Central Valley’s Groundwater Lost 25 Cubic Miles due to Drought
A study conducted in May of this year by a group led by UCLA professors revealed that the Central Valley lost 25 cubic miles of groundwater during the drought that ran from 2012 through last year. The geologists studied the loss of groundwater in the Central Valley, where there are an estimated 10,000 private wells siphoning water from aquifers below the arid but soil-rich valley. To put things into perspective, the groundwater lost in the most recent drought would fill a tank 25 miles long, 25 miles wide and 25 miles high, which is more than 44 Lake Tahoes. Part of what accounted for the water loss was the fact that the drought coincided with a switch from traditional row crops to high-value but water-dependent crops like almonds, pistachios and walnuts. Dennis Lettenmaier, the UCLA professor of geography who led the study, stated:
Pumping groundwater during a drought is not an unreasonable strategy. But the problem is that to have a sustainable system you have got to replenish it at some point, and there essentially is no plan to do that.
Groundwater pumping remains a contentious issue in the Central Valley because farmers are dependent on water allocations from the Sierra Nevada runoff and extra water from the Colorado River Basin. The massive groundwater extraction that occurred in Central Valley worried environmentalists, scientists and public officials, because over pumping can result in compaction, water-storage loss and dry wells in agricultural and residential areas near the valley. California’s Central Valley comprises about 18,000 square miles, spanning the center of the state from the coastal mountains to the Sierra Nevada Mountains. A solution needs to be created to solve these issues because California cannot afford to lose more groundwater.