Numerical Groundwater Modeling for Sustainable Management of the Kabul Urban Aquifer

Groundwater is the primary source of water for drinking, agriculture, and industry in Kabul City. Understanding groundwater dynamics and predict future stresses on the groundwater system of Kabul aquifer is crucial for the effective and sustainable use, and management of the aquifer. A comprehensive dataset introduced to MODFLOW code using GMS interface was employed to simulate groundwater flow model in Kabul aquifer in steady state and transient conditions. The simulated groundwater flow shows that the main sources of water entering the aquifer are recharge from rivers, infiltration from precipitation, inflow from nearby aquifers, and return flow from pumping. Water mainly leaves the aquifer through pumping and by flowing into nearby aquifers. The simulated groundwater budget shows a negative balance (- 24.89 million m3 per year) between recharge and discharge in the plain. This study uses groundwater modeling to assess the aquifer system in the Kabul Plain with greater accuracy. The result of invers groundwater modeling shows that hydraulic conductivity ranges from 0.2 meters per day in low-permeability areas to 197.83 meters per day near rivers and the Logar aquifer. The aquifer is anisotropic, meaning its properties vary with direction, and the specific yield ranges from 0.33% to 34.99%. The results of calibrated model show that by 2035 the groundwater level will sharply decline under the present conditions across the plain. Analysis of the different scenarios indicates that with a 50% reduction in groundwater abstraction, the groundwater level will rise to 8.0 m by 2035 on average. Additionally, artificial recharge from surface water, including precipitation and riverbank infiltration, could increase the groundwater level by up to 5.7 meters by 2035. The findings present optimistic scenarios for the current and future sustainability of groundwater resources in Kabul Plain. The research establishes an essential realization of Kabul Plain' groundwater dynamics. This study provides strategic insights for effective groundwater resources management in response to current and future stresses on groundwater system.