"World on Edge details the vice closing around us: a quadruple squeeze of global warming and shortages in food, water and energy. Then it explains the path out—and how little time we have left to take that path. Got anything more important to read than that?" —Peter Goldmark, former head of the Port authority of New York and New Jersey, President of the Rockefeller Foundation, and CEO of the International Herald Tribune
Although public attention has recently focused on the depletion of oil resources, the depletion of underground water resources poses a far greater threat to our future. While there are substitutes for oil, there are none for water. Indeed, we lived for millions of years without oil, but we would live for only a matter of days without water.
Not only are there no substitutes for water, but we need vast amounts of it to produce food. At the personal level, we drink roughly four liters of water a day (nearly four quarts), either directly or indirectly in various beverages. But it takes 2,000 liters of water—500 times as much—to produce the food we consume each day.
Since food is such an extraordinarily water-intensive product, it comes as no surprise that 70 percent of world water use is for irrigation. Although it is now widely accepted that the world is facing water shortages, most people have not yet connected the dots to see that a future of water shortages will also be a future of food shortages.
Excerpted from Chapter 6, “Stabilizing Water Tables,” in Lester R. Brown, Outgrowing the Earth: The Food Security Challenge in and Age of Falling Water Tables and Rising Temperatures (New York: W.W. Norton & Company, 2005), available for free downloading and purchase at www.earth-policy.org/books/out.