25% pollution is caused by the industries and is more harmful. Waste from the industries like, sugar, textile, electroplating, pesticides, pulp and paper are polluting the water. Hazardous material discharged from the industries is responsible for surface water and ground water contamination. Contaminant depends upon the nature of industries. Toxic metals enter in to water and reduced the quality of water .Polluted river have intolerable smell and contains less flora and fauna. Large amount of domestic sewage is drained in to river and most of the sewage is untreated.
Increasing population is creating many issues but it also plays negative role in polluting the water. Increasing population leads to increase in solid waste generation. Solid and liquid waste is discharged into rivers. Water is also contaminated by human excreta. In contaminated water, a large number of bacteria are also found which is harmful for human health. Urbanization can cause many infectious diseases. Overcrowding, unhygienic conditions, unsafe drinking water are major health issues in urban areas. Pesticides are used to kill bacteria, pest and different germs. Chemical containing pesticides are directly polluting the water and affect the quality of water which leads to eutrophication.