Global warming is also a cause for the water pollution directly by increasing the temperature of water, which results in the death of many aquatic animals and marine species.
Atmospheric deposition is also a cause for the water pollution directly affected by air pollution.
Atmospheric deposition is the process of polluting the water bodies by the presence of toxic substance present in polluted air. Polluted air includes the combination of gases like carbon dioxide, sulphur dioxide and nitrogen oxides, which later gets mixed up with a water vapors present in the air and form a toxic substance that falls to the ground in the form of acid rain. The toxins present in the acid rain get washed away into the water bodies, which contaminates the pure water and affects many aquatic animals and other marine species.
Leaking underground storage tanks
Leaking underground storage tanks is also a cause for the water pollution directly by polluting the pure water by leakages of fuels stored in metal tanks.
There are many underground metal and steel storage tanks, mainly constructed for storing highly flammable liquid products which are harmful to the surrounding environment such as petroleum and other fuels. These underground tanks may rust and begin to leak. These leakages of fuels may contaminate water and affect many aquatic animals and other marine species living in the water bodies.
Oil pollution is also a severe cause for the water pollution directly by polluting the pure water. As oil is insoluble in water and when it gets mixed with water it forms a thick sludge.
There are many ships and other tankers routinely moving in large oceans and seas. Oil pollution is caused by the oil spills from routine moving of oil tankers, ships, dumping and other accidents which takes place in or near by the water bodies. Oil pollution contaminates pure water and affects aquatic animals by causing suffocation and aquatic plants by blocking the entry of light for photosynthesis.
There was an accident on Ao Prao Beach at Samet Island in Rayong, a city in Thailand, which took place on 31st of July 2013. During this accident around 50,000 liters of crude oil was spilled into the sea from a pipeline unloading an oil tanker around 20 kilometers off the coast .The complete Ao Phrao Beach, which was famous for its white sand and clear water turned black oily mess.
Radioactive wastes are also referred as radio hazardous. They are the wastes containing radioactive chemical elements, which do not have a practical purpose. These wastes come from a number of sources, such as nuclear fuel cycle, nuclear weapon reprocessing industries, medical and other scientific processes. This includes wastes like naturally occurring radioactive metals, wastes emitted from nuclear fuel cycles, etc.
A radioactive waste is also a severe cause for the water pollution directly by polluting the pure water. Radioactive wastes typically comprises a number of radioisotopes, which have an unstable configuration of elements that decay by emitting ionizing radiations, which can be harmful to both human health and to the environment.
The wastes produced from the industries are a huge source of water pollution. These wastes are very harmful to both the human health and to the environment.
There are many industries, which uses fresh and pure water bodies for dumping all the waste away from the plant. The chemicals and other toxic pollutants emitted from the industries includes toxins like lead, mercury, sulphur, asbestos, nitrates and other chemicals that are very harmful and can lead to serious health hazards.
It is the practice of dumping of litter into the water bodies. They are very harmful and they not only result in water pollution but also harm many aquatic animals.
The marine dumping includes waste like cardboards, papers, plastic goods, glass, aluminum, rubber, etc. They take weeks and years together to decompose.
Sewage and waste water
Sewage and waste water are the pollutants released by many household, agricultural run-off, etc. These organic pollutants when discharged into fresh waters bodies increase the growth of algae which results in low oxygen levels and causes harm to the aquatic animals.
The rain water is a major source of sewage and waste water. The rain water washes away human excreta and animal dung, fertilizers, pesticides and other excrete into rivers, ponds and lakes and pollute the pure water bodies. Using this polluted water cause several water-borne diseases.