declining Colorado River Basin groundwater reserves

Colorado Basin groundwater declines, courtesy Chris Austin

Colorado Basin groundwater declines, courtesy Chris Austin

New data from NASA’s GRACE satellite, which scientists use to track changes in groundwater storage, shows some remarkable declines in the Colorado River Basin, according to a recent presentation by Jay Famiglietti of UC Irvine to a California legislative committee (huge thanks to Chris Austin for catching this and bringing it to my attention):

“Unfortunately, looking beyond our borders isn’t going to help – just like in California, the Colorado River basin is in long term decline,” Mr. Famiglietti said, presenting a slide showing the total water storage for the Colorado River basin. “When we separate the surface water storage in Lake Powell and Lake Mead and the groundwater storage, we get the graph on the bottom, which is showing us what’s happening. With Lake Powell and Lake Mead’s storage, not much of a trend albeit there’s a recent decline, but the important thing to recognize here is that the groundwater losses from the Colorado River Basin in this time period completely swamped the losses and dominated the total water storage change. They are far bigger than the surface water changes. The message is that we pay all this attention to surface water management, and while no one’s watching, the groundwater is being depleted at a rapid clip.”