Sewage drains are the main sources to transport domestic, agricultural, sewer, slaughter houses, industrial pollutants, etc. Rivers are being polluted through various agencies mainly by municipal sewage, effluents from automobile service stations, discharge from cottage industries, bathing and washing of clothes etc. To study the impact of sewage water on the chemistry of rivers in an industrial city, Ludhiana; estimation of physico-chemical characteristics was done on the most polluted drain that carries a major amount of domestic and industrial run-off towards the rivers. Standard methodologies adopted for the analysis indicate that the sewage discharged into the river increases its pH, acidity, alkalinity, B.O.D, C.O.D, chloride, nitrate, phosphate and content of heavy metals like iron, and zinc. With domestic wastes, several nutrients also come into the river. These nutrients play an important role in aquatic eco-system.