A new study finds groundwater losses from the Colorado River basin appear massive enough to threaten long-term supplies for the seven states and parts of Mexico that draw water from the basin.
Researchers from NASA and the University of California, Irvine used satellites to assess what the report’s lead author called the "shocking'' depletion of the groundwater. Since 2004, researchers said, the basin has lost 53 million acre feet of water — that’s enough to supply more than 50 million households for a year or nearly fill two Lake Meads, the nation's largest water reservoir.
The study found three-quarters of the losses involved groundwater, and that the extent of that loss may pose more of a threat to the western U.S. water supply than previously thought.
The Colorado River basin supplies water to about 40 million people and 4 million acres of farmland in parts of Arizona, California, Colorado, New Mexico, Nevada, Utah and Wyoming, as well as people and farms in part of Mexico.