In a developing country like India, there are many sources of water pollution. For e.g.● Household detergents flow directly into the river.● Sewage in most of the urban areas are untreated and directly led to rivers.● Effluents from industries is usually discharged into nearby water bodies.● All the above courses harmful chemicals and pathtogens to enter into human body and cause various diseases.● Oil spills from oil tankers or refineries etc. kills a lot of aquatic birds & fishes.● Thermal pollution from thermal power plants is also a major concern as it causes warming of water that kills aquatic plants & fishes.