Hydrochemistry for the assessment of groundwater quality in the Kathua region, Jammu and Kashmir, India

Groundwater is a vital natural resource in the Kathua region of the Union Territory of Jammu and Kashmir, Northern India, where it is used for domestic, irrigation, and industrial purposes. The main purpose of this study was to assess the hydrochemistry of the groundwater and to determine its suitability for drinking, irrigation, and industrial uses in the Kathua region. In this study, 75 groundwater samples were collected and analyzed for the physicochemical parameters such as electrical conductivity (EC), total dissolved solids , pH, and various cations and anions. The analyzed data were computed for designing groundwater quality index to know the suitability for drinking purposes. The EC, sodium percentage, permeability index, and magnesium hazard were assessed to evaluate groundwater suitability for irrigation. Further, the corrosivity ratio was assessed to find the groundwater quality criteria for industrial purposes. The comprehensive results obtained from the water quality index indicate that almost all groundwater samples are suitable for drinking. The ionic abundance is in the order of Ca²⁺ > Na⁺ > Mg²⁺ > K⁺ for cations, and HCO₃⁻ > SO₄²⁻ > Cl⁻ > NO₃⁻ for anions, respectively. The Piper diagram shows that hydrochemistry of the groundwater is dominated by alkaline earth metals (Ca²⁺, Mg²⁺) and weak acids (HCO₃⁻). According to the Gibbs diagram, the chemistry of groundwater is mainly controlled by the rock–water interaction process, indicating that most of the groundwater samples of the area are of bicarbonate type. The EC results classify the groundwater as excellent to good; the sodium percentage also indicates that the water is fit for irrigation. According to the Wilcox and USSLS diagrams, and permeability index, a majority of samples are suitable for irrigation with a few exceptions. The magnesium hazard depicts that there are few samples (19%), which are unsuitable for irrigation. According to the corrosivity ratio, 65 samples are safe for industrial use while the remaining 10 samples are considered to be unsafe. Thus, it is found that most of the groundwater in the area can be used for drinking, irrigation, and industrial purposes.