Hydrogeochemical and geospatial analysis of water quality for domestic and irrigation purposes in Padmanabhapuram, Kanyakumari District, India

Water is an essential resource and is a basic need for all living beings. A combination of natural and human factors impacts the consistency of water. In compliance with international norms in Padmanabhapuram, District of Kanyakumari, this analysis is projected to study the water suitability for household and irrigation determinations. Eighteen sampling locations with Global Positioning System were surveyed with coordinates. Water quality index (WQI) was developed for evaluating the suitability of water for drinking and irrigation. The results showed that twelve sampling locations are suitable for drinking. The spatial interpolation approach was employed to provide the distribution map of drinking water quality. The integrated map shows that 883,417m2 (46.03%) and 950,704m2 (49.54%) of area fall under the poor and very poor quality of water, respectively. For drinking purpose, the area of 2725 m2 (0.14%) and 7659 m2 (0.4%) was covered in excellent and good grade in water quality, respectively. The remaining 74,336 m2 (3.87%) of the study area is unsuitable for consumption. Total dissolved solids (TDS), electrical conductivity (EC), sodium adsorption ratio, magnesium hazard, permissible index, residual sodium carbonate (RSC), Kelly’s ratio, % sodium, soluble sodium ratio and geographically distribution maps are prepared to determine the irrigation suitability. TDS and EC are more than the permissible limit at sampling stations (S14, S15 and S16) whereas more RSC values at S8. The Piper trilinear diagram and Durov’s diagram of the hydrogeochemistry analysis show the most significance in the parameter of Ca and Cl whereas less significance in Na and K. In the statistical analysis, TDS and EC are highly correlated with TA, Ca, Na and Cl while less correlated with BOD and COD.