A pair of articles on the front page of Wednesday’s Los Angeles Times highlighted additional variables relating to ongoing drought concerns in the Golden State.
Bettina Boxall reported that, “Parts of the San Joaquin Valley are deflating like a tire with a slow leak as growers pull more and more water from the ground. The land subsidence is cracking irrigation canals, buckling roads and permanently depleting storage space in the vast aquifer that underlies California’s heartland.
“The overpumping has escalated during the past drought-plagued decade, driving groundwater levels to historic lows in some places. But in a large swath of the valley, growers have been sucking more water from its sands and clays than nature or man puts back for going on a century.
“They are eroding their buffer against future droughts and hastening the day, experts warn, when they will be forced to let more than a million acres of cropland turn to dust because they have exhausted their supplies of readily available groundwater.”
The article noted that, “Until last year, California didn’t have a statewide groundwater law, making it an outlier in the West. The legislation, intended to end unsustainable groundwater use, won’t do that any time soon. Agricultural interests opposed the regulations, which call for the creation of local groundwater agencies that have more than two decades to fully comply.
“In the meantime, it’s easier for growers to keep pumping than rein in their use. ‘Telling people they have to stop irrigating is a huge economic thing,’ said Charles Burt, chairman of the Irrigation Training and Research Center at Cal Poly San Luis Obispo. ‘Guys are going to get their guns out. If you were farming, you wouldn’t take that very lightly.’
“When Burt compares the annual groundwater overdraft in the valley with crop water usage, he figures that 1 million to 1.5 million acres will go out of production in coming years. ‘There are just more straws in there than there is water,’ he said. ‘It’s been going on for a long time.'”
Wednesday’s article added that, “The greatest subsidence related to groundwater extraction ever recorded in the U.S. is on the valley’s west side, where the water table plunged 400 feet in the early and mid-20th century. The accompanying soil compaction caused an area southwest of Mendota to sink more than 28 feet. In a now famous 1977 photo, Poland stood by a telephone pole affixed with signs far above his head indicating where the ground had been in 1955 and 1925.
“The subsidence largely stopped and groundwater levels rebounded in many areas after the arrival of federal and state irrigation deliveries, which provided growers with cheaper, better water.
“But even when the water table recovers, subsided basins can’t hold as much water as they did previously. Soil compaction can permanently reduce the pore space between clay particles, leaving less room for groundwater.”
Ms. Boxall explained that, “It is the economics of having to go deeper and deeper for groundwater that will ultimately force growers to retire land. It’s not that the Central Valley’s thick aquifer will run dry. Scientists estimate that it holds roughly 800 million acre-feet of water that seeped deep into the valley’s sands and clays over millenniums from streams and rivers swollen with runoff from the neighboring Sierra Nevada and coastal ranges.
“Farmers will instead run out of water they can afford to pump.”
In a separate article on the front page of today’s LA Times, Ms. Boxall reported that, “With California heading into another parched year, state officials Tuesday beefed up emergency drought regulations, directing urban agencies to limit the number of days residents can water their yards.
“The move is expected to have little or no effect in most major Southern California cities, which already have watering restrictions. The statewide effects are difficult to gauge, as regulators don’t know how many local agencies lack limits.”
Wall Street Journal writer Jim Carlton also reported on this development and noted that, “State officials said they felt compelled to adopt the new rules, and extend others passed last summer, including a ban on allowing sprinkler runoff into streets, because of the growing severity of one of California’s worst droughts. Reservoirs in the state sit at less than 60% capacity following a fourth consecutive dry winter, which has left the state’s mountain snowpack at a record low of less than 20% of the historical average.
“Officials said that while Californians have largely heeded Gov. Jerry Brown’s calls to conserve more—saving enough since last June to meet the needs of a city of two million for a year—it hasn’t been enough. In part, the water managers are frustrated by statewide surveys that show a declining conservation rate recently after initial strong compliance.”
Meanwhile, Adam Nagourney reported in Wednesday’s New York Times that, “The rainy season drove into California in December with wet and windy promise: soaking rain, snow, dark gray skies and a flash of hope that the drought that has scorched this region had run its course. And then came January — with record high temperatures and record low rainfall.
“And now, as the end of the official rainy season approaches — this state gets 90 percent of its water from December through April, most of it in December and January — California is facing a punishing fourth year of drought. Temperatures in Southern California soared to record-high levels over the weekend, approaching 100 degrees in some places. Reservoirs are low. Landscapes are parched and blighted with fields of dead or dormant orange trees. And the Sierra Nevada snowpack, which is counted on to provide 30 percent of the state’s water supply as it melts through early summer, is at its second-lowest level on record.”
The New York Times article also included a link to this video: