Application of Chemometric Techniques in the Assessment of Groundwater Quality of Udham Singh Nagar, Uttarakhand, India

Abstract

In the present study, groundwater quality of district Udham Singh Nagar was evaluated using chemometric techniques viz. cluster, principal component and factor analyses to investigate the spatial variations of the most significant water quality parameters and to determine origin of pollution sources. Water samples collected from 6 sampling sites were analysed for 23 water quality parameters in pre- and post-monsoon seasons during the years 2010 and 2011. The concentration of alkalinity, total hardness, total dissolved solids, calcium, magnesium total coliform and faecal coliform of samples exceeded the Bureau of Indian Standard limits. Correlations among selected water quality parameters were statistically examined. Cluster analysis grouped 6 sampling sites into three clusters, i.e. less, moderate and high polluted, based on similarities of water quality characteristics. The principal component/factor analysis extracted four factors, which explain the ground water quality. Factor 1 (anthropogenic pollution) includes hardness, alkalinity, TDS calcium and magnesium, Factor 2 (hydrogeologic and agricultural pollution) includes turbidity, pH and nitrate, Factor 3 (industrial pollution) comprises \(\hbox {Cl}^{-}\) and Fe, and Factor 4 (agricultural pollution) includes sulphate. Piper diagram illustrated that water samples of the studied area are dominant of \(\mathrm{{Ca}}{-}\mathrm{{Mg}}{-}\mathrm{{HCO}}_{3}\) hydrochemical facies. Moreover, water quality index (WQI) described the suitability of water sources for drinking purpose. Compared to 2010, WQI was higher in 2011, which led most of the sites unsuitable with grade ‘E’. The results revealed that the selected groundwater samples, being used for drinking and domestic purposes, are deteriorating, and thus highlighted the application of proper treatment strategy before domestic water supply.