Peak Water: Aquifers and Rivers Are Running Dry
That the news is familiar makes it no less alarming: 1.1 billion people, about one-sixth of the world's population, lack access to safe drinking water. Aquifers under Beijing, Delhi, Bangkok, and dozens of other rapidly growing urban areas are drying up. The rivers Ganges, Jordan, Nile, and Yangtze — all dwindle to a trickle for much of the year. In the former Soviet Union, the Aral Sea has shrunk to a quarter of its former size, leaving behind a salt-crusted waste. Water has been a serious issue in the developing world for so long that dire reports of shortages in Cairo or Karachi barely register. But the scarcity of freshwater is no longer a problem restricted to poor countries. Shortages are reaching crisis proportions in even the most highly developed regions, and they're quickly becoming commonplace in our own backyard, from the bleached-white bathtub ring around the Southwest's half-empty Lake Mead to the parched state of Georgia, where the governor prays for rain. Crops are collapsing, groundwater is disappearing, rivers are failing to reach the sea. Call it peak water, the point at which the renewable supply is forever outstripped by unquenchable demand.
This is not to say the world is running out of water. The same amount exists on Earth today as millions of years ago — roughly 360 quintillion gallons. It evaporates, coalesces in clouds, falls as rain, seeps into the earth, and emerges in springs to feed rivers and lakes, an endless hydrologic cycle ordained by immutable laws of chemistry. But 97 percent of it is in the oceans, where it's useless unless the salt can be removed — a process that consumes enormous quantities of energy. Water fit for drinking, irrigation, husbandry, and other human uses can't always be found where people need it, and it's heavy and expensive to transport. Like oil, water is not equitably distributed or respectful of political boundaries; about 50 percent of the world's freshwater lies in a half-dozen lucky countries... www.wired.com
