Abstract

This study examined the concentrations of Escherichia coli in soil and water samples, and some physicochemical properties of water collected from the Karnafuly River estuary, Bangladesh during March-June 2012. Among the water parameters, temperature was in the range 26.5  to 32°C, salinity varied between 0 and 5 ppt, pH values ranged from 7.5 to 7.9 and dissolved oxygen (DO) was recorded at concentrations of 2.28 to 2.91 mg/l. The average total E. coli were 26 cells/ml in water, but the sediment contained 96.42 cells/g of E. coli. The population of E. coli was always higher in sediment than those that occurred in water among all sampling stations. The growth of E. coli were positively correlated (P < 0.01) with water temperature and negatively correlated with salinity, pH and DO. The data on water quality parameters and occurrence of E. coli indicated that water of the Karnafuly estuary is polluted and unhygienic for drinking, even impossible to use for washing purposes without any treatment.

Key words: Karnafuly, Escherichia coli, physicochemical, estuary.