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"Conquering hunger and coping with an estimated 3 billion extra people by 2050 will result in an 80 percent increase in water use for agriculture on rainfed and irrigated lands," it added. Demand for irrigation -- which absorbs about 74 percent of all water used by people against 18 percent for hydropower and other industrial uses and just 8 percent for households -- was likely to surge by 2050.
Many nations are also shifting to produce biofuels -- from sugarcane, corn or wood -- as a less polluting alternative to fossil fuels. Oil prices at $75 a barrel and worries about global warming are driving the shift.
"If people are growing biofuels and food it will put another new stress. This leads us to a picture of a lot more water use," David Molden, who led the study at the Sri Lanka-based IWMI, told Reuters.
Still, the report said that "the world is not 'running out' of water", concluding that there was enough land, water and human capacity to solve the shortages.
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http://today.reuters.co.uk/news/articlenews.aspx?type=topNews&storyID=2006-08-21T000552Z_01_L18850725_RTRUKOC_0_UK-ENVIRONMENT-WATER.xml