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A Believer's
Guide to Disaster Preparedness
Time, Water Running
Out for America's Biggest Aquifer
(April 21) -- In 1823, a government
surveyor named Stephen Long was working to map out the Great Plains, an
expanse of land acquired along with the Louisiana Purchase of 1803. He was
unimpressed by what he saw. As his geographer wrote in the report that
accompanied the expedition:
I do not hesitate in giving the
opinion that it is almost wholly unfit for cultivation, and of course,
uninhabitable by a people depending upon agriculture for their subsistence.
Long would have been shocked to see
what the region looks like today -- not merely fit for cultivation, but in
fact one of the most fertile and productive areas of the world. Since World
War II, dramatic leaps in technology have allowed farmers to pump
groundwater for irrigation and extend America's breadbasket through the
entire Great Plains, transforming what Long called "The Great American
Desert" into an expanse of green circles defined by the reach of central
pivot irrigation systems.
But that water is not infinite, and many are becoming concerned that Great
Plains agriculture is a more precarious proposition than it appears --
meaning Long's report may have been not just a description, but a
prediction.
That groundwater for irrigation comes
from the Ogallala Aquifer, a massive underground lake that stretches from
southern South Dakota through northern Texas, covering about 174,000 square
miles. It is being drained at alarming rates, and some places have already
seen what happens when local levels drop below the point where water can no
longer be pumped.
"You go to areas where the aquifer has been depleted, [they] look pretty
poor now," David Brauer, program manager for the U.S. Department of
Agriculture's Agricultural Research Service Ogallala Aquifer Program, told
AOL News. "And it only takes a few years.
"The magnitude of this is incredible," he continued. "We're talking about,
for the last 20 years, 20 percent of the irrigated acreage of this nation is
over the Ogallala."
For an idea of what a severe drought could do to the communities of the
Great Plains, consider the Dust Bowl of the 1930s, when gigantic "black
blizzards" ravaged farms and forced thousands of families to give up their
land and try to make a living elsewhere.
But the implications of ceasing irrigation on the Great Plains go far beyond
local communities. The farming areas fed by the Ogallala supply such large
quantities of grain that any drastic changes to that economy would ripple
across the world -- as seen in 2007, when fuel costs drove up corn prices
and sparked a food crisis in other countries, most notably Mexico.
People have been warning about the
aquifer's depletion for years, but coordinating conservation programs among
farmers has proved difficult. Recently, Texas has imposed state controls on
the amount of groundwater that farmers can pump, requiring 16 groundwater
districts to each provide a target for an acceptable groundwater level in 50
years.
Such measures, however, are mostly designed to delay the inevitable, since
the recharge rate for the Ogallala Aquifer is small enough to be considered
negligible. And so, Brauer says, as a natural resource the Ogallala is
comparable to a vein of coal: What you take out doesn't get put back in.
"All we're doing is buying time," he says.
Buying time is important -- it will allow farmers to develop dry-farming
techniques and give the biotech industry a chance to deliver on the promise
of drought-resistant crops. But without groundwater irrigation, crop yields
will almost certainly drop, and the local, national and global economies
will have to adjust.
http://www.aolnews.com/earth-day/article/time-water-running-out-for-ogallala-americas-biggest-aquifer/19446923?ncid=webmaildl1&sms_ss=email
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