Land sinking as much as 2 inches per month in San Joaquin Valley

Sinking land has occurred for decades in California because of excessive groundwater pumping during dry years, but NASA data released Wednesday by the state's Department of Water Resources shows the pace has dramatically quickened as the state endures its fourth year of drought.

The study done by NASA's Jet Propulsion Laboratory shows the ground is sinking nearly two inches each month in some places, placing roads, bridges and vital canals that deliver water throughout the state at growing risk of damage.
"We are pumping at historic levels," said Mark Cowin, head of the California Department of Water Resources, adding that groundwater levels are dropping to record levels — up to 100 feet lower than previously recorded.

Gov. Jerry Brown signed historic legislation last year that requires monitoring of groundwater pumping. However, local officials have until 2020 and in some cases until 2022 to write their management plans, so it could take another decade or two before California has a handle on groundwater use, Cowin said.

"I don't think we can end overdraft or subsidence overnight," he said. "We do need to take action."

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California land quickly sinking in drought costs farmers