Determination of water quality index for the evaluation of surface water quality for drinking purpose

Water quality was determined at four sites at a stretch of 5 Km of the river Ganga in Haridwar city (Site 1st Harkipauri, Site 2nd Birla ghat, Site 3rd s Mayapur and Site 4th Singhdwar) for a period of 1 year (January 2009 to December 2009). Relatively low values of turbidity, COD, total alkalinity and total hardness were recorded at Site 1 and Site 3 and site 4 as compared to Site 2. On the basis of water quality standards given by Central Pollution Control Board, the water quality at all the four sites was found to be in category A-C. The mean values of these parameters were compared with WHO and ISI standards. For computation of water quality rating and water quality index, thirteen parameters were considered. The water quality index at stations Site1, Site 2, Site 3 and Site 4 was 64.80, 57.29, 59.09 and 59.22 respectively