How much water is there in California?
How much water do California farmers use?
How do farmers get their water?
What is irrigation?
How efficiently do farmers use water?
Do farmers have to pay for water?
Is agriculture important to California’s economy?
Do some crops waste water?

How much water is there in California?
According to the Department of Water Resources, average annual statewideprecipitation is about 23 inches, corresponding to a volume of 182 million acre-feet, overthe state’s land surface. (An acre-foot is the amount of water that covers one acreto a depth of one foot, approximately 326,000 gallons.) About 65 percent of thisprecipitation is consumed through evaporation and transpiration by trees, plants and othervegetation. The remaining 35 percent comprises the state’s average annual runoff ofabout 62 million acre-feet.

How much water do California farmers use?
Of the average annual runoff of about 62 million acre-feet, not all canbe developed for urban or agricultural use. The environment uses a large portion tomaintain healthy ecosystems in our rivers, estuarine systems and wetlands. Out-of-state supplies from the Colorado and Klamath rivers bring the available surfacewater supply total to 82.5 million acre-feet. According to the Department of WaterResources, at a 2000 level of development, water in California was used as follows:

  • Environmental use: 48 percent
  • Agricultural use: 41 percent
  • Urban use: 11 percent

How do farmers get their water?
In an average year, about 30 percent of California’s agricultural applied water is provided by groundwater extraction. In drought years, when surfacewater supplies are reduced, groundwater supports an even larger percent.

Surface water supplies were developed early in the state’s history.Californians built dams, canals, pumping plants and aqueducts to carry waterto burgeoning cities and productive but dry farmland. These supplies were developedto compensate for the state’s uneven natural water distribution and to supplementavailable groundwater supplies.

The major projects that have been the primary sources of water for mostCalifornians include the federally built Central Valley Project, the State Water Projectand on the Colorado River the Colorado River Aqueduct and the All-American Canal.

Many smaller water projects have also been developed to satisfy local orregional drinking water or irrigation needs. Examples of such projects include DonPedro Reservoir, which is operated jointly by the Modesto and Turlock irrigation districtsand San Francisco’s Hetch Hetchy Reservoir and Aqueduct.

What is irrigation?
Irrigation is replacing the soil water that crop plants have used togrow. California farmers use irrigation because rainfall in a Mediterraneanclimate, such as California’s, occurs in the winter, opposite of crop needs during thesummer growing season.

How efficiently do farmers use water?
Very! Farmers in California are continually testing newtechnologies to maximize their production and economic return, and to save water!They increase their efficiency through various farm management practices, includingimproved plant varieties, laser guided leveling of land, irrigation techniques anddelivery systems designed to ensure optimum efficiency, water recycling programs and more.

Advanced irrigation technology and practices, such as buried dripsystems and deficit irrigation, have helped farmers more efficiently manage their wateruse and minimize waste.

Additionally, about one-third of California’s irrigated land is coveredunder a memorandum of understanding obligating irrigation districts to identify andimplement efficient water management practices that are cost effective.

Do farmers have to pay for water?
Yes. The cost of pumping or purchasing water from a supplier, suchas an irrigation district, is a significant cost in a farming operation. Althoughagriculture is often criticized for paying less for water than urban users, agriculturalwater does not have the same level of quality and reliability as urban water. Also,the delivery distance for agricultural water is usually shorter than for urban water andagricultural water supplies were developed earlier than many municipal supplies when costswere lower.

Is agriculture important to California’s economy?
Yes! Agriculture is one of the state’s top industries, providingone in ten jobs. In 2004 the agricultural industry contributed $32 billion to theeconomy through direct sales. When the overall economic impact is figured, theindustry is responsible for over $100 billion by creating jobs for additional products andservices such as transportation and packaging.

Ensuring a reliable, affordable supply of water for agriculture is keyto the industry’s continued economic contributions.

Do some crops waste water?
Californians are constantly reminded to conserve water. Becausethe water supply in California is so precious, certain crops are often targeted as beingwasteful of water. A crop should be evaluated on both its economic contribution andsocial value. For example, rice, alfalfa, cotton and irrigated pasture, plus the livestockand dairies they support, account for nearly one-third of all agricultural output in thestate.

Crops such as rice and alfalfa provide valuable wildlife habitat andgrowing diverse crops can be invaluable to a farmer’s overall enterprise. Differentcrops use and return different nutrients to the soil and many crops are planted inrotation to provide to the soil balance and allow the land to regenerate. Somecrops, such as grains, are less water intensive per unit of production and therefore allowa farmer to keep more land in production when less water is allocated.