After years of unrelenting drought, federal forecasters reported there are better-than-even odds that the nation's largest reservoir will decline into shortage conditions by 2020, forcing Arizona, Nevada and Mexico to reduce their Colorado River water use.
A new study by scientists from NASA and the University of California, Irvine, has found that over 75 percent of the water loss in the drought-stricken Colorado River Basin since late 2004 came from underground resources. The extent of groundwater loss may pose a greater threat to the water supply of the western United States than previously thought.