Multivariate Statistical Analysis of River Ganga Water at Rishikesh and Haridwar, India
Shivani Tyagi, Ramesh Chandra Dubey, R. Bhutiani, Faheem Ahamad
Abstract
Water quality parameters of Holy River Ganga was analyzed at two major sites, namely, Triveni Ghat (Rishikesh) and Har ki Pauri (Haridwar) situated at Uttarakhand (India) between March 2016 and February 2018 to find out the extent of pollution in the river by using water quality index (WQI). Values of most of the parameters, viz., turbidity (7.79 NTU), pH (7.24), total dissolved solids (217.46 mg/l), biochemical oxygen demand (2.10 mg/l) and total hardness (90.69 mg/l) were found higher in the rainy season. During the study, it was observed that as the holy River Ganga flows from Rishikesh to Haridwar, the values of certain parameters, such as pH (7.22), biochemical oxygen demand (2.58 mg/l), total dissolved solids (201.92 mg/l) and total hardness (107.13 mg/l) increase. Similarities and variations between the parameters were analyzed by a multivariate statistical method like principal component analysis (PCA), Pearson correlation coefficient, cluster analysis (CA), t-test, etc. Pearson correlation matrix of physicochemical parameters strongly correlates with each other indicating the inter-dependency of the variables. Seasonal similarity in summer and winter in dendrodram shows the impact of anthropogenic activity on the water quality of the Ganga River. The value of WQI indicates better water quality at Rishikesh (35.23) than that at Haridwar (47.34). The study concludes that water of the Ganga River at both sites can be used for domestic and agricultural purposes but precautions and extensive measures are necessary before consumption.