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The situation has been exacerbated by what seemed like a great idea at the time to meet India's burgeoning water needs -- drilling deep into the earth to get to supplies far below the ground. The programme, begun in the 1960s, was at first a great success and revolutionised access to water in the hard rock areas which make up four-fifths of India's landmass, bringing supplies to millions of households.
But the success also bred abuse as high-speed drilling technology, spurred by free power to farmers given by vote-hungry politicians, was used for irrigation for crops needed to feed India's ever-growing population and a focus on water-thirsty cash crops. "The emphasis on mass irrigation set India on the path of unsustainable water resources management," says Black.
Now some 70 percent of India's irrigation water and 80 percent of its domestic water supplies come from groundwater rather than from surface water, according to the World Bank. In a report late last year, the Bank said that India has no proper water management system, its groundwater is disappearing and river bodies are turning into sewers. "Estimates reveal that by 2020, India's demand for water will exceed supply," it said. The Centre for Science and Environment said in parts of New Delhi the groundwater level was dropping by 10 meters (33 feet) each year.
"The monsoon not only fills rivers and streams but as rainfall seeps into the soil it recharges the underground aquifers," says Black. But "the exploitation of the resource has taken place at a speed which does not allow time for the water table to recoup its losses". Where once a depth of 10 metres (33 feet) was enough for a plentiful supply, a depth of 80 to 100 metres may now be needed. In many areas the uptake of groundwater has crossed the limit imposed by natural rates of renewal. "In many parts of the country, it (the water problem) is now irreversible," says Rupert Talbot, a water consultant with the United Nations Children's Fund (UNICEF). "You can go to parts where they are drilling so deep that they are mining fossil water that is 20,000 years old. It will never be recharged (by rains)."
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http://www.terradaily.com/reports/Water_Crisis_Looms_In_India_As_Drilling_Depletes_Resources.html