California’s Central Valley Is Sinking As Farmers Suck Water From Underground

All the water news out of California has been bad lately. Of all the areas that have been hit by drought, this western state seems to have been hit hardest.

Last year, the government passed a statewide water use law, for the first time ever, in the face of the decade-long drought. Recently, NASA scientist Jay Famiglietti warned that the state has only a one-year water supply left. Now, hydrologists have confirmed that the farm-rich Central Valley is sinking at the rate of half-a-foot to a foot yearly.

Water-use regulation has been fiercely resisted, particularly by the valley’s farmers. Even though a poll in February showed that 94% of the state’s voters think the drought is “serious,” 61 percent of them want reductions to be voluntary. The problem with that is — it doesn’t work.

There are over 100,000 wells up and down the Central Valley. Farmers have been pumping out as much water as they like, basically free of any monitoring. More water comes out of the underlying aquifer than goes in. The result is that the land is collapsing. Even if the drought ends, there’s no longer room underground for adequate storage of accessible water.

Some of the water in the aquifer seeped into it 10,000 to 20,000 years ago. Farmers have drawn much of it out in the last 100 years, particularly in the last decade. With a shrinking capacity for storage underground, there is little to no protection from future droughts. It’s estimated that over a million acres of cropland will turn to dust in the near future.

Farmers know they are the problem. Nevertheless, they resist regulation. Charles Burt of Cal Poly, who researches and trains in the area of irrigation, explains why:

Telling people they have to stop irrigating is a huge economic thing. Guys are going to get their guns out. If you were farming, you wouldn’t take that very lightly.

The idea that the Central Valley is sinking isn’t new. In the first half of the last century, an area south of Mendota sank 28 feet. However, the depth and breadth of the problem is newly alarming.

The ultimate outcome isn’t that the aquifer will run dry, but it has to be drawn out from a deeper and deeper level. The cost of going after such deep water is prohibitive and will lead to farmers abandoning the land. How could they sell farm land that has no water?

Almond grower Charlie Pitigliano described the problem in his own terms. In the last two years, he’s had to drill half a dozen new wells, some of which are twice as deep as the old ones. The cost was $1.5 million dollars. The water the wells drew up was too alkaline for the crops, so he had to install a water treatment system — another $50,000.

Pitigliano is part of a local committee that has to figure out how to implement the state groundwater law. While acknowledging that the farmers have to learn to regulate themselves in order to save the valley, he stresses over the fact that some will be cut off. He wonders, “Who is going to say: ‘Turn your pump off?’”

It’s likely to be him, and it won’t be pretty.


Feature photo from U.S. Geologic Survey.