The San Joaquin Valley is the agricultural powerhouse of the United States and California. California accounts for an eighth of U.S. farm sales, largely because it produces high value fruit and nut, vegetable and melon, and horticultural specialty (FVH) crops such as nursery products and flowers. Over three-fourths of the state's $37 billion in farm sales in 2010 were crop commodities, and almost 90 percent of the $28 billion in California crop sales represented labor-intensive FVH commodities.

About half of California's farm sales and farm employment are produced in the eight-county San Joaquin Valley with four million residents that stretches from Stockton in the north to Bakersfield in the south. The leading U.S. farm county is Fresno, which had farm sales of almost $6 billion in 2010.

More California farmers switch to almond growing, update on Sacramento-San Joaquin Delta water

  • Font size: Larger Smaller
  • Subscribe to this entry
  • Print


Almonds are irrigated with 3.5 acre feet or 42 inches of water, and the typical 124 almond trees per acre yield an average 2,270 pounds of nuts. One cubic foot of water is 7.5 gallons, and one acre is 43,560 square feet, so 502 gallons of water are used to produce a pound of almonds: (7.48 x 3.5 x 43,560 )/2,270 = 502. With about 380 almonds per pound, each almond requires about 1.3 gallons of water.

California's acreage of long-staple Pima cotton declined as more farmers switched to almonds. California had over 300,000 acres of Pima cotton in 2011, and fewer than 100,000 acres in 2015. Despite cotton yields of over 1,200 pounds per acre, nuts and processing tomatoes require less water per dollar of revenue.

Over 70 percent of California grapes and almonds are irrigated with drip or a similar low-water technology. However, less than 10 percent of the alfalfa and corn used to feed dairy cows uses water-saving technologies; flood irrigation is typical.

A Fresno State study ( focused on the effects of the drought in the eight-county San Joaquin Valley, emphasizing that areas most dependent on surface water suffered most. The report called for water budgeting, that is, recognizing the true value of water and pricing it accordingly.


The Sacramento-San Joaquin Delta is a 720,000-acre network of islands and canals that acts as the hub of the state's water system, using pumps to draw river water into canals that move the fresh water south before it can flow under the Golden Gate bridge and into the Pacific Ocean. Delta water accounts for 15 percent of the above-ground water used in California, and is crucial for farmers on the west side of the San Joaquin Valley.

Most of California's surface water arrives as mountain snow in winter and flows into dams as it melts. The water is then moved south via the Sacramento river to the delta and pumped via canals to the San Joaquin Valley and Los Angeles. The 700-mile California Aqueduct takes water almost 2,000 feet over the Tehachapi Mountains to Los Angeles.

Pumping changed the ecosystem of the delta, leaving it saltier in ways that favored some species over others, endangering some traditional fish such as Chinook salmon. The fish versus food question arises because the federal and state agencies that manage the pumps are required by law to protect endangered fish, even if the result is less water for agriculture.

The Delta-area Byron Bethany Irrigation District was fined $1.5 million in July 2015 for diverting over 2,000 acre feet of water from the Delta in June. The State Water Resources Control Board has hired additional inspectors to check for illegal water diversions.

Across the western United States the U.S. Bureau of Reclamation operates 476 dams, 348 reservoirs and 8,116 miles of aqueducts that capture rain and melting snowpack and direct it to cities and farms. Created in 1902, the Bureau's mission was to encourage the settlement of the western states.

Some speculators believe that fresh water will be the oil of the 21st century, especially in arid California. Cadiz owns 34,000 acres of land in the Mojave Desert that has ground water beneath that is now used to irrigate grapes and lemons. It aims to "mine" the water and pipe it to southern California with money raised on Wall Street.

Some of the money raised to sell private water to public agencies in the U.S. is from Europe, where private and for-profit water systems are common.

This post was an excerpt of the most recent Rural Migration News published in October 2015.

Rural Migration News summarizes the most important migration-related issues affecting agriculture and rural America. Topics are grouped by category: Rural America, Farm Workers, Immigration, Other and Resources.


There are two editions of Rural Migration News. The paper edition has about 10,000 words and the email version about 20,000 words.

Distribution is by email. If you wish to subscribe, send your email address to ruralmigrationnews-subscribe [at} Current and back issues may be accessed at


The paper edition is available by mail for $30 domestic and $50 foreign for one year and $55 and $95 for a two-year subscription. Make checks payable to Migration Dialogue and send to: Philip Martin, Department of Ag and Resource Economics, University of California, Davis, California 95616 USA.

in Agriculture Hits: 2102 0 Comments
Philip Martin is Professor of Agricultural and Resource Economics at the University of California- Davis, chair of the University of California's Comparative Immigration and Integration Program, and editor of the monthly Migration News and the quarterly Rural Migration News.


Sign Up for our E-newsletter