Abstract
Bhavani is one of the important rivers in Tamil Nadu. Many industries, particularly textile processing units, tanneries, sugar factories and distillery units, are situated on the banks of Bhavani river. These industries let out untreated and partially treated effluents into the river stream. It is, therefore, decided to study the quality of water and to estimate its pollutional load in the River Bhavani. Samples of water were collected at selected points and physcio-chemical and biological examinations were carried out. A simple, comprehensive water quality index system, devised by NSF of USA and an alternative method adopted, were applied and the water quality assessed at every point. It was observed that at the start of monsoon season the water quality in the Bhavani river was good, but showed a progressive decline from its origin to further distances as it passes through human settlements and industrial areas.