Seasonal variation in bacterial population and their correlation with physico‐chemical factors in the riverine system

Significant positive correlation between physico‐chemical factors and different bacterial populations were studied. Higher values of heterotrophic bacteria (HT), total coliform (TC), faecal coliform (FC) or faecal streptococci (FS) and the occurrence of E. coll, Streptococcus faecalis, Clostridium welchii ( C. perfringens), Aerobactor aerogens and A. cloacae at downstream point (Station II) indicated the degree of sewage and human waste pollution in the riverine system. The concentration of TC and FS at Station II was more than the prescribed permissible limits of ISI and WHO. Hence, the results show that river water has been deteriorating considerably due to high pollutional load and may pose a great risk to human health if consumed directly from the source.