Since polluted water deteriorates the health of human beings and other animals, healthy society and environmental sustainability demand for clean and safe water. The presence of contaminants, and imbalance of common physicochemical parameters significantly disturb the quality of water. Taking the importance of clean and safe water into account, this study investigated fourteen physicochemical parameters of hand pump and open well water (main drinking water sources) from fifteen places of district Sudhnoti, Azad Jammu and Kashmir (AJK). The mean values of pH, electrical conductivity (EC), alkalinity, hardness and total dissolved solids (TDS) were 7.6, 349.9 μS/cm, 144, 152 and 190 mg/L, respectively. The mean concentration of Na+, K+, Ca2+, Mg2+, HCO3−, Cl−, SO42− and NO3− was found to be 9.5, 0.96, 9.9, 44.2, 144, 16.8, 8.1 and 6.67 mg/L, respectively. The turbidity as well as the concentration of CO32− was found below the detectable level in all water samples tested. Interestingly, all the studied physicochemical parameters had lower values than the maximum permissible level recommended by the world health organization (WHO) for drinking water. Eventually, the impacts of the studied physicochemical parameters, particularly anions and cation, on the efficiency of water treatment technology for real field application were discussed. The results revealed that physicochemical parameters of the groundwater of Sudhnoti, AJK had a slight effect on the degradation efficiency of one of the most widely used pesticides, lindane, in water by using ultraviolet–visible titanium oxide/hydrogen peroxide (UV–Vis)/TiO2/H2O2) and ultraviolet–visible/titanium oxide persulfate photocatalysis. Of note, the quality of hand pump and open well water which are the main drinking water sources of district Sudhnoti, AJK was found to be fit for drinking and other domestic purposes as well as for the ecosystem.