Despite various government efforts, the scale of the water pollution in India is still very high.

Water pollution or the contamination of water bodies (lakes, rivers, oceans, aquifers and groundwater), occurs when pollutants are directly or indirectly discharged into water bodies without adequate treatment to remove harmful compounds.

Water pollution affects plants and organisms living in these bodies of water. In almost all cases, the effect is damaging not only to individual species and populations, but also to the natural biological communities.

A Child Health and Nutrition Research Initiative (CHNRI) report states that am estimated of 580 people in India die of water pollution related illness every day.

The largest source of water pollution in India is untreated sewerage. Other sources of pollution include agricultural runoff and unregulated small scale industry. Most rivers, lakes and surface water in India are polluted.

A 2007 study finds that discharge of untreated sewage is the single most important cause for pollution of surface and ground water in India. There is a large gap between generation and treatment of domestic waste water in India. The problem is not only that India lacks sufficient treatment capacity but also that the sewage treatment plants that exist do not operate and are not maintained.

Rivers Yamuna, Ganga, Gomti, Ghaggar, Chambal, Mahi, Vardha are amongst the other most coliform polluted water bodies in India.

India has made progress in the supply of safe water to its people, but gross disparity in coverage exists across the country. Although access to drinking water has improved, the World Bank estimates that 21% of communicable diseases in India are related to unsafe water.