Groundwater Mining Sinking San Joachin Valley

San Jose Mercury News:

So wet was the San Joaquin Valley of Steve Arthur's childhood that a single 240-foot-deep well could quench the thirst of an arid farm.
Now his massive rig, bucking and belching, must drill 1,200 feet deep in search of ever-more-elusive water to sustain this wheat farm north of Bakersfield. As he drills, his phone rings with three new appeals for help.
"Everybody is starting to panic," said Arthur, whose Fresno-based well-drilling company just bought its ninth rig, off the Wyoming oil fields. "Without water, this valley can't survive."
When water doesn't fall from the sky or flow from reservoirs, there's only one place to find it: underground. So, three years into a devastating drought, thirsty Californians are draining the precious aquifer beneath the nation's most productive farmland like never before, pitting neighbor against neighbor in a perverse race to the bottom.
The rush to drill is driven not just by historically dry conditions, but by a host of other factors that promote short-term consumption over long-term survival -- new, more moisture-demanding crops; improved drilling technologies; and a surge of corporate investors seeking profits for agricultural ventures.
Now those forces are renewing an age-old problem of environmental degradation: Decades ago, overpumping sunk half of the entire San Joaquin Valley, in one area as much as 28 feet. Today new areas are subsiding, some almost a foot each year, damaging bridges and vital canals.

Another interesting note:

"I've got some of the best land in the nation -- 50 feet of topsoil -- that is sitting vacant if I can't get water," said Thomas Kaljian, of Los Banos, who owns almond orchards on the San Joaquin Valley's west side. "This is the breadbasket of the nation, and we're strangling it."
The signs of the valley's relentless thirst are everywhere. An analysis by this newspaper shows a dramatic jump in well construction in seven San Joaquin Valley counties in 2013, with an even sharper increase this year as Gov. Jerry Brown declared a drought emergency:

Also, some history of agriculture in the Valley:

The Central Valley, home to the world's largest swath of ultra-fertile Class 1 soil, is the backbone of California's $36.9 billion a year, high-tech agricultural industry. Its 6.3 million acres of farmland produce more 350 crops, from fruits and vegetables to nuts and cotton, representing 25 percent of the food on the nation's table.
Generations ago, agriculture was at the mercy of Mother Nature.
"What you got out of the sky was what predicated what your crops would be," said Pat Hillman, 86, whose grandfather Jefferson Davis Heiskell moved to Tulare in 1886 to start a grain warehouse to store the area's wheat, barley and sorghum.
Eventually, farmers dug crude canals to channel water to their fields from Tulare Lake, once larger than Lake Tahoe, and from the abundant shallow artesian wells that flourished during wet seasons. But by 1898, the lake was drained dry, and the only sign left of the shallow wells is a slab of granite set by the Pixley Women's Club in an abandoned cattle trough to commemorate the area's long-gone natural fountains.

New technologies soon made it possible to tap into the deep underground water basin. Improvement of drilling techniques and gasoline-powered pumps, then the invention of the deep well turbine pump in 1930, drove wells down more than 300 feet.

More intensely irrigated row crops followed, with acreage made feasible by mechanical harvesting and refrigerated railroad transportation. The federal system of aqueducts, pumps, canals and dams -- the largest water development project in the United States, completed in 1949 -- spurred more agricultural growth.
Soon, every acre was valuable, and thirsty -- especially when it didn't rain, and the demand for groundwater grew.
"Now you don't see any piece of dirt that don't have something on it anymore," Arthur said. "Before, you used to just grow in the winter. Now, to make any money, you better have crops all year round."

Agriculture in the Valley is a race to the bottom.  To the bottom of the aquifer.  The story says that thousands of acres are still being converted to almonds, in spite of the constant irrigation they require.  This will not end well.  Eventually, some of the most productive farmland in the world will be reduced to seasonal, dry-land farming. It's a damn shame that topsoil was left in a desert.