Across the country, water supplies are under duress. Demand of surface water often surpasses availability, compelling the use of groundwater. In California, groundwater normally accounts for 40% of the total water supply and more than 60% in dry years. Some communities rely solely on groundwater for their water needs.[1] Parts of the state have seen groundwater withdrawals exceed replenishment, especially in the Central Valley region where agriculture is the cornerstone of the economy, and the area’s water usage accounts for approximately one-fifth of the nation’s total groundwater demand.[2] Now, the state is poised to intervene to safeguard this vital resource.

In 2014, California enacted the Sustainable Groundwater Management Act to protect groundwater resources, mandating that local water agencies form groundwater sustainability agencies that would develop Groundwater Sustainability Plans (GSP) to bring their groundwater basins into balance by 2040. The 20 most depleted basins were required to submit plans in 2020. However, after two rounds of review, six basin plans have been determined incomplete, all located within the San Joaquin Valley, an agricultural area vigorously pumped for decades.

The Tulare Lake Subbasin is the first in which the State Water Resources Board may intercede, where 27 wells went dry last year, approximately 700 others are vulnerable, and levees have been necessary to protect areas from flooding where subsidence has occurred by as much as six feet.[3] The board recently released a probationary hearing notice for the subbasin scheduled for April 2024. If placed on probation, farmers would be required to report pumping volumes and pay fees based on those volumes.

As local agencies navigate decreasing supplies and increasing pressure to conserve, some options will challenge communities’ economic, societal, and environmental stability. However, these agencies must align their GSPs with a commitment to sustainable groundwater management and future water resiliency, or the state will do it for them.

[1] Karlamangla, Soumya. “The Dire Consequences of Depleting California’s Groundwater.” The New York Times, The New York Times, 30 Aug. 2023, www.nytimes.com/2023/08/30/us/california-groundwater-depletion.html.

[2] Faunt, C.C., ed., 2009, Groundwater Availability of the Central Valley Aquifer, California: U.S. Geological Survey Professional Paper 1766, 225 p.

[3] Zhong, Raymond. “California Moves Closer to Imposing First Limits on Groundwater Use.” The New York Times, The New York Times, 12 Oct. 2023, www.nytimes.com/2023/10/12/climate/california-groundwater-tulare-lake.html.