Click for next page ( 126


The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement



Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.

OCR for page 125
The Irrigation Industry: Patterns of Change and Response The productivity, profitability, and sustainability of irrigation in the United States are functions of numerous interdependent variables physical, economic, political, environmental, and technological. These factors, taken alone and in combination, change over time and make the industry both diverse and dynamic. For this reason, it is impossible to depict a simple or homogeneous characteriza- tion of the irrigation industry in the United States. Although it is possible to describe the nature of irrigation and the issues with which irrigators and the industry must contend in general terms, it is more diffi- cult to generalize about the future of irrigation without looking at irrigation as practiced in different regions. Many of the key forces of change affecting irriga- tion vary in relative importance in different geographic regions. These factors also differ in relative importance between the agricultural and the turfgrass- landscape sectors of the industry. For example, while competition for water supplies and policies to protect environmental resources are issues affecting irri- gation nationwide, the specifics of water supply problems and environmental restrictions are different in the Pacific Northwest than they are in the Texas High Plains. Policy reforms within the Bureau of Reclamation will have more signifi- cance for irrigators in the western states served by that institution than for irriga- tors in the southern and eastern United States. By the same token, the predomi- nant environmental regulations affecting the turfgrass industry may not be of concern to agricultural irrigators. Within the irrigation industry, manufacturers of irrigation technologies do not face the same challenges and constraints as individuals who participate directly in irrigation activities. 125

OCR for page 125
26 A NEW ERA FOR IRRIGATION Using a simple matrix, the preceding chapter described the relationships between forces of change and responses by the irrigation industry in the United States. This construct can be used to examine and analyze the experience of irrigators and supporting institutions and to formulate an overall picture of the industry, current trends, and the future of irrigation. This chapter presents four case studies to illustrate patterns of change and response as actually observed today. These case studies demonstrate how differences in conditions of water supply, concerns over environmental protection, and economic forces bring about varied responses. These trends can help identify the most significant pressures and provide insight into the magnitude and directions of change in the industry as a whole. The case studies describe irrigation in four regions: the Great Plains, Califor- nia, the Pacific Northwest, and Florida. The cases were chosen to illustrate a variety of irrigation patterns, processes, and problems. To aid in comparing these cases, it is useful to keep in mind several attributes that affect how irrigation is practiced in a given region. These are physical patterns, cultural patterns, func- tional relations, and jurisdictional relations. Physical Characteristics. The case study regions differ in terms of cli- mate, hydrology, topography, and soils factors that dictate certain irrigation practices, technology choices, public policy, and investments. For example, irrigation in semiarid regions, including much of California and the Pacific North- west, depends on large-scale surface water delivery systems, most of which have been publicly financed and were built and operated by public agencies. Other regions, such as the Great Plains, are almost entirely dependent on privately developed ground water and have evolved pumping technologies and regional institutions to manage ground water. Humid conditions in Florida and the South- east lead to different irrigation patterns. Cultural Characteristics. Cultural characteristics also differ significantly among regions and affect choices of irrigation technologies and practices, the structure and philosophy of local and regional irrigation institutions, and re- sponses to environmental regulation and changing public policy. For example, American Indian irrigators operate in a markedly different cultural context than non-Indian irrigators, which is reflected in different philosophical, legal, and economic attributes. Individual tribes have strong spiritual values about water and land resources, values that influence their views about the political and economic value of those resources and how they are to be used. In addition, tribal resource management practices are oriented to long-term planning horizons (in contrast to the 50-year horizon commonly used by state and federal agencies). As sovereign nations, tribes have a fundamentally different relationship with federal and state agencies charged with management of water and other natural resources, and different policies and regulations pertaining to irrigation, reclamation, and crop production than non-Indian irrigation institutions organized under state laws.

OCR for page 125
THE IRRIGATION INDUSTRY 127 Another example of cultural patterns can be seen in how different regions re- spond to technological and scientific innovations. For example, in California, the agricultural sector as a whole is characterized by a high average level of irrigation efficiency, but there are marked distinctions in irrigation efficiencies between farmers in different parts of the state. Different practices can be explained in part by physical and environmental parameters the types of crops grown, soil char- acteristics, and climatic and hydrologic conditions. But some of the differences in irrigation efficiencies also are attributable to historical experience or family tradition and the irrigator's familiarity and comfort with new technologies. Finally, cultural patterns also influence irrigators' perceptions of and re- sponses to problems related to competition over water, environmental regulation, rising prices, and other factors. The types of conflicts that arise between irriga- tors and other interests, and how these conflicts are resolved, are uniquely a product of the cultural patterns that have developed over time. Functional Relations. Each irrigated area is defined by functional rela- tions as well as physical and cultural characteristics. Although some irrigators grow crops for local and regional markets, others compete in global markets. Dairies tend to locate close to urban markets. The sites of processing plants influence crops grown in some regions. Many international markets are special- ized (e.g., markets for mint from the Pacific Northwest), while other commodity markets are globally integrated (e.g., cotton and grains from the Great Plains). Some regions employ local and permanent labor, while others rely more on seasonal and immigrant workers. Crop subsidy programs target certain crops and will have a greater impact on growers in one region than another. All irrigated regions are interconnected by long distance financial markets and trade in irriga- tion equipment and supplies. These functional relations shape the economic geography of a region, just as climate and soils shape the physical geography. Jurisdictional Relations. All of the case studies depict relationships among political and administrative entities that define, to a greater or lesser extent, how irrigation develops; constraints on the availability of inputs; the context for solv- ing environmental problems; and access to information, technical assistance, and technology. The California and Florida case studies, for instance, encompass multiple state agencies as well as overlapping jurisdictions of irrigation organiza- tions and regional and local planning agencies. Additional jurisdictional levels are added in multistate cases such as the Pacific Northwest, where interstate, federal, and tribal responsibilities are considerable and policy goals are some- times in conflict. The Great Plains case represents something of an exception to this rule because interstate water management policies, for surface and ground water, are relatively undeveloped. The Pacific Northwest and California cases involve, in different ways, international treaties, policies, and organizations. American Indian water rights, issues, and jurisdictional implications cut across regions, adding the dimensions of treaty rights and U.S. obligations.

