This page contains a Flash digital edition of a book.
EVERYWHERE… But Will There Be Enough?


WATER, WATER by Sandra Postel


For at least three decades, Americans have talked about our uncertain energy future, but we’ve mostly ignored another worrisome crisis—water.


C


heap and seemingly abundant, water is so common that it’s hard to believe we could ever run out of it. Ever since the Apollo 8 astronauts photographed Earth from space in 1968, we’ve had the image of our home as a strikingly blue planet, a place of great water wealth. But of all the water on Earth, only about 2.5 percent is fresh—and two-thirds of that is locked up in glaciers and ice caps. Less than one hundredth of 1 percent of Earth’s water is fresh and available. Across the United States and around the world, we’re already reaching or overshooting the limits of Earth’s natural replenishment of fresh water through the hydrologic cycle. The Colorado and Rio Grande rivers are now so over-tapped that they discharge little or no water into the sea for months at a time. According to the U.S. Geological Survey (USGS), the massive Ogallala Aquifer, which spans parts of eight states, from southern South Dakota to northwest Texas, and provides 30 percent of the groundwa- ter used for irrigation in the country, is steadily being depleted. In much of the world, we’re growing food and supplying water to communities by over-pumping groundwater. This creates a potential crisis in the food economy: We are


meeting some of today’s food needs with tomorrow’s water.


The Changing Climate Equation


Due to climate change, we may no lon- ger be able to count on familiar patterns of rain and snow and river flow to refill our urban reservoirs, irrigate our farms and power our dams. While farmers in the Midwest were recovering from the spring flood of 2008 (in some areas, the second “100-year flood” in 15 years), farmers in California and Texas allowed cropland to lie fallow and sent cattle to early slaughter to cope with the drought of 2009.


In the Southeast, after 20 months of dryness, then-Georgia Governor Sonny Perdue stood outside the state capitol in November 2007 and led a prayer for rain. Two years later, he was pleading instead for federal aid, after intense rainfall near Atlanta caused massive flooding that claimed eight lives. This year again saw record regional precipitation, this time produc- ing epic flooding in the Mississippi and Missouri river basins.


Climate scientists warn of more extreme droughts and floods and changing precipitation patterns that


will continue to make weather, storms and natural disasters more severe and less predictable. As a policy forum in the journal Science notes, the historical data and statistical tools used to plan billions of dollars worth of annual glob- al investment in dams, flood control structures, diversion projects and other big pieces of water infrastructure are no longer reliable. Yet today’s decisions about using, allocating and managing water will determine the survival of most of the planet’s species, including our own.


Shifting Course


For most of modern history, water man- agement has focused on bringing water under human control and transferring it to expanding cities, industries and farms via dams, large water-transfer projects and wells that tap underground aquifers. Major water programs have al- lowed cities like Phoenix and Las Vegas to thrive in the desert, the expansion of world food production, and rising living standards for hundreds of millions. But globally, they have worsened social inequities as tens of millions of poor people are dislocated from their homes to make way for dams and canals, while hundreds of millions in downstream communities lose the currents that sustain their livelihoods.


Such approaches also ignore wa- ter’s limits and the value of healthy eco- systems. Today, many rivers flow like plumbing works, turned on and off like water from a faucet. It’s tougher for fish, mussels, river birds and other aquatic life to survive; a 2008 assessment led by the USGS found that 40 percent of all fish species in North America are at risk of extinction.


Meanwhile, many leaders and localities are calling for even bigger versions of past water management strategies. By some estimates, the volume of water relocated through river transfer schemes could more than double globally by 2020. But mega- projects are risky in a warming world, where rainfall and river flow patterns are changing in uncertain ways and


16


New Jersey North NANorthNJ.com


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32