Impacts of Climate Variability and Urban Expansion on Groundwater Systems in Mansehra

Abstract

Groundwater serves as the principal source of domestic water supply in Mansehra District, Khyber Pakhtunkhwa, Pakistan. However, rapid urbanization and climate change have increasingly impacted groundwater quality and recharge dynamics in the region. This study investigates groundwater quality and identifies potential recharge sources under shifting environmental conditions. A total of eleven water samples were collected from wells, rivers, and surface channels across five distance-based zones (0–200 m, 201–400 m, 401–600 m, 601–800 m, and 801–1000 m) relative to the nearest river. The samples were taken in sterile, dry containers and were transported within 24 hours to the Pakistan Council of Research in Water Resources (PCRWR), Islamabad, for detailed physicochemical analysis. Parameters measured included pH, electrical conductivity (EC), total hardness, alkalinity, turbidity, calcium (Ca), and potassium (K). The findings show extensive groundwater quality deterioration in areas subject to high urban activity and climatic fluctuation. More specifically, samples from Baffa showed higher hardness, Ca, and K levels above WHO allowable limits, indicating contamination potential. On the other hand, samples from Nokot and Ichria mostly met WHO standards, with turbidity being the only parameter of concern. Comparison of analyses of well, river, and pond samples revealed rivers and surface water bodies as the preeminent sources of groundwater recharge. The findings highlight the imperative need for sustainable groundwater management practices to mitigate the adverse impacts of anthropogenic stresses and climate change in the Mansehra Basin.