OCR for page 125
128 A NEW ERA FOR IRRIGATION The cases examined are complex. Each is a product of and distinguished by its physical, cultural, functional, and jurisdictional attributes. Each of the cases describes the character of irrigation in the region, the issues affecting irriga- tors, and how they are responding. In looking to these case studies for a picture of the future of irrigation, it is important to keep in mind that each case, while regionally or otherwise distinctive, is but a part of irrigation as a whole as prac- ticed in the United States. IRRIGATION IN THE GREAT PLAINS: TECHNOLOGICAL AND ECONOMIC CHANGES ASSOCIATED WITH DWINDLING GROUND WATER The Great Plains marks the 100th meridian, the transition between the lush green of the East and the great desert of the West. Rainfall, which comes mostly in the summer, averages about 15 to 20 inches per year (Bittinger and Green, 1980~. Precipitation varies greatly from year to year, and the area is classified as subhumid or semiarid. The climate, specifically the deficiency in rainfall, is the most significant characteristic in determining the Great Plain's environment and in making irrigation critical to the region. Irrigation in the Great Plains depends almost entirely on the water in the Ogallala formation, a large aquifer system. In much of the Ogallala, the rate of withdrawal far exceeds recharge, which means that irrigators are in effect mining the ground water aquifer. Over time, ground water overdraft results in lower well yields, lower water tables, and increased pumping costs. Thus many irrigated areas of the Great Plains will face a transition as irrigation decreases and dryland production increases in its place. This prospect has serious implications for the primarily rural communities that depend on irrigated agriculture as their eco- nomic base and for the environment as land converts to dryland production and the threat of wind-driven dust increases. The Great Plains region encompasses part or all of the states of Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, and Wyo- ming. Figure 5.1 shows the incidence of the Ogallala aquifer and its saturated thickness. Irrigation developed first in the southern region, and irrigated acres are now declining there. However, irrigated acreage is increasing in the northern part of the region. Irrigation using ground water from the Ogallala developed after World War II as a result of the introduction of the centrifugal pump. The Ogallala covers 175,000 square miles (Zwingle, 1993~. It sustains 20 percent of the irrigated acreage and provides 30 percent of all irrigation water pumped within the United States (Kromm and White, 1992b). The aquifer ranges in thickness from less than a foot to 1,300 feet, while averaging 200 feet (Zwingle, 1993~. The Ogallala contained an estimated 3 billion acre-feet of water before irri- gation began. However, the Ogallala is a confined aquifer with an average

OCR for page 125
THE IRRIGATION INDUSTRY N E BRASKA C OL OR A D O :t .. ~ ~ ~ rip 3 : NEW MEXICO lo,:: - ~ A..;' ~ ~ KANSAS ~ I. A! . - O K L AH OM A Saturate d Thickness In Feet O-~9 IoO-Igo 200~399 129 FIGURE 5.1 Saturated thickness of high plains aquifer, 1980. Source: Kromm and White, 1987.

OCR for page 125
130 A NEW ERA FOR IRRIGATION recharge rate of about 0.5 inch per year; withdrawals, on the other hand, range from 1 to 5 feet per year. Even though there is a wide range in recharge rates, especially where there are sandhills, the Ogallala is being mined with withdraw- als significantly exceeding recharge. Adjustments are already well underway to reduce water consumption. The critical issue affecting the future of irrigation in this region is the timing and types of adjustments that can be made and the effects these adjustments will have on agricultural crop production, total irrigated acre- age, future rates of ground water withdrawal, and rural development. Characteristics of Irrigation in the Great Plains il The major irrigated crops in the Great Plains are corn, wheat, grain, sor- ghum, soybeans, and cotton, with corn the dominant crop (Mapp, 1988~. There are some high-value crops such as vegetables and sugar beets, but the acreage is very limited. Over 70 percent of the total value of crop production is from irrigated acreage (Beattie, 1981). The extent of irrigated acreage in the different states of the Great Plains region is determined in large part by the incidence and characteristics of the Ogallala aquifer. Nebraska accounts for almost two-thirds (65 percent) of the annual pumping, with Texas using 12 percent, Kansas using 10 percent, Colorado using 4 percent, Oklahoma using 3.5 percent, and New Mexico, South Dakota, and Wyoming using less than 2 percent each. Over 87 percent of the aquifer is concentrated under Nebraska, Texas, and Kansas (Kromm and White, 1992b). Irrigation across the Great Plains primarily relies on surface (flood) or sprin- kler technology. Surface irrigation has moved from the open ditch and use of siphon tubes to closed delivery systems, use of shorter row lengths, and surge flow. Sprinkler systems include side roll, boom type, center pivot, traveling big gun, and linear move. In the last decade a large number of sprinkler systems replaced furrow systems, and LEPA (low-energy precision application) systems took the place of higher-pressure sprinkler systems (Bryant and Lacewell,1988~. Sprinkler-irrigated acres are increasing and by 1992 included 57 percent of all irrigated acres. Surface or flood irrigation was used on most of the remaining irrigated acres. Low-flow systems are insignificant in this region. The pattern of irrigation development in the Great Plains region since 1959 ncludes some significant variations (See Table 5.1~. The total number of irri- gated acres increased to almost 13 million in 1978 but declined by about 20 percent in the following 9 years (Kromm and White, 1992a). Figure 5.2 shows total irrigated acreage across the Great Plains from 1959 to 1987. Most of the irrigated crops in the Great Plains are enrolled in the federal farm program. The total number of acres cultivated varies among the census years according to economic and weather factors. The expansion in irrigated acreage is particularly significant in comparison to the change in nonirrigated acreage. Between 1959 and 1978 the average

OCR for page 125
131 oo oo as as as a = ~ as o En E- be oo oo be oo _ o bO ~ PI a so C) be o ~ ~ P~ ca C) _ o bO ~ P~ ca C) _ o ~ ~ P~ ca 4= ~oooo ~C~ ....... a~ , l ~o0 ~ ....... o a~a ~ _ ~_~_ ~1 + +++ ooC ~C ~o ...... C~C~ ~oo o ~o ~C~C~ a~ a~ ~0 ~0a~ a ~c~c~ o ~oo ~a~ a ~\`C,C'i oo ~a~ o~ ~o oo C~ oo 0a~ C~ C~ oo C~ a~ ~oo o ~)C~ ~4 ca ~ca s~ Z E~ 00 O ~ O ~a~ a ~oO 00 a~ C~ C~ 0000 ... a~ O ~00 00 ~O C~ ~00 00 ~C~ ca ca O ~ ~O s~ O C~ 0 44 ~ O C~ C~ C~ 00 00 00 00 o C) _1 ~_ O Z E~ C~ a~ a~ ca _1 .0 ~ 3 ~o s~ ~ o 4= a~ o o^ ~ ~ a ~ - o _1 - ca C) o ca . . z a~ a~ a~ a~ s~ 4= - C) _1 s~ bO o ca ca . . C) s~ o

