All Issues

The relatively scarce ground-water resource of the Raymond Basin area of Los Angeles County has been allocated by a legal process—the Court Reference Procedure—among the wants and needs that can be satisfied by its use.

Approximately 60% of California's irrigated agriculture depends on reservoirs of ground water.

Manipulation of vegetation—as a form of management of brush covered watersheds—has shown promise as a means of increasing seasonal runoff.

Ground water generally has been physically and economically accessible to the individual overlying user. Only within the past three decades has public discussion been focused upon the potential benefits from coordinating individual development.

A water deficiency in some areas of the state, a growing population, with added irrigated acreage will increase the use and re-use of agricultural waters and tend to pollute and degrade them to the point of becoming a serious problem.

About 10% of the developed water supply in California is used for domestic or industrial purposes and 90% for crop irrigation.

With irrigation—and where necessary, with drainage—the farmer can exercise greater control over soil moisture than over any of the other soil physical factors.

One of the principal cultural practices in deciduous fruit orchards and vineyards is irrigation and its successful accomplishment frequently determines whether the grower makes a profit.

Commercial production of ornamentals—cut flowers, potted plants, nursery stock—in California has an annual wholesale value of approximately $65 million or about one half the value of the combined citrus and avocado production of the state.

Studies on the relationship between irrigation frequency and cotton yield have included various irrigation practices on a wide variety of soil types.

Rice yields have been reduced during recent years in northern California, because of cold water damage near field intake boxes.

Instruments to measure soil moisture conditions—developed as research tools—eliminate much of the guesswork in the timing of irrigations and can indicate adequate penetration for a particular soil type and crop.

The slow rate of water penetration into soils during irrigation is a serious problem, affecting—to some degree—a large portion of the major irrigated areas of California. In extreme cases there is a marked loss of production because it is difficult to supply crops with sufficient water even with frequent irrigation.

Elongation of Roots and moisture movement to roots influence the water uptake by plants.

The price farmers pay for irrigation water depends to a large extent on the cost of constructing and operating the engineering works needed to deliver the water to their farms.

Economic production of practically all crops in California is dependent on irrigation.

Methods of applying irrigation water to crops—by broad classification—are surface, subsurface and overhead or sprinkler systems.

Certain prefabricated materials used as linings in small irrigation ditches to control seepage and vegetation have shown considerable promise. Nevertheless, their use is limited—to some extent—by relatively high initial cost and questionable longevity under the variety of field conditions which exist on irrigated farms. However, increased production and availability of some of the new materials—such as plastics—are lowering costs to a point where replacement may be economical on a 1-3 year basis.

Results of recent field tests indicate the extent wind—and sprinkler and lateral spacing—influence the uniformity of water distribution from medium capacity sprinklers.

Corrosion—especially of the pitting type—of aluminum irrigation pipe has been especially severe in some areas of California.

The cost of draining farm land in the northern section of California varies with the location of the land, the ease of moving the soil, the demand for drainage in the area, and the availability of earth moving machinery, according to a recently started survey.

Pumping ground water for relief of drainage problems in agricultural lands is an established practice. However, there are many situations in California where pumping has not been used and where it might—or might not—be the solution to severe drainage problems costing farmers thousands of dollars annually in crops and soil damage.

Subsurface drainage is vital in irrigated desert areas and much research on the problem has been and is being done in the Coachella, the Imperial, and the Palo Verde valleys of California. The problems are complex, and not susceptible to simple easy solution.