expert and local resident interviews demonstrated the robustness of the methodology. The findings provide a spatial framework to support stakeholders in identifying suitable sites for RSH and contribute to the scientific basis for sustainable water management and climate change adaptation. The approach can also be adapted to other mountainous basins with similar hydroclimatic and geomorphological characteristics.