OCR for page 125
32 A NEW ERA FOR IRRIGATION 14000000 1 2000000 1 0000000 8000000 6000000 4000000 2000000 o ~ _ Cl l l ~ it ~ .1 ~-1- 1 1 959 1 969 1 978 1 987 FIGURE 5.2 Total irrigated areas from the Ogallala aquifer, 1959-1987. Source: U.S. Census of Agriculture (Kromm and White, 1992a, p. 24~. proportion of cropland under irrigation rose relative to nonirrigated acreage for the Ogallala in part of all six states. In Nebraska the proportion of irrigated acreage rose from about 28 percent in 1959 to almost 50 percent in 1987. From 1978 to 1987 the proportion of cultivated land irrigated in the Ogallala aquifer region declined in Texas and Kansas, increased in Nebraska and Colorado, and was about the same for Oklahoma and New Mexico (Kromm and White, 1992a). The expansion in irrigated acres since the 1950s occurred with increased pumping of ground water. Ground water supplies will be the limiting factor in the development and distribution of irrigation for this region in the future. In 1978, some 12.9 million acres in the Great Plains region were irrigated with ground water. Projections for the year 2020 indicate that 5.4 million irrigated acres will revert to dryland farming or be abandoned (Banks et al., 1984~. The areas where withdrawals can be expected to have the greatest impact by 2020 and beyond are New Mexico, Oklahoma, and Texas. These states account for over 3 million irrigated acres. Projections for Kansas and Texas show substantial de- creases in irrigated acreage and corresponding increases in dryland acreage. Irri- gated acreage in Colorado and New Mexico was projected to decrease without an

OCR for page 125
THE IRRIGATION INDUSTRY 133 accompanying increase in dryland acreage (Stewart and Harman, 1984~. Ne- braska is expected to continue to use 1.9 billion acre-feet of Ogallala water because of areas of substantial recharge and to be irrigating 11.9 million acres (Reisner, 1993~. If these projections prove true, irrigated acreage in the Great Plains in 2020 and beyond will exceed current levels. However, the geographical distribution of irrigated lands will shift to northern states as southern areas adjust from full irrigation to supplemental irrigation to dryland production. As ground water supplies continue to dwindle, particularly in the southern part of the Ogallala aquifer region, the transition to dryland will increase vulner- ability to soil erosion from wind. The seriousness of wind erosion is shown by the 9 million acres enrolled in the Conservation Reserve Program (CRP) from the Great Plains. Erodible lands have been a priority since the 1930s dustbowl era, and under the CRP of the Department of Agriculture farmers receive payments to idle cropland and establish grass and other cover to reduce erosion. If the CRP is continued and gives priority on wind erosion control, it could be important in controlling wind erosion. Forces of Change and Responses In the Great Plains, as with the West generally, irrigation is most acutely affected by the rising cost of water. Agriculture, which accounts for about 88 percent of western water consumption, is not only the largest but also the mar- ginal user of western water (Frederick and Hanson, 1982~. Thus, as water sup- plies become more scarce, higher water costs threaten the continued expansion of irrigation as well as the continued production and profitability of current irriga- tors. In addition to ground water depletion and higher pumping costs, environ- mental concerns are putting more emphasis on water quality. These factors will play a significant role in determining the future of irrigation in the Great Plains, where some of the impacts and responses by farmers already are apparent. Farmers over the Ogallala aquifer have been pumping water at a rate that exceeds recharge by severalfold (12 to 40 times more is pumped than is re- charged). With recharge essentially negligible in most areas, continued mining of the aquifer will continue to reduce water availability, reduce well yields, and increase pumping lifts. The impacts of increasing ground water depletion can be seen in the Texas High Plains, where annual pumping rates range from 5 to 8 million acre-feet, depending on prices and rainfall patterns (Lacewell and Lee, 1988~. Continued pumping will result in a further decline of the water level in the Ogallala. A study done in the 1980s projected that the declining water table would support only about 55 percent of the 1980 irrigated acreage by the year 2000 and only 35 to 40 percent by 2030 (High Plains Associates, 1982~. This same study for the six-state region forecasts that by 2020, water levels in the Ogallala will decline by 23 percent, with Texas having used two-thirds of its supply. At the same time,

OCR for page 125
134 il A NEW ERA FOR IRRIGATION ncreasing lift and relatively expensive energy can be expected to maintain an upward pressure on the cost to pump. From the early 1970s to 1985, costs increased approximately 400 percent (Ellis et al., 1985~. Widespread water quality concerns have emerged with the development of irrigated agriculture in the Great Plains. A recent evaluation of the status of water quality and agriculture for the region (Lacewell et al., 1992) concluded that irrigated agriculture and confined livestock operations are the principal factors related to water quality problems across the Great Plains. Agricultural runoff is identified as the most extensive source of surface water quality degradation, accounting for about 60 to 80 percent of the water quality problems in the Great Plains. Soil erosion contributes to pollution through the combined effects of turbidity, siltation, and loading of nutrients adsorbed to the soil particles. Erosion in the Great Plains is dominated by wind action, which probably has a greater impact on soil fertility than off-site water quality. A major source of ground water contamination is agricultural nutrients and pesticides. Ground water contamination by nutrients or pesticides has been docu- mented in every state of the region except Wyoming, where contamination is suspected (U.S. Department of Agriculture, 1989~. Of these contaminants, nitro- gen fertilizers play a leading role because nitrates not used by plants are leached into the ground. One means for significantly reducing this pollution may be through the controlled application of water through fertilization and irrigation scheduling or "chemigation" (Kromm and White, 1992b). Another nonpoint source of water contamination related to irrigation is run- off of pesticides and fertilizers into rivers, streams, and lakes. Across the Great Plains, farmers typically capture and concentrate runoff from irrigated fields in runoff pits, ponds, or playa lakes. Many farmers recirculate the water back through the irrigation system. Nevertheless, some runoff makes its way to other surface sources, and nutrients and some pesticides held in ponded water may lead to ground water contamination over the long term. A final cause of water impair- ment in the Great Plains is salinity. The relationship of salinity to other waste discharges is basically additive. Current policies regarding agricultural nonpoint-source pollution encourage voluntary adoption of farming practices designed to protect surface water and ground water resources from agricultural chemicals and sediment. A major issue regarding policies directed to water quality in the Great Plains is the effectiveness of voluntary programs. Without significant improvements in water quality, there will be increasing pressure to adopt a regulatory approach to address agricultural nonpoint-pollution problems in the Great Plains and other irrigated regions of the United States (Lacewell et al., 1992~. The Ogallala experience shows that conventional farming with excessive water use cannot succeed over a long period of time and that adjustments toward more self-sufficient systems are needed. Some self-correcting mechanisms al- ready exist that ensure that a given farming operation will require less water from

