Evaluation of the hydrochemistry of groundwater at Jhelum Basin, Punjab, Pakistan

This study investigates the hydrochemistry of the Mandi Baha-Ud-Din district, which is an important part of the Jhelum Basin. The study area is highly populated with low facilities in the provision of clean drinking water. A Geographic Information System (GIS) was used to map the spatial variability of different physicochemical parameters. A total of 59 analysed groundwater samples indicated that the ionic concentration was in the order of Na⁺ > Ca²⁺ > Mg²⁺ > K⁺ for major cations and HCO₃⁻ > SO₄²⁻ > Cl⁻ > NO₃⁻ > F⁻ > CO₃²⁻ for anions. Traces of arsenic and other toxic elements were found in the vicinity of the industrial zone, but they are well below the designated thresholds. The bivariate Gibbs diagram illustrates that 75–80% of samples fall in the rock-water interaction zone, and the rest of the samples lie in the rock-water interaction and evaporation processes. Piper’s plot revealed that seven samples were dominated by alkaline earth metals, seven samples showed the nature of alkalies, and the rest of the samples showed mixed character. Final water quality index (82) shows that the water quality is generally “good”, per the NSFWQI classification. This paper illustrates hydrochemical facies along with a natural mechanism controlling overall water chemistry.