Saturday, September 22, 2007

World Creating Food Bubble Economy Based on Unsustainable Use of Water


Lester R. Brown, EPI :: On March 16, 2003, some 10,000 participants [met] in Japan for the third World Water Forum to discuss the world water prospect. Although they [would] be officially focusing on water scarcity, they [would also] indirectly be focusing on food scarcity because 70 percent of the water we divert from rivers or pump from underground is used for irrigation.

As world water demand has tripled over the last half-century, it has exceeded the sustainable yield of aquifers in scores of countries, leading to falling water tables. In effect, governments are satisfying the growing demand for food by overpumping groundwater, a measure that virtually assures a drop in food production when the aquifer is depleted. Knowingly or not, governments are creating a "food bubble" economy.

As water use climbs, the world is incurring a vast water deficit, one that is largely invisible, historically recent, and growing fast. Because the impending water crunch typically takes the form of falling water tables, it is not visible. Falling water tables are often discovered only when wells go dry.

Once the growing demand for water rises above the sustainable yield of an aquifer, the gap between the two widens each year. The first year after the line is crossed, the water table falls very little, with the drop often being scarcely perceptible. Each year thereafter, however, the annual drop is larger than the year before.

[...] Aquifers are being depleted in scores of countries, including China, India, and the United States, which collectively account for half of the world grain harvest. Under the North China Plain, which produces more than half of China's wheat and a third of its corn, the annual drop in the water table has increased from an average of 1.5 meters a decade ago to up to 3 meters today. Overpumping has largely depleted the shallow aquifer, so the amount of water that can be pumped from it each year is restricted to the annual recharge from precipitation. This is forcing well drillers to go down to the region's deep aquifer, which, unfortunately, is not replenishable.

He Quincheng, head of the Geological Environmental Monitoring Institute in Beijing, notes that as the deep aquifer under the North China Plain is depleted, the region is losing its last water reserve—its only safety cushion. His concerns are mirrored in a World Bank report: "Anecdotal evidence suggest that deep wells [drilled] around Beijing now have to reach 1,000 meters [more than half a mile] to tap fresh water, adding dramatically to the cost of supply." In unusually strong language for the Bank, the report forecasts "catastrophic consequences for future generations" unless water use and supply can quickly be brought back into balance. [Complete Text]

MORE AT
Sentido.tv, Water Crisis Special Report
Sentido.tv, Sustainable Development Report
EPI, la Eco-Economía, en español

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