OCR for page 125
THE IRRIGATION INDUSTRY 135 the Ogallala each year. Because of higher pumping costs and lower well yields, farmers make adjustments in their farming organization, including the mix of inputs and equipment used. Farmers no longer feel that maximizing yield per acre is the most important goal; instead they have begun to concentrate on achiev- ing an economically effective use of irrigation water. In the past decade, there have been adjustments in technology and agricultural practices, institutions, and rules and regulations. These adjustments have occurred at the farm level as well as at the regional level (Zwingle, 1993~. Conservation Perhaps the most uncontroversial course of action for the Ogallala region is to conserve water primarily by increasing irrigation efficiency. As water costs rise, technologies and management practices that conserve both energy and water become more cost-effective and often essential to the continued profitability of irrigated farming. In general, farmers in the Great Plains have a wide range of choices for responding to high energy and water costs before abandoning irrigation. These opportunities include improving pumping efficiency, installing tailwater reuse systems, reducing a sprinkler's operating pressure, institutions' irrigation sched- uling, improving conveyance efficiency, monitoring soil moisture, shaping and leveling the land, irrigating alternate furrows, growing crops with lower water requirements or higher returns to water, and reducing the quantity of water deliv- ered to a given crop. Other adjustments to increase irrigation efficiency include shortening row lengths for gravity-flow systems, converting to low-pressure sprin- klers, and replacing worn sprinkler nozzles (Ellis et al., 1985~. Improved farming systems also contribute to Ogallala water conservation. Minimum tillage, rotating a row crop such as cotton or sorghum with wheat or other small grains, and careful use of herbicides for weed control to reduce the number of implement trips across the fields can cut costs and maximize the use of pumped and natural water. Another improved management practice is the lim- ited irrigation-dryland system, in which the upper half of a field is fully irrigated, the next one-quarter is a tailwater runoff section using runoff from the fully irrigated section, and the lower quarter is managed as a dryland section solely dependent on rainfall. Throughout the Great Plains, this system offers a higher water use efficiency than full or conventional irrigation (Gilley and Fereres- Castiel, 1983~. Technologies for improving efficiency of water use in irrigation have made dramatic advances in recent years (Council for Agricultural Science and Technol- ogy, 1988~. Improved management options for the effective use of irrigation water have become available through advances in irrigation equipment and have significant implications for the future of irrigation from the Ogallala. For ex- ample, advances in sprinkler systems include reducing the pressure to deliver

OCR for page 125
158 A NEW ERA FOR IRRIGATION The Northwest Power Planning Council a regional organization made up of representatives of the four states, develops Power Plans and Fish and Wildlife Programs for the Columbia River basin. In 1991 the council, in response to potential listing of endangered species and in response to a request of the gover- nors of the four states following the Salmon Summit, embarked on a salmon rebuilding program. The position of the council is that those who use the river should bear their share of the costs of measures needed to rebuild fish stocks. Although the council does not play a direct role in shaping the future of irrigation, it has incorporated in its Fish and Wildlife Program actions that will have an impact on agricultural irrigation. The NPPC has approved several actions intended to assist in the recovery of the Snake River salmon runs. These actions, which are being implemented by the Bureau of Reclamation and the states, include limited future water withdrawals, flow augmentation, water acquisition, new storage assessment, and uncontracted storage space. These significant actions affect and involve the irrigation commu- nity in all four states, but especially in Idaho, Oregon, and Washington. For example, in the Snake River basin a report prepared for the Northwest Power Planning Council and the Bonneville Power Administration has identified water management opportunities in Oregon and Idaho to secure at least one million acre-feet of water per year for the Snake River basin. The findings and conclu- sions of the study show that by using water use efficiencies, market mechanisms, water transactions, and land fallowing and implementing on-farm management and conservation measures, at least one million acre-feet of water can be acquired annually from existing uses, although no water acquisition has occurred yet. At the individual state level, Oregon and Washington embarked on an effort to restrict water withdrawals from the Columbia and Snake rivers and their tribu- taries, following the listing of the Snake River sockeye. This restrictive policy, coupled with an aggressive instream flow program, places most agricultural wa- ter users in the position of having to become more efficient with their existing water use. At the local level, watershed management and regional planning programs involving irrigation districts and individuals are working to improve water qual- ity and quantity and to identify and carry out irrigation water management im- provements on the ground. The states of Washington and Oregon have provided grants and loans to help these efforts. In addition, irrigation and hydropower users and environmental and tribal representatives are participating in local efforts to design solutions to water man- agement problems. Incentive-based conservation programs are being imple- mented throughout the region to encourage conservation, reallocation, and water acquisition. In Oregon a new organization, "The Oregon Water Trust," patterned after the Nature Conservancy, was formed for the purpose of purchasing water mostly from irrigators for instream uses. The irrigation community is playing an important role in defining and implementing the trust. In the Deschutes Basin,

