Water Pollution

                                    Water pollution is any contamination of water with chemicals or other foreign substances that   detrimental to human, plant or animal health. These  pollutants  include  fertilizers  and pesticides  from  agricultural  runoff ,sewage  and  food processing waste lead, mercury and other  heavy metals ,chemical  wastes  from industrial  discharges  and   chemical  contamination  from hazardous  waste sites. Worldwide nearly two billion people drink contaminated water that could be harmful to their health.

        Water has many remarkable properties. It  is sometimes  referred to as ‘ the  universal  solvent ‘,readily   dissolving  a wide range  of  chemical substances .It also  acts  as a  fluid  medium  facilitating  the  dispersal  of  un-dissolved  particulate matter .

 

    Sources of Water Pollution 

1.    Domestic Waste and Sewage :

                 Raw sewage  contaminates  water with pathogens .Micro-organisms  causing degradation of  sewage take up most of  the oxygen present  dissolved in water .Organic  waste gives rise to  scum and sludge that makes  the water  unfit  for recreational and industrial use .It induces the growth  of some algal blooms that add to the  depletion  of oxygen , addition of more  organic matter and fouling of water .Modern day  detergents  degrade very slowly . They fore accumulate and render the water unfit for human and animal use. The phosphates present in detergents further stimulate algal growth that adds to the organic loading of water.

 

 

2.    Surface Run –Off :

           The pollutants present on the surface of land and fertilizers added to the soil are washed down in to water reservoirs and water courses during rain. This flow of fertilizer rich water in to streams and lakes gives rise to eutrophication.

3.    Marine Pollution :

                            Ocean pollution is caused by ship –generated discharges of soil and petroleum products, noxious liquids, packaged dangerous goods, sewage, garbage etc. Migrating birds caught the oil slicks losing their power of flight due to closer interlocking of barbules of the feathers, is common enough.

      Eutrophication: Any lake or sheet of fresh water, to begin with is oligotrophic, supporting a minimum of life forms .Therefore its productivity would be minimal .But in times it comes to be occupied by immigrant life forms, which on death and decay would make further immigration possible. The lake is then said to have reached a mesotrophic level .Finally it comes comes to be occupied by a rich flora and fauna when it is said to have reached the eutrophic level i.e. When its productivity had reached its maximum. In nature, this would take place through thousands of years but with industrialization  and other forms of human activity ,this process of eutrophication as it is called is achieved in to a few decades.   

 

Degree of Water Impurity:

                    Water pollution by organic wastes is measured in terms of Bio-chemical Oxygen Demand (BOD).BOD is defined as the amount of Oxygen required in milligrams for five days to metabolize waste present in one liter of the water at 20°C .Since BOD is limited to organic wastes it is not a reliable method of measuring water pollution. It measures all Oxygen consuming pollutant materials present in the water.

                     Chemical Oxygen Demand (COD) .It is an indicator of water or effluent quality which measures oxygen demand by chemical means using potassium dichromate as the oxidizing agent .Oxidation takes 2hours and the method is thus much quicker than a 5-day BOD assessment. The BOD: COD ratio is fairly constant for a given effluent.

 

Control of Water Pollution

            Water Pollution can be controlled to a large extent on the principle, ’the solution to pollution is dilution.’’

           The various methods for the control of water pollution are

v The sewage pollutants are subject to chemical treatment to change them in to non-toxic substance or make them less toxic.

v Water pollution due to organic insecticides can be reduced by the use of very specific and less stable chemicals in the manufacture of insecticides.

v Oxidation ponds can be useful in removing low level of radioactive waste.

v Thermal pollution can be reduced by employing techniques through cooling, cooling ponds, evaporative or wet cooling towers and dry cooling towers. The purpose is that the waste in the rivers and streams should not get hot

                               Sources and causes

 

v Industrial activities: The industries all over the world that brought prosperity and affluence, made inroads in the biosphere and disturbed the ecological balances.

v Vehicles: The smoke emitted by vehicles using petrol and diesel and cooking coal also pollutes the environment .The multiplication of vehicles, emitting black smoke that, being free and unfettered, spreads out and mixes with the air we breathe. The harmful smoke of these vehicles causes air pollution. Further, the sounds produced by these vehicles produce causes noise –pollution.

v Rapid urbanization and industrialization: The urbanization and the rapid growth of industrialization are causing through environmental pollution the greatest harm to the plant life, which in turn causing harm to the animal kingdom and the human lives.

v Population overgrowth: Due to the increase in population, particularly in developing countries, there has been surge in demand for basic food, occupation and shelter.

                         

         Environment pollution has negatively affected the life of both human beings and animals .Almost all of our gains in the fields of industrial progress, science and technology had so far been realized at the cost of our health .All this really leaves us wondering if all our achievements and industrial civilization really help us climb the peaks of prosperity or simply take us down the blind alleys of adversity. The environmental pollution is not caused by the fall –out from nuclear tests or industries alone. The smoke left behind the automobiles and other vehicular traffic, the increasing use of synthetic detergents, nitrogen fertilizers and insecticides contaminate both air and water.

v The water we drink the vegetables are all contaminated today. As a result of this contamination our world is afflicted with a quite a number of incurable diseases.

v Nothing in this world is immune, no life is safe and the future of this world is bleak.

v The factories are mostly built in populated areas and the smoke emitting vehicles play through the congested areas.

v Air pollution may causes severe lungs-diseases,asthma,brain disorder diseases,etc.

v Soil pollution may have negative effect on farm output ratio. It can also contaminate the ground water. 

v The heat generated by industries and vehicles causes thermal pollution by raisin the environmental temperature of the nearby areas.

          The birth of mills and factories is the result of the growth of industry in this machine –predominated age. As long as they will be there, they must emit smoke, pollute the air and hasten our end by slow poisoning. The worst industrial environment tragedy occurred at Bhopal on December 3, 1984 as a result of toxic and poisonous leakage of methyl isocyanate (MIC) gas from a multi-national Union Carbide pesticides  manufacturing plant .Over 2000 people      including woman and children were killed, and hundreds were severely hurt.                                                    

Solution

What then is the remedy?

             There surely cannot be any radical solution, for the existing factories cannot be bodily lifted to a place far from the populated zone .However, the following attempts can be made to solve the problem of environmental pollution.

v The Government can at least see that future factories are set up at a distant place, an industrial complex far away from the township.

v Researcher may find out how to avoid harmful smoke from running vehicles.

v Deforestation should be stopped and Forestry should be developed.

v Discharge of factory waste in rivers should be banned so as to make the river water free from pollution.

Initiatives

v The UN Conference on Human Environment was convened to study the profound changes in the relationship between man and his environment in the wake of modern scientific and technological developments.

v  The World Health Organization also set up an international network for the monitoring and study of air pollution on a global scale and for devising possible remedies.

Conclusion

                       We can very well notice the abnormal behavior of the seasons – the cycle developing clogs in its wheels; and worried experts fear that the disturbed balance in the biosphere has assumed such a serious proportion that very soon our world would be uninhabitable like Hiroshima of 1945.If we fail to restore the ecological balance right now, it would be too late tomorrow.