California drought may have pushed parts of the Sacramento Valley aquifer toward permanent collapse

Around a quarter of the U.S. food supply is grown in California's Central Valley.

Most of its crops, like rice, fruit trees and nut trees, are water-intensive and require extensive groundwater pumping during droughts.

Over time, heavy water extraction has contributed to changes in the aquifer systems under the San Joaquin and Sacramento valleys.

Although some of these changes can be reversed, a new study, published in the Proceedings of the National Academy of Sciences, indicates that large parts of the Sacramento Valley may have undergone irreversible ground compaction during recent droughts, leading to a permanent loss of groundwater storage. ...