OCR for page 125
THE IRRIGATION INDUSTRY 159 the Environmental Defense Fund, the Confederated Tribes of the Warm Springs Reservation of Oregon, and the irrigation districts have entered into a contract with the Bureau of Reclamation for a demonstration project to implement water conservation and secure conserved water and to review the institutional con- straints and propose changes to make water leasing projects more effective. The Umatilla example is another illustration that fish enhancement and irri- gation can be compatible. The Umatilla River is a tributary of the Columbia River that drains farmland and parts of the Umatilla Indian Reservation in north- east Oregon. Irrigation diversions had dried up the river for over 20 years, and its salmon runs were history. Broad political support was built for a comprehensive restoration project. The Umatilla Tribes, Oregon fish and wildlife agencies, and the irrigators have restored some fish runs and are working to restore flows to the lower river and keep the farm economy whole. The irrigation water now taken from the Umatilla will be replaced by water pumped from the Lower Columbia River. Although there are cooperative efforts underway to recover fish populations, and some local successes, the enormous scope of the salmon recovery effort, traditional water management policies and politics, the inadequacy of the existing institutions, and the multitude of competing interests are major constraints. Conclusion The future of irrigation in the Pacific Northwest is closely related to the future of the Columbia River. The decision to recover salmon in the Northwest involves trade-offs and will require broad cooperation. Opportunities and tools exist to address the needs of the salmon and steelhead but not without costs. How significantly agricultural irrigation will be affected is going to depend on its willingness to participate and contribute to the enormous effort of rebuilding the salmon populations. Although today there is no consensus on how the conflicts and changes should be resolved, there is more of an awareness of the limits that individual state, tribal, and federal governments have in resolving these highly complex and controversial conflicts. It is obvious that accommodation of the many demands cannot be done without using a comprehensive ecosystem approach and unprec- edented legal and institutional collaboration among the multiusers, multiinterests, and multijurisdictions. Like the Columbia River itself, the challenge of providing water and other measures to protect salmon binds together all water users in the basin. In this context, it is stakeholders who develop more effective means to resolve conflicts, develop consensus, provide flexibility to respond to changing needs, improve the efficiency of water for irrigation, and optimize the allocation of water resources. Full public participation must be sought, and economic and social impacts must be considered.

OCR for page 125
160 A NEW ERA FOR IRRIGATION IRRIGATED AGRICULTURE IN FLORIDA: INSTITUTIONS AND INDUSTRY IN TRANSITION Unlike most areas dependent on irrigation, annual rainfall in Florida consis- tently exceeds evapotranspiration. Nevertheless, irrigation is required by the marked seasonality of rainfall in Florida. The ability to apply supplemental water during the dry spring months is essential to produce agricultural crops and to maintain urban landscapes. As with many states in the arid West, the competition for water, expanding environmental constraints, and rapidly changing market conditions are major factors influencing irrigation in the Southeast. In addition, differences in climate, natural environment, soils, and prevailing cropping patterns create distinct chal- lenges for the management of irrigation systems in Florida (Camp et al., 1990~. Irrigation in Florida provides a hedge against droughts and freezes, and it is an important element in achieving optimal yields. Reliable irrigation allows farmers to produce high-value crops and to meet market windows that are closed to other parts of the country because of climate. Reliance on ground water is the rule for the majority of Florida agriculture. In spite of high annual rainfall, surface supplies are the primary irrigation source only in the region adjacent to Lake Okeechobee, which includes Florida's sugarcane acreage and important amounts of vegetables, citrus, and sod. Characteristics of Irrigation in Florida In 1950, irrigated cropland in Florida was estimated at 300,000 acres. Fol- lowing the droughts of the early 1960s, irrigated acreage jumped to over one million acres. By 1978 the irrigated area had climbed to over 2 million acres, only to drop by 400,000 acres because of freezes in the 1980s. Withdrawals totaled 3.8 million gallons per day, of which 53 percent was ground water and 47 percent was surface water. Agricultural expansion over the next decade raised the irrigated area to 2.1 million acres by 1992. Agriculture was the largest user of water in Florida in 1990 (Marella,1992~. Citrus crops account for the largest acreage and withdrawals for irrigation (33 percent). Other crops with significant water use are sugarcane (22 percent), sod (5 percent), and turfgrass on golf courses (5 percent) (Marella, 1992~. The 1987 Census of Agriculture ranked Florida fourth nationally in market value of agricul- tural products sold from irrigated farms ($3.3 billion). In 1990, Florida had the largest irrigation withdrawals of any state east of the Mississippi River (Marella, 1992~. Florida applies more irrigation water per acre than does Texas, even though rainfall in Florida far exceeds that in Texas (Bajwa, 1985~. Since 1972, Florida has been governed by one of the most progressive water resource management statutes in the country. In response to one of the worst droughts in the state's history in 1971, and public concern about the need for

OCR for page 125
THE IRRIGATION INDUSTRY 161 oversight of water resource management in the face of rapid population growth, the state created five regional Water Management Districts (WMDs). These agencies have the legal authority and financial capacity to manage water compre- hensively through regulation of all water use and surface water management, setting criteria for water quality and wetland protection, and imposing conserva- tion and water shortage management. They also have evolved into the largest landowners in the state through well-funded land acquisition programs designed to preserve Florida' s environmental and water-related resources. Water in Florida belongs to the people collectively and can only be used according to administrative and resource protection criteria set by the WMDs. The license to use water is a temporary benefit that is reevaluated every 5 to 10 years. This exposes large irrigation users to possible reallocation to other con- sumptive uses, such as potable supply for cities. It also provides flexibility for changing social and political values, such as wetland protection, and allows the WMDs to mandate the adoption of the most efficient irrigation technology where that is warranted. The WMDs began as water resource agencies dedicated to water supply and flood control. They have evolved into powerful and well-financed entities domi- nated by environmental protection and land acquisition and management man- dates in addition to their traditional water resource roles. The comprehensive legal framework enacted in 1972 has allowed the WMDs to preside over an orderly allocation process as the state's abundant water was made available to fuel agricultural and urban growth. Now they are facing the prospect of having to tell some potential users "no," and even some existing users "no more." This process will not be nearly as orderly as the initial exercise of their authority. The institution itself is under pressure to a degree it has never been in the past. It is too early to tell which issue will dominate in the next evolutionary phase of water management in Florida, but water supply is clearly the issue that will focus the spotlight on the Water Management Districts. Forces of Change and Responses Despite averaging over 50 inches of rain per year, Florida is facing chal- lenges to the use of water for irrigation that are strikingly similar to those in California, namely, growing environmental and urban demands for water. The urban population is growing steadily and is finding its traditional water sources no longer sufficient. Florida's population has doubled in the past 20 years and is slated to reach 16 million by the year 2000. This growth is an unrelenting challenge to water management that is testing the state's institutional capacity to balance the competing demands on the natural resources. In addition, the people of Florida are beginning to question some of the environmental trade-offs that past generations were willing to make to encourage economic development. In a state dominated by urban population centers, the lack of understanding and ac

