Shailaja Mali, Kiran A. Thabaj and Purandara K. Bekal
Abstract
To measure the quality of groundwater of Ghataprabha sub basin for domestic and irrigational uses, thirty eight groundwater samples were collected during pre-monsoon (PRM) and post-monsoon (POM) during the year 2017 from Ghataprabha sub basin, samples were tested for various physico- chemical factors such as pH, TDS, EC, Ca2+, Mg2+, Na+, K+ (cations) and SO4-2, HCO3-2, F-, PO43- and NO3- (anions). Spatial variation maps for cations viz Na+, K+, Ca2+, Mg2+, and anions like bicarbonate, sulphate, nitrate, phosphate, and fluoride, were generated. Principal Component Analysis (PCA) of groundwater quality data was conducted for both PRM and POM. During pre-monsoon three components contributed with 84.22% variance, PC1 contributed 49%, PC2 and PC3 contributed 23% and 12 % respectively and during post monsoon four components contributed total per-cent variance of 84.9%. PC1 contributed 45%, PC2 contributed 20%, PC3 contributed 10% and PC4 contributed 8% respectively. Further Piper method was applied to classify the water type. Wilcox diagrams and USSL classification were also done to check the suitability of water for irrigation and 90% water samples were found to be suitable.