Rainfall and Groundwater Relationship Assessment in the North River Basin, Afghanistan

Abstract

Rainfall and groundwater variability are critical for sustainable water-resource management in arid and semi-arid regions like Afghanistan. This study investigates the relationship between precipitsation and groundwater levels in the North River Basin, using long-term rainfall data (1979–2022) from 13 meteorological stations and groundwater observations from 216 wells across five sub-river basins during 2022–2023. Descriptive statistics and the Precipitation Concentration Index (PCI) were applied to assess temporal rainfall patterns, seasonal variability, and rainfall concentration. Groundwater trends were analyzed by comparing monthly and annual fluctuations in water-table levels. Results indicate a decline in precipitation from 1979–1999, followed by gradual recovery after 2000, with rising rainfall concentration in recent decades, particularly in the dry season. Groundwater data reveal significant fluctuations across the sub-river basins, with some areas experiencing drawdown, likely due to over-extraction or insufficient recharge. Correlation analysis highlights the influence of rainfall variability on groundwater levels, demonstrating the importance of understanding seasonal recharge dynamics. These findings provide insights into the coupling between rainfall and groundwater, offering valuable information for water-resource planning, drought mitigation, and sustainable management of aquifers in the North River Basin.