OCR for page 125
162 A NEW ERA FOR IRRIGATION ceptance of the value of agriculture poses a constant challenge to the irrigation industry. Environmental Issues The extraordinary commitment that Florida has made to irrigated agriculture has resulted in significant impacts to water-related environmental resources. Water levels in many lakes in central Florida are falling and require augmentation from wells to maintain surface levels. Wetlands adjacent to some irrigated lands are being degraded, if not completely eliminated. Water quality problems from agriculture are caused not by return flows as is the case in the West, but by stormwater runoff. Runoff from sugarcane and vegetable production in the Ever- glades Agricultural Area (EAA) is a leading concern of government agencies charged with the protection of the Everglades ecosystem. Even in areas where irrigation water supplies have not been limiting, concern over contaminants in runoff, especially nutrients, is leading to a reduction in farm acreage. The large-scale environmental systems, which include not only the Ever- glades, but also the many estuarine areas that evolved under water-rich condi- tions, have become a dominant force in the debate over future water use. The goal of ecosystem restoration has become a direct limit on new water use in adjacent areas and is also being debated by government, industry, and environ- mental groups considering reallocation of water from existing uses to the environ- ment. One of the most critical and controversial environmental issues in Florida centers on the nutrient enrichment of portions of the Everglades by stormwater runoff from the sugarcane and vegetable fields south of Lake Okeechobee. In the 1960s, some 500,000 acres of sawgrass prairie were transformed into the Ever- glades Agricultural Area by the federally authorized and constructed Central and Southern Florida Project. Currently, there are approximately 425,000 acres in sugarcane, 32,500 acres in vegetables, 12,000 acres in rice, and 25,000 acres in sod production. Vegetable farmers grow multiple crops, so the actual vegetable acreage harvested is closer to 70,000 acres. Most farms within the EAA are large, encompassing thousands of acres. Irrigation and drainage are provided by an on- farm network of canals connected to the federal Central and Southern Florida Project. The Everglades evolved 5,000 years ago as an oligotropic (very low in nutrients) system. Today, stormwater runoff from the EAA is pumped directly into the remaining undeveloped Everglades. The water, while very low in phos- phorus compared to other agricultural or urban runoff, contains phosphorus con- centrations about 15 times the background levels of the marsh (150 versus 10 parts per billion). The runoff coming from the EAA is considered one of the contributing factors in the expansion of dense cattail growth into native sawgrass prairie systems.

OCR for page 125
THE IRRIGATION INDUSTRY 163 The controversy over water quality problems in the Everglades spawned 5 years of bitter litigation between cane and vegetable growers and state and fed- eral agencies. In 1994 the state passed special legislation outlining an interim approach to the problem the construction over the next decade of 40,000 acres of artificial marshes to act as nutrient filters for the runoff. The cost to farmers is expected to be between $200 and $320 million over the next 20 years, and 25,000 acres will be removed from production. Federal resource agencies are in the early stages of considering proposals to remove another 100,000 acres of the most productive land from production in the next 10 years. This approach to solving the water quality problems of the Everglades has come with another significant cost. The years of expensive litigation have reduced the potential for collaborative efforts between the government, agriculture, and environmental groups. A case with far less controversy centers on the expansion of citrus produc- tion into southwest Florida. Florida was hit in the early 1980s by a series of freezes that severely damaged production in the historic citrus belt in the center of the state. Since that time, citrus production has been moving south to avoid frost damage. Citrus acreage south of Lake Okeechobee has doubled in the past 10 years to 148,000 acres. Permitting for new groves continues, and the total irrigated area could climb another 50,000 acres by the year 2000 (Mazotti et al., 1992), although weakened market conditions may delay this process. Historically, the southwest Florida citrus area consisted of wetlands (61 percent) and uplands (39 percent) dominated by pine flatwoods. By 1973, some 36 percent of the total area had been converted to agricultural use, first to pasture and then to crops and citrus. Today, 60 percent of the freshwater marshes and 88 percent of the pinelands have been lost. Although citrus groves do not necessar- ily eliminate biological diversity (Mazotti et al., 1992), the linkage between uplands and wetlands is critical to maintaining biological integrity. The frag- mented remnant flatwoods are critical habitat for more wildlife species than any other cover type and are vulnerable to further development. In response to the continuing loss of temporary wetlands, and the loss or fragmentation of forest and range habitats, the South Florida WMD is developing new rules to require a thorough evaluation of every new and existing water use to eliminate any detrimental effects on wetlands. Federal agencies are also requir- ing endangered species reviews on all major changes in upland areas. The citrus industry has responded quickly to these changes. Citrus farmers have been pioneers in the development of new technology for water conservation, and they have worked with regulatory agencies to find ways to preserve many habitat values. While they are certainly not immune from the environmental and com- petitive forces facing agriculture, they have not been confronted with the intense pressures facing farmers in the Everglades.

OCR for page 125
164 Water Supply Issues A NEW ERA FOR IRRIGATION In Florida, water conservation has become a necessity. In some areas, avail- able supplies are limited by subsurface salt water intrusion; in other areas, sup- plies are limited by competing needs of nearby wetlands. There has been an aggressive initiative by agribusiness to develop the most efficient irrigation sys- tems possible. There has also been an equally determined program by govern- ment institutions to encourage and, in some areas, mandate such technology shifts. In the mid-1980s, there was considerable focus on increasing irrigation as- . Decency. Of the more than 4.6 million acres of commercial agricultural land in Florida, over 2 million acres (44 percent) are irrigated (Smajstrla et al., 1993~. Farmers have begun to adopt more efficient irrigation technologies, including microirrigation. Currently, 418,000 acres are irrigated with microirrigation systems, and almost 94 percent of these acres are in fruit crops, primarily citrus. Approximately 50 percent of the current 2 million acres are adaptable and may be expected to convert to microirrigation. The rate of conversion is estimated to be about 31,000 acres per year, with most of this occurring in fruit and vegetable crops (Smajstrla et al., 1993~. In Orlando, 23 million gallons per day of reclaimed water is now being distributed to citrus groves for irrigation. The water, which has to meet rigorous water quality standards, is being used on 21 grove sites through 29 miles of pressurized distribution lines. To help meet the demands for citrus and turfgrass irrigation, and address the increased competition for water use, reclaimed waste- water for irrigation has increased from zero in 1970 to 51 million gallons per day in 1985 and to 170 in 1990. The significance of water supply issues, specifically the competition be- tween urban and agricultural water uses, can be seen in the example of the Tampa Bay region. In 1989, agricultural water use accounted for 64 percent of the total ground water withdrawn in the Floridan aquifer, the area's primary source of water, west and south of Tampa Bay. Citrus, tomatoes, and other vegetables make up the largest irrigated acreage in the area. Except for relatively short-term fluctuations caused by freezes, total citrus acreage has remained fairly constant at about 260,000 acres since the 1960s. Continued use of the aquifer would result in salt water intrusion, permanent decline in lake levels, and the loss of wetlands. The water level in one of the most severely affected lakes has dropped 14 feet in the past 10 years. Over 90 lakes in the area require well water augmentation to maintain water levels (Bajwa,1985~. Test wells in Hillsborough and Sarasota counties have doubled in chloride con- tent to 1,900 and 1,400 milligrams per liter, respectively. In response to these problems, the Southwest Florida WMD has stopped issuing new permits for ground water withdrawals until regulations requiring increased water use effi- ciency for all users can be implemented. Water-conserving technologies will be required for both new and existing users. Agricultural water use permits will be

