Running Out of Water

From SciAm.com:

The Ogallala Aquifer:
Saving a Vital US Water Source

Key Concepts

• If spread across the U.S. the aquifer would cover all 50 states with 1.5 feet of water
• If drained, it would take more than 6,000 years to refill naturally
• More than 90 percent of the water pumped is used to irrigate crops
• $20 billion a year in foodand fiber depend on the aquifer

On America’s high plains, crops in early summer stretch to the horizon: field after verdant field of corn, sorghum, soybeans, wheat and cotton. Framed by immense skies now blue, now scarlet-streaked, this 800-mile expanse of agriculture looks like it could go on forever.

It can’t.

The Ogallala Aquifer, the vast underground reservoir that gives life to these fields, is disappearing. In some places, the groundwater is already gone. This is the breadbasket of America—the region that supplies at least one fifth of the total annual U.S. agricultural harvest. If the aquifer goes dry, more than $20 billion worth of food and fiber will vanish from the world’s markets. And scientists say it will take natural processes 6,000 years to refill the reservoir.

The challenge of the Ogallala is how to manage human demands on the layer of water that sprawls underneath parts of eight states from South Dakota to Texas. As landowners strive to conserve what’s left, they face a tug-of-war between economic growth and declining natural resources. What is happening here—the problems and solutions—is a bellwether for the rest of the planet. Read more...