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14.The 20 million inhabitants of Mexico City and its surrounding area, for example, draw over 70% of their water from an aquifer that will run dry within 200 years, maybe sooner. Already the city is sinking as a result. In the Hai river basin in China, deep-groundwater tables have dropped by up to 90 meters.
15.Part of the beauty of the borehole is that it requires no elaborate apparatus. A single farmer may be able to sink his own tube well and start pumping. That is why India and China are now perforated with millions of irrigation wells, each drawing on the common resource. Sometimes this resource may be huge. But even big aquifers are not immune to the laws of physics. Many places are seriously overdrawn. In those places, farmers probably have to pay something for the right to draw groundwater. But almost nowhere will the price reflect scarcity, and often there is no charge at all and no one measures how much water is being taken.
16.Priced or not, water is certainly valued, and that value depends on the use to which it is harnessed. Water is used not just to grow food but to make every kind of product, from microchips to steel girders. The largest industrial purpose to which it is put is cooling in thermal power generation, but it is
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also used in drilling for and extracting oil, the making of petroleum products and ethanol, and the production of hydroelectricity. Some of the processes involved, such as hydro power generation, consume little water(after driving the turbines, most is returned to the river), but some, such as the techniques used to extract oil from sands, are big consumers.
17.Industrial use takes about 60% of water in rich countries and 10% in the rest. The difference in domestic use is much smaller, 11% and 8% respectively. Some of the variation is explained by capacious baths, power showers and flush lavatories in the rich world. All humans, however, need a basic minimum of two litres of water in food or drink each day, and for this there is no substitute. No one survived in the ruins of Port-au-Prince for more than a few days after January's earthquake unless they had access to some water-based food or drink. That is why many people in poor and arid countries—usually women or children—set off early each morning to trudge to the nearest well and return five or six hours later burdened with precious supplies. That is why many people believe water to be a human right, a necessity more basic than bread or a roof over the head.
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18.From this much follows. One consequence is a widespread belief that no one should have to pay for water. The Byzantine emperor Justinian declared in the 6th century that \law\all.\\deserves to drink.\
19.A second consequence is that water often has a sacred or mystical quality that is invested in deities like Gong Gong and Osiris and rivers like the Jordan and the Ganges. Throughout history, man's dependence on water has made him live near it or organize access to it. Water is in his body and in his soul. It has provided not just life and food but a means of transport, a way of keeping clean, a mechanism for removing sewage, a home for fish and other animals, a medium with which to skate and sail, a thing of beauty to provide inspiration, to gaze upon and to enjoy. No wonder a commodity with so many qualities, uses and associations has proved so difficult to organize.
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现代大学英语精读4第二版Unit 5A For Want of a Drink 课文原文