OCR for page 125
THE IRRIGATION INDUSTRY 165 based on system efficiency, crop efficiency, and irrigation management (South- west Florida Water Management District, 1993~. The citrus industry, which has already installed microirrigation technology, is not expected to be affected. To- mato, melon, and potato farmers are expected to convert to fully enclosed seep- age techniques or add drip irrigation. A preliminary economic analysis commissioned by the Southwest Florida WMD found that the plan is not expected to significantly reduce the agricultural economy in terms of sales and employment through the year 2015. However, irrigators will be required to finance new water conservation technologies, which will lower business earnings. If growers maintain existing irrigation system efficiencies, total acreage in production will decline. Sod production is expected to shift to sprinkler systems to increase irrigation efficiency. Conclusion Although national statistics on the importance of irrigation are dominated by western states, Florida is ranked tenth in total irrigated acreage (2.1 million acres) and fourth in market value of irrigated crops harvested ($3.3 billion). Irrigated agriculture in Florida has grown substantially in the past decade and is projected to grow significantly over the next 30 years. Irrigation in the region relies heavily on ground water even though surface waters are extensive. Competition for water is becoming intense, as is the pressure on irrigated agriculture from environmental regulation of water and land use. Tight restric- tions on impacts to wetlands, and the desire to restore many previously disturbed natural systems, could severely limit future growth of irrigated agriculture, and in some cases may significantly reduce the number of acres in production. Agricul- ture has responded to these pressures with a more scientific approach to water use and wholesale conversion to new technology and management techniques. In some cases, though, the debate has included litigation, media warfare, and politi- cal skirmishing by both government and agriculture. In a few instances, pressure on agriculture has led to business failures and community hardship. The institu- tions that manage water have also changed, in some cases to try to solve these water problems through research and cost-sharing programs, and in others to use their regulatory power to force change on the irrigation industry. With changes in the demographic composition of the state, and related changes in political leadership, traditional alliances and public support for agri- culture are weakening. It will take years to rebuild the trust between agriculture and the government in the Everglades region. On the other hand, the long history of the citrus industry and the fact that it is not centered in or near the Everglades have nurtured a cooperative relationship between that industry and the govern- ment, one that is likely to endure. Ultimately, the future of irrigated agriculture in Florida will not be limited by the supply of water. It will depend on the ability of agriculture, urban water uses, and environmental interests to commit to a collabo

OCR for page 125
166 A NEW ERA FOR IRRIGATION rative process of achieving mutually acceptable solutions to the state's water resource challenges. Recent experience indicates that when problems are ad- dressed at the local level, with all stakeholders participating, lasting solutions are possible. REFERENCES American Fisheries Society. 1991. Pacific Salmon at the Crossroads: Stocks at Risk from Califor- nia, Oregon, Idaho, and Washington, Vol. 16, No. 2, March-April. J. E. Williams and J. A. Lichatowich, eds. Bajwa, R. S. 1985. Analysis of lfrigation Potential in the Southeast: Florida, A Special Report. Natural Resource Economics Division, Economic Research Service ERS Staff Report No. AGE851021. Washington, D.C.: U.S. Department of Agriculture, P. 42. Banks, H. O., J. O. Williams, and J. B. Harris. 1984. Developing new water supplies. In Water Scarcity: Impacts on Western Agriculture. E. A. Englebert and A. F. Scheuring, eds. Berkeley: University of California Press. Pp. 109-126. Beattie, B. R. 1981. Irrigated agriculture and the problems and policy alternatives. Western Journal of Agricultural Economics 7 (December 1981):289-299. Bittinger, M. W., and E. B. Green. 1980. You Never Miss the Water Till. . . (The Ogallala Story). Resource Consultants, Inc. Littleton, Colo.: Water Resources Publication. Bonneville Power Administration. 1993. Modified Stream Flows, 1990 Level of Irrigation, Colum- bia River and Coastal Basins, 1928-1989. Portland, Oregon: Bonneville Power Administration. Bonneville Power Administration, U.S. Corps of Engineers, and U.S. Bureau of Reclamation. 1994. Columbia River System Operation Review, Draft Environmental Impact Statement and various appendices. Portland, Oregon: Columbia River System Operation Review Task Force. Bryant, K. J., and R. D. Lacewell. 1988. Adoption of Sprinkler Irrigation on the Texas High Plains: 1958 to 1984. Department of Agricultural Economics, Texas Agricultural Experiment Station, Department Information Report DIR 88-1. College Station, Tex.: Texas A&M University. California Department of Water Resources. 1994. California Water Plan Update. Bulletin 160-93. Sacramento, Calif.: Department of Water Resources. Camp, C. R., E. J. Sadler, R. E. Sneed, J. E. Hook, and S. Ligetvari. 1990. Irrigation for humid areas. In Management of Farm Irrigation Systems. G. J. Hoffman, T. A. Howell, and K. H. Solomon, eds. St. Joseph, Mich.: American Society of Agricultural Engineers. Pp. 551-578. Checcio, E., and B. Colby. 1993. Indian Water Rights: Negotiating the Future. Water Resources Research Center, University of Arizona. Council for Agricultural Science and Technology (CAST). 1988. Effective Use of Water in Irri- gated Agriculture. Report No. 113. Demment, M. W., K. G. Cassman, W. J. Chancellor, E. W. Learn, R. S. Loomis, D. N. Manns, D. R. Nielsen, J. N. Seiber, and F. G. Zalom. 1993. California Farming System: Diversity to Compete in a Changing World. Agriculture Issues Center. Davis, Calif.: University of California. Ellis, J. R., R. D. Lacewell, and D. R. Reneau. 1985. Economic Implications of Water-Related Technologies for Agriculture: Texas High Plains. Texas Agricultural Experiment Station MP- 1577. College Station, Tex.: Texas A&M University. Frederick, K. D., and J. C. Hanson. 1982. Water for Western Agriculture. Washington, D.C.: Resources for the Future. Gilley, J. R., and E. Fereres-Castiel. 1983. Efficient use of water on the farm. OTA commissioned paper, excerpted in Water Related Technologies for Sustainable Agriculture in U.S. Arid/Semi- arid Lands. OTA-F-212. Washington, D.C.: U.S. Congress, Office of Technology Assessment. Great Plains Agricultural Council, Water Quality Task Force. 1992. Agriculture and Water Quality

