For many decades, California has been the leading agricultural state in terms of the value of agricultural goods, marketed, generating $58 billion in agricultural cash receipts in 2023, outpacing second-place Iowa by more than $13 billion. Of that $58 billion figure, about 55 percent is derived from production of specialty crops such as fruit, vegetables, and tree nuts.
According to the California Department of Water Resources, more than nine million acres of the state’s crop land is irrigated, most of it for raising the high-value crops mentioned above. This irrigated area accounts for just over a third of California’s cropland acres. As of 2023, about half of the water used for irrigation in California was drawn from groundwater directly underneath the farming operation, about 14 percent from surface water sources within the farm’s boundaries, and the remaining 36 percent was derived from off-farm water sources of all types. This data was provided under the 2023 Irrigation and Water Management Survey collected by USDA’s National Agricultural Statistics Service (NASS) that is supplemental to the Census of Agriculture surveyed and reported every five years.
Over the last century, California has endured seven separate droughts lasting three or more years. Especially during the drought that lasted for five years between 2012 and 2016, federal and state authorities had to cut back on the allocations of surface water that California farmers had relied on for irrigating their fields, leading to an acceleration of the drilling of groundwater wells in heavily agricultural regions, such as the Central Valley. The Valley is an area that stretches from Redding in Shasta County in the north to Bakersfield in Kern County to the south, encompassing roughly 20,000 square miles. In terms of surface area, this represents about 12 percent of California.
More than 250 different crops are grown within the Central Valley, most of them high-value crops such as almonds and grapes–both water-intensive crops–as well as a robust dairy sector. Tulare County is home to an estimated 450,000 dairy cows, making it the largest county for dairy production in the United States. Farmers in this region account for an estimated $17 billion in agricultural receipts each year, or nearly 30 percent of the state’s total.
Another water-intensive crop grown in California is rice, which is found primarily in the Sacramento Valley in the northern end of the Central Valley. The state is typically the second leading producer of rice in the United States, trailing only Arkansas. Total area planted has fallen by more than 20 percent since its peak right before the extended drought that started in 2012, falling from an average of 547,000 acres between 2007-11 to an average of 425,000 acres between 2020 and 2024.
In the midst of the multi-year drought in 2010’s, several counties in the Central Valley reported a sharp increase in the number of wells drilled between 2013 and 2014, including Fresno (up 14 percent), Tulare (up 64 percent), Merced (up 159 percent), Madera (up 118 percent), Stanislaus (up 20 percent), while a few other counties (Kern, Kings, and San Joaquin) showed modest declines.
This rapid increase in drilling of wells in the Central Valley as well as in other parts of the state, as well as concern over the fact that agricultural well drillers were having to go much deeper to find groundwater, led to demand for the state government to take some action to curtail the drawdown rate of the state’s aquifers. In 2014, the state enacted the Sustainable Groundwater Management Act, which put in place a plan to create local groundwater sustainability agencies (GSA’s) in key agricultural regions already facing considerable drawdowns in their groundwater levels. Those agencies were tasked to provide technical assistance and guidance on best management practices to help local farmers to gradually reduce their use of groundwater for their operations over a 20-year phase-in period. The law applies primarily to producers in the Central Valley, as well as scattered other regions such as in Ventura County on the Pacific Coast northwest of Los Angeles and parts of Riverside County that stretch from east of Los Angeles to the Palm Springs area.
Ten years after SGMA was enacted, 120 groundwater sustainability plans (GSP)’s have been submitted to the California Water Resources Control Board (WRCB), covering 98 percent of the state’s groundwater use. Most of the GSA’s now have the capability of monitoring local groundwater conditions and are in the process of undertaking their first five-year evaluations.
Not all regulated regions have met their obligations under SGMA. In April 2024, the WRCB put Kings County under probationary status for failing to prepare and submit a plan for controlling groundwater pumping. That regulatory action is currently on hold due to lawsuits filed in state court, but the relevant GSA’s in the county are finally taking steps to address SGMA requirements, seeking guidance from other GSA’s in the Central Valley which have submitted plans to the Board and gotten them approved.
California farmers have already taken significant strides to improve the efficiency of their irrigation water usage over the last few decades. Since 2008, the use of more efficient irrigation systems, such as drip, trickle, or other micro-flow systems in California has increased by more than 233 percent, and California farmers accounted for more than two-thirds of the use of such systems nationally as of the 2022 Census of Agriculture. Interestingly, total acreage irrigated with such systems in the rest of the country actually fell over the same period by 15 percent.
Numerous small towns in California, particularly in the Central Valley, are facing crises as their municipal wells have either gone dry or are on the verge of doing so. As of 2022, there were nearly 400 such communities whose water systems have been determined by the state to be ‘failing’. Many have sought and received emergency assistance from the state to deal with this problem, but due to the number of communities affected, the backlog of applications has been growing and the time for approval of funding has been lengthening.
