An investigation was conducted near the industrial areas of West Bengal, Indian subtropics to study the effect of emissions through various factories and thermal power plants on the quality of water in lakes, tanks, ponds, even well waters in relation to its use in the welfare of the society (agricultural use, psciculture and other domestic uses). The results showed that intensity of acidity (water pH) as well as concentration of various soluble salts and BOD and COD in the vicinity of an industrial area (i.e. within 100 metres) were very low. A substantially higher acidity and ion concentration were recorded up to 1 km away from industry, where the growth of aquatic plants, organisms and the production of fish (in lakes and tanks) were severely affected. The results further indicated that the acidity of water gradually increases up to pH 5.4 and concentration of sulphates and chlorides (880 and 570 mg 1−1 respectively) between 1–2 km from the industriy, suggesting that aquatic ecosystems and domestic, agricultural and fish production are less affected with increasing distance from industry.