A New Era for Irrigation (1996) / Chapter Skim
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4 FORCES OF CHANGE AND RESPONSES
4 FORCES OF CHANGE AND RESPONSES
Pages 83-124
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From page 83... ...
Another policy was that a large portion of the available water supply would be committed to irrigation. This was not necessarily a conscious choice to favor irrigation, but it was the inevitable result of western water law, where those who were first to establish claims to use water had priority over any subsequent claimants (Bates et al., 1993~.
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From page 84... ...
The principal determinants of the profitability of irrigated agriculture are the following: · the overall state of the agricultural economy and markets, especially the benefits and costs of irrigated relative to dryland farming; · the availability of water and its cost to the farmer and to society; · available technology and management skills; · the costs of other agricultural inputs such as labor, capital, and energy; · environmental concerns and regulations; and · institutions that influence how water might be used and the opportunity costs of using water for irrigation. State of the Agricultural Economy Investments in farming depend most importantly on the state of the agricultural economy in a region and, to a lesser degree, nationally.
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From page 85... ...
Where inexpensive or subsidized surface water was not available, cheap energy and technical breakthroughs such as turbine centrifugal pumps and improved high-speed engines reduced pumping costs and contributed to the widespread use of ground water for irrigation starting in the 1950s. However, the high financial and environmental costs of developing new water supplies and the growing competition for existing supplies are critical factors affecting the future of irrigation.
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From page 86... ...
And in some areas, existing agricultural water uses are being challenged because of their impacts on water quality and fish and wildlife habitat. Institutions rl~he future of irrigation also will depend on the institutions that influence the allocation of scarce water supplies among competing uses.
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From page 87... ...
Historically, new demands have been met by developing additional water supplies through the construction of dams and interbasin conveyance facilities as well as ground water wells. Opportunities for such development increasingly are limited, primarily because financial and environmental consequences make the remaining potential sites less desirable.
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From page 88... ...
there is little economic pressure on the cost of irrigation water from federal surface sources. Ground water pumping, on the other hand, is greatly influenced by the energy costs associated with that pumping.
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From page 89... ...
FIGURE 4.2 Ground water pumping is directly influenced by the price of energy and the distance the water must be lifted from beneath the soil surface. This example shows the relationship between lift and the cost of ground water for natural gas at various prices in the Ogallala aquifer; it assumes a sprinkler irrigation system operating at 45 PSI, pump and engine efficiency of 55 percent, and distribution efficiency of 75 percent.
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From page 90... ...
The date of the water right is the date of the treaty between the tribe and the United States. In most instances, tribal water rights predate all other water users, and in the context of the prior appropriation doctrine are senior to all other users.
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From page 91... ...
Other water needs, including fisheries, wildlife, domestic, municipal, and industrial uses, usually add to the total tribal water claim. The potential size of tribal water rights claims should not be underestimated.
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From page 92... ...
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From page 94... ...
In this century, irrigated agriculture at least in most locations moved beyond its function as an agent for the settlement of the West to one of production farming. Today, irrigated agriculture is among the leading revenue-generating businesses in the western states.
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From page 95... ...
Environmental issues related to water consumption and water quality in landscape irrigation are also beginning to receive greater attention. Policymakers and regulators at the federal and state levels have begun to respond to environmental concerns about irrigation, as evidenced by various efforts to control nonpoint sources of water pollution, water policies designed to protect instream flows, continuing restrictions on the types and application of agricultural pesticides, and other measures.
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From page 96... ...
Dam construction, water diversions, and ground water pumping for irrigation and other purposes have dewatered segments of some rivers, blocked the migration of anadromous fish, changed the natural hydrographs and temperatures of rivers, and damaged or destroyed riparian habitats. Runoff from agriculture including irrigation is now considered to be one of the largest sources of water pollution in rivers, lakes, and estuaries nationwide (U.S.
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From page 97... ...
What these requirements will look like and how much flexibility irrigators will have in determining the appropriate pollution control options for their circumstances will be determined to some extent by the manner in which irrigated agriculture acts in shaping environmental policies and programs. The landscape irrigation industry also contributes to water quality and quantity problems and may face increased regulations or other constraints as water pollution control measures are debated.
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From page 98... ...
The federal reclamation system, which arose in part because many private developments went bankrupt, became important in this century and made possible the expansion of irrigated agriculture throughout the West. Maass and Anderson (1978)
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From page 99... ...
Particularly in places where the cost of water has increased measurably, irrigators are actively pursuing ways to use less water. In Texas, for example, the High Plains Underground Water Conservation District No.1 instituted a series of programs beginning in the 1950s that have reduced the depletion of the Ogallala aquifer.
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From page 100... ...
In late 1994, agricultural and urban interests holding water delivery contracts from the California State Water Project entered into the "Monterey Agreement." Among other things, this agreement will open up the marketing of State Water Project water among the contractors. Environmental concerns associated with water use also are affecting the irrigation community.
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From page 101... ...
The need to reduce or eliminate water quality degradation requires new technology to improve or maintain the water quality in both surface and ground water. Breeding has of course brought many advances, and there is hope that someday research will develop plants that use less water.
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From page 102... ...
Although promising, dramatic water savings from genetic engineering are not imminent. Therefore, for the moment, irrigation savings will need to be sought with existing crops that use water frugally and with improved efficiencies that decrease water delivery and application requirements.
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From page 103... ...
FORCES OF CHANGE AND RESPONSES 103 Genetic Engineering It is still probably too early to assess with accuracy either the potential or the limitations of genetic engineering for crop improvement (National Research Council, 1984~. Gene transfer, for example, is unlikely to have a significant effect on agricultural production practices until the late l990s.
