Groundwater quality in Eastern Karnataka, India – an end-use analysis
- pp14-33
Physico-chemical characteristics of groundwater in parts of Eastern Karnataka are examined to determine whether they conform to the quality standards of water used for drinking, agriculture and industrial end uses. Eighty eight samples from forty five villages have been analysed for this purpose. Cation abundances in the groundwater are in the order: Na+ > Ca++ > Mg++ > K +. Anion abundances are in the order HCO− 3 > Cl− > SO2 4 > NO− 3 > F −. Only in one locality, SO2 4 content is very high. According to Piper’s classification, 42% of the water samples belong to Ca–Mg–Cl type; 30% to the Ca–Mg–HCO3, 16% to Ca–Na–HCO3, 9% to NaCl and 3% to NaHCO3 types. Gibbs plot shows that water–rock interaction is the dominant process controlling the major ion chemistry, although there is evidence of evaporation at some places. Out of 45 villages, excess of fluoride, nitrate and uranium are found in 23, 28 and 26 villages respectively. Phosphate is higher than 1 mg/l in all the villages. Lithium exceeds the permissible limit in 27 out of 43 localities. Concentrations of other trace elements Ag, Al, Ba, Tl, As, B, Co, Cr, Cu, Fe, Li, Mn, Ni, Pb, Se, V, Zn and U were determined in selected samples. Arsenic exceeds the permissible limit for drinking water in one village. Groundwater in 21 out of 45 villages is suitable for agriculture, while
Agriculture drinking end-use geochemistry industry groundwater