Predicting groundwater potential zones in Upper Thal Doab, Indus Basin through integrated use of RS and GIS techniques and groundwater flow modeling

Abstract

In Pakistan, groundwater contributes about 40% in total water resources of the country and is considered a great source of fresh water which plays vibrant role in sustainability of irrigated agriculture. It is critical to safe and properly manage groundwater resources of the country for sustainable use. To ascertain groundwater potential areas and current status of the aquifer in the Upper Thal Doab, a part of Indus Basin in the Punjab Plain, an integrated approach of remote sensing (RS), Geographic Information System (GIS), and groundwater modeling has been adopted. Different input data sets like, geology, geomorphology, rainfall, land use/land cover, elevation, and drainage were overlaid and weighted to prepare groundwater potential zones map. The results classify the groundwater potential zones into three categories: good, moderate, and poor. The results demonstrate that about 12% of the study area is designated as good, 27% moderate, and 61% as poor. The groundwater modeling of the area was also carried out to find the current status of the aquifer, favorable sites for groundwater and predict future scenarios. The steady-state model was calibrated with the hydrological conditions of 1984 when the hydraulic heads were appeared to be in equilibrium condition. Transient simulations were calibrated for six stress periods with varying lengths commencing from 1985 to 2025. The mass balance analysis for transient model shows that the total outflows gradually increases than inflows from 1991 onwards due to increase in water extraction through water wells. The results demand to conduct periodic studies of the area to monitor the groundwater resources depletion if any in due course of time for timely management and precautionary measures.