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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 126
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 127
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 128
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 129
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 130
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 131
131
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OCR for page 132
32
A NEW ERA FOR IRRIGATION
14000000
1 2000000
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8000000
6000000
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o
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Cl
l l ~ it
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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 133
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 134
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 135
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 158
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 159
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.
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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
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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
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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.
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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.
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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
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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
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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.
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Representative terms from entire chapter:
water quality