Correlation
In present study, an extensive investigation of physico-chemical parameters of water samples of river Ganga at Allahabad was carried out. For this, three sampling sites were selected along river Ganga at Allahabad depending upon their pollution index and usage viz: Phaphamau (S1), Daraganj Ghat (S2) and Sangam (S3). Five samples of water were collected during January 2014 to March 2014 at an interval of 15 days from these sites. The observed values of different physico-chemical parameters like pH, Temperature, Electrical conductivity (EC) , Turbidity, Total Hardness (TH), Chloride , Total Dissolved Solids (TDS), Total Alkalinity (TA), Dissolved Oxygen (DO) and Biochemical Oxygen Demand (BOD) of samples were compared with standard values recommended by world health organization (WHO). According to result obtained by analyzing various physico-chemical parameters of Ganga river in Allahabad city, maximum BOD was recorded at S1 and minimum at S3 whereas maximum DO was observed at S3 and minimum at S1. On the basis of our experimental result it was found that the values of turbidity, pH, BOD, TH, TA were highest at S1. Reason of high level of pollution at Phaphamau is attributed to the disposal of untreated sewage and industrial wastewater and cremation of dead bodies. Regular monitoring of River Ganga water quality is necessary to have a check on surface water pollution for the sake of healthy living of human. Correlation coefficients were calculated between different pairs of parameters to identify the highly correlated and interrelated water quality parameters.