News Earth Irrigation draining California groundwater at ‘unsustainable’ pace The GRACE satellites have tracked water movement from the Central Valley since 2003 Share this:FacebookTwitterPocketRedditPrintEmail By Sid Perkins December 15, 2009 at 4:18 pm This article is only available to Science News subscribers. Subscribers, enter your e-mail address to access our archives. Client key* E-mail* Log in Not a subscriber? Science News is a nonprofit. Support us by subscribing now. Subscribe