A Study on Physicochemical and Bacteriological Properties of Drinking Water in and around Dhaligaon Area of Chirang District of Assam

Dhaligaon is a well known site in the industrial map of India. Indian Oil Corporation (Bongaigaon Refinery), one of the few refineries of India is situated here along with a large number of industries of medium and small grades. Ten samples of drinking water comprising of ring wells, tube wells, tara pumps and deep tube wells of in and around Dhaligaon area were analyzed by standard methods for three seasons namely, Monsoon, Post Monsoon and Pre Monsoon from June 2008 to May 2009. The P^H values all the water samples were found to be below the desired limit (6.5-8.5). Sixty percent of the samples crossed the permissible limits of both turbidity and iron. One sample crossed the permissible limit of lead while another touched the permissible limit. The other physico-chemical properties of the water samples were found to be bellow the respective permissible limits. Eighty percent and fifty percent of the samples indicated the presence Coliform and E. coli respectively in the drinking water. The study reveals that drinking water of the area must be properly treated before its use.