Kayathri Untreated Sewage Once Water example essay topic

Christine How is water polluted Water is polluted when any harmful substance is released into the water thus contaminating or making it unsuitable for marine life to survive. The main water pollutants are: 1) Factory Waste 5) Farm Waste 2) Fertilisers 6) Oil 3) Pesticides 7) Litter 4) Untreated Sewage Take a look at a picture of a polluted river in Sao Caetano do Sul in Sao Paulo, Brazil. Dilip Factory Waste Factory waste is made out of a wide range of of impurities including posoinous substances such as mecury, cynide and lead; and corrosive, acidic or alkaline solutions. Toxic wastes when discharged into rivers and seas pollutes and poison aquatic life which in turn will harm people who consume food taken from this water. Kayathri Fertilizers Chemical fertilisers provide aquatic life with nourishment. This upsets the eco-system in the water, causing algae to grow in large quantity.

The algae prevents sunlight from entering the water. This suffocates and kills aquatic life by using most of the dissolved oxygen in the water. Christine Pesticides and Farm waste Pesticides are chemicals sprayed onto crops to kill pests. However the pesticides can be washed down by the rain, posoining life in the water ways. In fish farms, chemicals are added to the water to prevent fish diseases. The chemicals, uneaten fish food and fish excrement are finally washed off into streams and rivers, polluting the water.

Animal waste from farms also pollute the water when they are washed off into rivers and streams. Dilip Oil and Litter Oil does not dissolve in water yet it can cause enormous damage to marine life. Sea vessels are mainly responsible for causing oil spills. Oil prevents oxygen in th air from dissolving in the water this deprives aquatic life of oxygen.

Marine life are also posoined and killed by the oil. Every year thousands of marine animals drown or are wounded when they get entangled in fishing nets and litter packaging. Kayathri Untreated sewage Once water has been used, it becomes sewage. Sewage contains harmful substances and germs.

Sometimes, untreated sewage is discharged into open drains or rivers causing diseases such as cholera, gastric flu and typhoid. Coliform bacteria found in untreated sewage cause stomache upsets if they enter our body. If raw sewageis discharged into a river bacteria will develop. Raw sewage also contains phosphates from detergents.

Water with detergent will dissolve less oxygen. Oil prevents oxygen in the air from dissolving in the water this deprives aquatic life of oxygen.

Bibliography

Encarta 2000 J Spencer.