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Pollution of Water

Water Pollution occurs due to contamination of water by humans. The causes of water pollution include dumping of commercial and local waste in water bodies.

According to the World Health Organization (WHO), contaminated water is water whose constitution has been altered to the point that it is no longer useful. We can also say that In other words, it is hazardous water that must not be consumed or utilised for agriculture, and it also causes diseases such as diarrhoea, cholera, and, typhoid, and poliomyelitis, which prove fatal for lakhs every year. Industrial waste, plastic waste, household waste, and community waste are the major contaminants that pollute our water bodies. These pollutants may or may not be visible through the naked eye. We can prevent water pollution by treating the waste, opting for reuse and recycling of water, and opting for sustainable and environment-friendly agricultural practises.

Water pollution

  • Water pollution is defined as the discharge of pollutants into deep underground water or either into ponds, streams, rivers, and seas. The pollution reaches a level such that the contaminants interfere with healthy water usage or the normal ecological processes.
  • The pollution of water mainly happens when both solid and liquid contaminants mix with water bodies, starting from streams to oceans. 
  • Sewage water, hot water, agricultural run-offs, oil spills, industrial wastes, and plastics are some of the main reasons for water pollution. 
  • The release of hot water and radioactive waste into rivers and other water bodies is also a form of water pollution.

Causes of water pollution

  • Disposing sewage, solid wastes, ashes, flowers, and so on causes water contamination.
  • People bathe, wash clothes, throw away household garbage, idols, and so on.
  • Industrial wastes from oil refineries, thermal power plants, chemical factors, and others also cause pollution of water. 
  • Agricultural run-offs including pesticides, fertilisers, and insecticides pollute the rivers and lakes.
  • Thousands of plastics are deposited into the water every month causing pollution.
  • Oil spills from onshore drilling sites and oil vessels have become one of the prime causes of water pollution.
  • The addition of fertilisers to the water causes algal bloom- uncontrolled growth of algae that further reduces dissolved oxygen content, causing oxygen debt.
  • Heavy metals like mercury, arsenic, and others also cause water pollution.

Case study- The Ganges River

  • According to the recent WWF study, it was revealed that the Ganges is one of the most polluted rivers in the world.
  • Several places are suffering from extinct aquatic life, and these areas are known as the “dead river zone”. 
  • Kanpur is one of the leading waste producers that causes river pollution like chemicals, leather cleaners, ashes, and so on. 
  • In 1985, the plan named the Ganga Action Plan was initiated for water purification. 
  • Another initiative has been undertaken in 2016- the National Mission for Clean Ganga.

Potable water and water purification

After water purification, the result is often termed potable water that is fit for drinking purposes. There are several methods by which water can be purified and all the impurities can be removed like: 

  • Using a physical filter will block the solid impurities from water.
  • Boiling the water will kill the germs as well as dissolve some chemical precipitates.
  • Chlorination is another way by which chlorine is added to water for removing germs and microbes.

Measures to prevent water pollution

  • Industries should be advised to take proper measures to prevent water pollution. This will include treating the discharge before releasing it into the water bodies. 
  • Reducing, recycling, and reusing the solid wastes, especially plastics, water bottles, bags, and others for minimising the solid waste. 
  • Using the potable water carefully and preventing wastage. 

Conclusion

Water pollution is defined as the adulteration of water by materials that are hazardous to humans. Water pollutants include sewage, chemical pesticides, and industrial effluents. Potable water is water that is pure and safe to drink. Water is a valuable natural resource. We need to learn how to preserve it. The river Ganges is one of the most polluted rivers in the world. To clean this river and prevent further pollution, the Ganga Action Plan was initiated. Individuals, communities, and industries must all work together to prevent water pollution. Treatment of industrial waste before disposing in water bodies can effectively reduce water pollution.