Water quality of the Ganga River - An overview

The Ganga is not only a holy river, but also a lifeline of a large population of India, as it covers more than 26% of the country's area in its basin in the north and drains 25% of the annual run-off. Fast urbanization, industrialization and steep demand for water have led to serious problems of water quality degradation. Water quality monitoring indicated that the river is polluted in some of the segments, the worst affected lying between Kannauj and Allahabad, approximately 350 km long. About 12,222 million litres per day (mld) of domestic and 2500 mld of industrial wastewater is generated in the entire basin, out of which about 2573 mld of wastewater is generated along its bank. Many of its tributaries are heavily polluted and the main water quality issues are, organic pollution indicated by BOD and pathogens indicated by coliform count. There is a fluctuating trend of water quality attributed to the flow conditions in the river which depend on rainfall and water abstraction. In view of water scarcity in the basin, it is very important that no wastewater be discharged into the river. There is an urgent need to augment water availability in the basin by rainwater collection, water conservation and environmental flow determination in various segments of the river affected by water abstraction.