An estimate cited by the Washington Post is that 65 percent of the fresh water used in the state in 2014 came from groundwater, which is up from the annual average use during non-extreme drought times of 40 percent. And the water table recently has been declining by two feet per year in the agriculturally productive Central Valley.
In a drought, groundwater has been the backup to low volumes of surface water. It is a critical situation for many communities and farmers. In a February report, AgProfessional quoted sources as explaining how the California Department of Water Resources on Jan. 31 announced water deliveries from the state’s largest canal system to southern California agricultural areas would be cut to zero for the first time in the project’s 54-year history affecting thousands of farmers, as well as 24 municipalities. This essentially meant more groundwater would have to be used.
It is suggested that groundwater supplies required thousands of years to reach their highest levels and, therefore, will require decades to replenish even if major pumping of water was stopped.
It has only been within the last couple years that new regulation on groundwater pumping has been seen as a necessity. An extensive groundwater regulation bill was passed by the California legislature in 2014, but many provisions of the regulations don’t take affect for years.