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From page 104... ...
However, these "losses" act as a source of recharge for ground water that is used for irrigation elsewhere or that supports wetlands or other instream uses of water. On-Farm Systems Surface irrigation systems such as flood and furrow systems are still the most widely used type of system.
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From page 105... ...
The major advantage of converting to sprinkler and microirrigation systems is the ability to more effectively achieve uniform water applications. When these systems are used, less water is needed at the farm gate or from ground water sources.
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From page 106... ...
For instance, the scheduling of irrigations is a major factor in the amount of water actually supplied for crop production. If more water is applied than required, either evaporation, runoff, or drainage results.
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From page 107... ...
The economic benefits of upgrading and improving an existing irrigation system must be analyzed on a site-specific basis. Current and Future Trends A clear trend in irrigation today is the conversion of surface irrigation systems to more effective techniques such as sprinkler and microirrigation systems, especially where water costs or crop values are high.
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From page 108... ...
In areas such as the high plains of Texas with limited ground water supplies, many center pivot and LEPA sys tems are being installed. California, Florida, and Hawaii have made significant conversions to microirrigation.
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From page 109... ...
The retired lands are supposed to be those that are highly credible or that otherwise contribute to water quality problems. In 1993, more than 36 million acres of land were enrolled in this program.
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From page 110... ...
110 A NEW ERA FOR IRRIGATION ............................................................................................................................. I-rr-~-q-at-~-o-n~ -- n-st-~t-ut-~-o-n-s~ ~e-s-no-n-c ~ to u 1-a-n-q-e-:~ T. ~ new n-~-sto-~ -- -o -- g-ro-una -- wate-r -- management In !
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From page 111... ...
emerged as the supplier of onefifth of all irrigation water in the United States, the country's sixth largest generator of electric power, and manager of 45 percent of the West's surface waters (Beard, 1994~. But by the 1980s, the USER was under stress.
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From page 112... ...
Fish and Wildlife Service Regional Level Interstate Commerce Commission Various river basin commissions Great Lakes commissions Various boundary water commissions Resource conservation and development areas State Level Departments of Agriculture, Economic Development, Fish and Game, Public Safety, Health, Natural Resources, and Transportation State engineers offices Environmental quality boards Pollution control agencies Soil and water conservation boards State planning boards and agencies Water planning boards Water resources boards Tribal Level Environmental quality boards Natural resources commissions Tribal water rights offices Tribal government offices Local Level County agencies, boards, and committees Municipal agencies Township agencies Drainage districts · Emphasize the coordinated use and management of their existing facilities to improve the management of existing water and hydroelectric supplies; · Encourage conservation and improvements in the efficiency of use of already developed water and hydroelectric supplies; · Promote the sustainable use of the water and associated land resources in an environmentally sensitive manner; · Facilitate integrated water resources management on a watershed basis · Conduct the agency in a fiscally responsible manner.
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From page 113... ...
... It is too early to know just what the Bureau of Reclamation's restructuring and new mission will mean for irrigated agriculture.
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From page 114... ...
Congress excluded agriculture from point-source regulation in 1977, and, since then, implementation of the Clean Water Act has not differentiated between dryland and irrigated agriculture. But this could change in areas where irrigation is a major contributor to water quality problems.
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From page 115... ...
Today, the NRCS, along with other USDA agencies, is actively involved in providing financial, technical, and research services to farmers to conserve and protect highly credible and environmentally sensitive lands and water quality. These changes are attributed to increasing competition over water resources, environmental concerns, and concerns for safe drinking water, recreation, and other public uses.
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From page 116... ...
It offers the water right holder a choice about whether, in any given year, they would be better off renting or leasing water to another or using it themselves. It could provide water supply organizations such as irrigation districts and their water users a means of devising planned land fallowing schemes or other such approaches, similar to the arrangement involving the Palo Verde Irrigation District described above, and marketing the unused water without permanent reductions in its agricultural base or water rights holdings.
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From page 117... ...
Like the net irrigation efficiency approach, this definition acknowledges return flows, but it also explicitly accounts for the need for some portion of the water supply to leach salts out of the root zone of crops. None of these approaches to evaluating efficiency considers other related issues of the costs and benefits of the water uses that are being examined, nor do they permit consideration of the costs and benefits of making changes to increase the efficiency of use.
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From page 118... ...
Arizona is gradually reducing the allowable water duties for crops irrigated with ground water within described "active management areas" (MacDonnell and Rice, 1994~. Tribal water rights settlements involving irrigation specify project water duties, efficiencies, and systems.
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From page 119... ...
Their record to this point in serving this function, however, is mixed. Ground water overdraft is one of many examples in which flawed institutions are delaying efforts to manage water resources effectively and to plan intelligently for the future.
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From page 120... ...
They provide a vehicle for educating people about irrigation as well as for exploring ways in which agricultural needs for water can still be met while possibly providing benefits to other users. They provide a potentially important opportunity for irrigation water supply organizations to act positively in representing irrigation interests.
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From page 121... ...
Competition over developed surface water supplies occurs differently in California than in the Southeast and with different impacts (e.g., increased water prices, institutional changes, demands for new supplies)
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From page 122... ...
Washington, D.C.: Bureau of Reclamation. California State Water Resources Control Board.
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From page 123... ...
1983. Trading Conservation Investments for Water: A Proposal for the Metropolitan Water District of Southern California to Obtain Additional Colorado River Water by Financing Water Conservation Investments for the Imperial Irrigation District.
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From page 124... ...
In Symposium on Innovation in Western Water Law and Management. Boulder, Colo.: Natural Resources Law Center.
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