Pumping water from the ground in response to severe droughts in California has led to another major problem: vast areas of sinking ground in the Central Valley. In some parts land is sinking at a rate of two inches per month, according to The Guardian, “collapsing into what scientists describe as a ‘cone of depression.’”
The sinking has been caused by farmers racing to the bottom, drilling new and deeper wells in an effort to stay in business after the state of California cut off their access to rivers and reservoirs because of the drought. Since the land is rich in clay, pumping pulls water out of the clay pores, not only causing them to collapse but making it impossible to refill and act as a natural reservoir should heavy rains come in the future.
Chase Hurley, manager of the San Luis Canal Company, says, “The issue is the amount of deepwater pumping below the clay. That is what is causing the subsidence. The land is sinking as they extract the water below the clay; there is a pressure differential. It is pulling the water out of the clay layer, and when it does, the clay collapses. And as it collapses, it brings everything with it.”
Finding new ways to deal with water shortages and addressing the now sinking ground is especially critical for this area, as the Central Valley produces 40 percent of the country’s fruit, nuts, and other table foods.