OCR for page 125
THE IRRIGATION INDUSTRY 167 in the Great Plains: Status and Recommendations. Publication No. 140. College Station, Tex: Texas Agricultural Experiment Station. High Plains Associates. 1982. Six-State High Plains-Ogallala Aquifer Regional Resources Study. Report to the U.S. Department of Commerce and the High Plains Study Council. Austin, Tex.: High Plains Associates. Idaho Agricultural Statistics Service. 1992. Idaho Agricultural Statistics. Boise: Idaho Statistical Reporting Service. Kromm, D. E., and S. E. White. 1987. Interstate groundwater management preference differences: The Ogallala region. Journal of Geography 86(1):5-11. Kromm, D. E., and S. E. White. 1992a. Groundwater problems. In Groundwater Exploitation in the High Plains, D. E. Kromm and S. E. White, eds. Lawrence, Kans.: University Press of Kansas. Pp. 1-27. Kromm, D. E., and S. E. White. 1992b. The High Plains Ogallala region. In Groundwater Exploita- tion in the High Plains, D. E. Kromm and S. E. White, eds. Lawrence, Kans.: University Press of Kansas. Pp. 44-63. Lacewell, R. D., and J. G. Lee. 1988. Land and water management issues: Texas High Plains. In Water and Arid Lands of the Western United States, A World Resources Institute Book. M. T. El-Ashry and D. C. Gibbons, eds., Cambridge and New York: Cambridge University Press. Pp. 124-167. Lacewell, R. D., and E. Segarra. 1993. Farmers', Lenders' and Water Districts' Response to Texas Low Interest Loan Program for Water Conservation in Agriculture. Texas Water Resources Institute. TR-164. College Station, Tex.: Texas Agricultural Experiment Station, Texas A&M University. Lacewell, R. D., J. R. Ellis, and R. C. Griffin. 1985. Economic efficiency implications of changing groundwater use patterns. In Issues in Groundwater Management, E. T. Smerdon and W. R. Jordan, eds. Austin, Tex.: University of Texas, Center for Research in Water Resources. Lee, J. G. 1987. Risk implications of the transition to dryland agricultural production on the Texas High Plains. Doctoral thesis, Texas A&M University, College Station. Mapp, H. P. 1988. Irrigated agriculture on the High Plains: An uncertain future. Western Journal of Agricultural Economics 13:339-347. Marella, R. L. 1992. Water Withdrawals, Use and Trends in Florida, 1990. U.S. Geological Survey, Water-Resources Investigations Report 92-4140. Tallahassee, Fla. P. 38. Mazotti, F. E., L. A. Brandt, L. G. Pearlstrine, W. M. Kitchens, T. A. Obreza, F. C. Depkin, N. E. Morris, and C. E. Arnold. 1992. An Evaluation of the Regional Effects of New Citrus Develop- ment of the Ecological Integrity of Wildlife Resources in Southwest Florida. West Palm Beach, Fla.: Southwest Florida Water Management District. Moore, M. R., W. M. Crosswhite, and J. E. Hostetler. 1987. Agricultural Water Use in the U.S. 1950-1985. In National Water Summary 1987 - Hydrological Events and Water Supply and Use: USGS Water-Supply Paper 2350. J. E. Carr, E. B. Chase, R. W. Poulson, and D. W. Moody, compilers. Reston, Va.: U.S. Geological Survey. National Research Council. 1989. Irrigation-Induced Water Quality Problems. Washington, D.C.: National Academy Press. Northwest Power Planning Council. 1994. Columbia River Basin Fish and Wildlife Program. Portland, Oregon: Northwest Power Planning Council. Opie, J. 1993. Ogallala: Water for a Dry Land. Lincoln, Neb.: University of Nebraska Press. Reisner, M. 1993. Cadillac Desert. New York: Penguin Books. Rosenberg, H. R., R. E. Garrett, R. E. Voss, and D. L. Mitchell. 1993. Labor and competitive agriculture technology in 1990-2010. In On the Brink of a New Millenium. Oakland: University of California, Agriculture Issues Center. Smajstrla, A. G., W. G. Boggess, B. J. Boman, G. A. Clark, D. Z. Haman, T. A. Obreza, L. R. Parsons, F. M. Rhoads, T. Yeager, and F. S. Zazueta. 1993. Microirrigation in Florida: Sys

OCR for page 125
168 A NEW ERA FOR IRRIGATION tems, Acreage and Costs. Bulletin 276. Florida Cooperative Extension Service, University of Florida. P. 12. Southwest Florida Water Management District. 1993. Southern Water Use Caution Area Manage- ment Plan. Draft 9-01-93. West Palm Beach, Fla: Southwest Florida Water Management Dis- trict. P. 98. Steinbergs, C. Z. 1994. Retrofitting a golf course for recycled water. An engineer's perspective. In Wastewater Reuse for Golf Course Irrigation. Chelsea, Mich.: Lewis Publishers. Stewart, B. A., and W. L. Harman. 1984. Environmental impacts. In Water Scarcity: Impacts on Western Agricuture, E. A. Engelbert and A. F. Scheuring, eds. Berkeley, Calif.: University of California Press. U.S. Department of Agriculture. 1989. The Second RCA Appraisal: Soil, Water, and Related Resources on Nonfederal Land in the U.S. Washington, D.C.: U.S. Department of Agriculture. Williford, G. H., B. Beattie, and R. D. Lacewell. 1976. Effects of a Declining Groundwater Supply in the Northern Plains of Oklahoma and Texas on Community Service Expenditures. Texas Water Resources Institute TR-71. College Station, Tex.: Texas A&M University. Zwingle, E. 1993. Ogallala Aquifer: Wellspring of the High Plains. National Geographic. March: 80- 109.