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Staving off disaster on this scale would challenge even a richer nation. For Yemen, where 45 percent of the population survives on less than $2 a day, the odds are much worse.
Nearly 75 percent of Yemenis still live in the countryside, but an accelerating drift to the cities has overwhelmed urban utilities, including water. Sanaa has mushroomed to more than 2 million people from just 60,000 in the 1940s. "The deepest wells in Sanaa are now 1,000 metres -- you need an oil drilling rig to get that deep -- and water levels are dropping 6 to 12 to 20 metres a year," Scoble said. Yemen uses about 90 percent of its water to irrigate qat, a mild narcotic plant whose use dominates Yemeni society.
The area under qat cultivation is growing 10 to 15 percent a year, Iryani said, adding that efforts to make irrigation more efficient were hamstrung by a huge government fuel subsidy that masks the true cost of water, spurring qat farmers to pump more. "Farmers have no incentive to invest in modern irrigation techniques. Diesel is so cheap (at $0.17 a litre) they don't need to save water, and the return from qat is so high."
Iryani said the government could not enforce water drilling and irrigation laws on major consumers such as tribal chiefs, military officers and rich people even if it tried. He said 99 percent of water drilling is unlicensed. "Regarding water, we don't have the will or the means," he said. "The worst abusers of the system are the big shots, the people with power." He reckoned the government's best chance was to foster a social consensus on how to tackle the crisis.
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http://www.planetark.org/dailynewsstory.cfm/newsid/47293/story.htm