This issue brief examines water use in California agriculture, changes over time and across crops, and the state’s agricultural economics, using statewide data and publicly available information. California agriculture is one of the world’s most productive agricultural regions, supplying U.S. and international markets with more than 350 different farm products.

Agricultural water use varies substantially from year to year, driven by changes in weather, irrigated acreage, and crop type.  Irrigated acreage and applied water use have shifted toward permanent orchard and vineyard crops, making agriculture more vulnerable in the face of climate change and decreasing water supply reliability.  At the same time, the economic productivity of water has grown, with agricultural revenue per acre-foot more than doubling since 1960, adjusted for inflation. 

Through this brief, we aim to provide a clear understanding of agricultural water use trends and to equip researchers, policymakers, advocates, and other stakeholders with the information needed to drive meaningful policy change and strengthen agricultural resilience in the face of a changing climate. 

• Since 2007, agricultural water use has declined by an average of 0.27 MAF per year, reaching 31.5 MAF in 2022.  Overall, agricultural water use has varied substantially over time, ranging from a low of 25.7 MAF in 1992 to a high of 37.0 MAF in 2008. 

• The economic productivity of agricultural water has more than doubled. In 1960, an acre-foot of agricultural water generated about $650 in revenue; by 2022, that figure had risen to about $1,400 per acre-foot, in inflation-adjusted dollars. 

• Irrigated acreage has stayed relatively stable, even as crop types have shifted. Since the early 1970s, total irrigated crop acreage has varied by just over 10%, ranging from 8.9 million to 9.9 million acres and averaging 9.3 million acres.  

• Water use and irrigated acreage have shifted sharply toward orchard crops and vineyards. Between 1998 and 2022, applied water use for field and vegetable crops declined by 21% and 33%, respectively, while applied water use for orchard and vineyard crops increased by approximately 175% and 120%. These trends are mirrored in irrigated acreage as well and by 2022, orchard crops accounted for more than one-third of the state’s total irrigated acreage. 

• About 15% of the state’s irrigated acreage and more than 20% of its applied agricultural water are dedicated to feeding livestock. California’s dairy industry is the largest in the nation and consistently the largest contributor to the state’s agricultural revenue, exceeding $11.5 billion in sales in 2022.