Pollution can affect rain, rivers, lakes, oceans and groundwater. Both natural processes and human activity can cause water pollution. Both surface water and groundwater can be polluted with minerals leached from the soil, acids from decaying animal products. Pollutants can come from agricultural, urban and industrial sources, as well from untreated human wastes. Polluted water may look clean, but it contains germs, chemicals or other materials that can be harmful and cause illness or even death.
Industrial wasters is the primary cause of water pollution in the United States.
Industries dump three to four times as many pollutants into wastewater as do all of the country's sewage systems connected. This wastewater contains many toxic chemicals. Much of this waste is released directly into the water. Acid rain is another result of industrial processes that involved the burning of coal, oil and other fuels. The second cause of water pollution in the United States is Sewage waste.