Friday, December 11, 2015

Overpumping is draining the nation's aquifers; water levels down 64% in past two decades

Decreasing groundwater levels are depleting the nation's aquifers, draining farmers of much needed water and leading to increased costs for well owners, water utilities and the general public, Ian James and Steve Reilly report for USA Today and The Desert Sun. Overpumping is being blamed on agriculture—which accounts for nearly two-thirds of the nation’s use of fresh groundwater—and more water being drained for cities, expanding development and industries. Overall, more water is being pumped from the ground than cane be replenished.

"Nationwide, water levels have declined in 64 percent of the wells included in the government database during the past two decades," James and Reilly write. "The average decline among decreasing wells has been more than 10 feet, and in some areas the water table has dropped more than 100 feet during that period—more than 5 feet per year." Since the beginning of the 20th century, the U.S. has lost an estimated 1,000 cubic kilometers of water from the nation’s aquifers. (USDA map)

Decreasing groundwater levels are leading to increased costs for well owners, water utilities and the general public, James and Reilly write. "As water levels drop, more energy is required to lift water from wells, and those pumping bills are rising. In areas where aquifers are being severely depleted, new wells are being drilled hundreds of feet into the earth at enormous cost. That trend of going deeper and deeper can only go on so long. When groundwater levels fall to precarious lows and wells are exhausted, farming businesses can suffer. And in particularly hard-hit communities, such as parts of California, homeowners have been left relying on tanker trucks to deliver their water."

One of the nation's biggest sources, the Ogallala Aquifer, is being severely depleted, James and Reilly write. The Ogallala covers 174,000 square miles in parts of South Dakota, Wyoming, Nebraska, Colorado, Kansas, Oklahoma, New Mexico and Texas and "makes possible about one-fifth of the country’s output of corn, wheat and cattle." With water drying up, "some farmers are adapting by switching to different crops. Others are shutting down their drained wells and trying to scratch out a living as dryland farmers, relying only on the rains." (USA Today map: Orange areas have lost 5 to 15 feet of water, yellow 0 to 4 feet)

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