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Water Resources of the USA



The USA is one of the first countries whose developing economy has met with a shortage of pure fresh water. Such conflicting situations have been caused by the exceptionally rapid growth of water consumption and by the constancy of the size of river runoff. The water crisis began to show at the beginning of the 60s. It was then when the gigantic projects were born to transport fresh water from Canada and Alaska to the main territory of the USA. At the end of 60s it became evident that the problem could not be solved by purifying utilized water.

By spending large sums of money on developing gigantic desalination plants it became clear that by channeling the runoff from the neighbouring territories and from the ocean an increase in the volume of polluted water would be brought about, which even at present overfills the rivers and lakes of the country.

It is the runoff which can be used without a full regulation of rivers by hydrotechnical installations. It is possible by recycling the same volume of water, which claims great requirements to the quality of their purification.

The main increase in water consumption takes place in that sphere of national economy, where water is necessary principally for cooling purposes – in industry, especially in heat-power engineering.

How can water losses be replenished? It is necessary to note the evergrowing consumption of ground water. The removal of considerably greater volumes of ground water that are taken at present will not diminish their total storage for a long time. Water supply at the expense of ground water is also convenient to satisfy the every day necessities of the population.

Other reserves that can be used are the water of the ocean. A wide substitution of fresh water for salt water for cooling purposes is assumed, mainly in heat-power engineering.

Over one quarter of the whole consumption of water will become possible due to the use of seawater. As concerning the abovementioned projects according to which fresh water is to be transported from Canada and Alaska and the entailed possibility to use the great reserves of hydropower of the western part of the continent, they have been cancelled.





Дата публикования: 2015-09-17; Прочитано: 472 | Нарушение авторского права страницы | Мы поможем в написании вашей работы!



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