The Arid West—Where Water Is Scarce

views updated

Chapter 8
The Arid WestWhere Water Is Scarce


The United States is a nation relatively rich in water resources. According to Susan S. Hutson et al., in Estimated Use of Water in the United States in 2000 (2004,, in the lower forty-eight states the total supply of water is about 1.4 trillion gallons per day. Nevertheless, while the nation as a whole is water-rich, this abundance is not spread evenly throughout the country. Some areas have more water than others, whereas some have a higher need than others. Those with the greatest need do not always have adequate water resources, a situation that can lead to serious problems and conflicts.

Much of the U.S. West is arid (characterized by desert land) and semiarid (prairie land), with limited and inconsistent supplies of water. The West includes Washington, Oregon, and California (the Pacific states); and Idaho, Montana, Wyoming, Colorado, Utah, Nevada, New Mexico, and Arizona (the Mountain states). From the Rocky Mountains, which form the Continental Divide, to the shores of California, lay the dry basins and deserts of this vast western region of the country.

Alfred de Grazia notes in The American Way of Government (1957) that the lower forty-eight states comprise 1.9 billion acres of land. Almost half of this land is semiarid and arid and receives less than twenty inches of precipitation per year. The small amount of rain and snow that falls is unevenly distributed. For example, the Weather Channel (April 2007, reports that Flagstaff, Arizona, receives more than twenty inches of precipitation a year, but in Phoenix and Tucson, where most of Arizona's people live and most of the agriculture is located, the yearly rainfall averages barely nine inches. The reason for this is the North Pacific high pressure system. This is a huge zone of high atmospheric pressure that is the characteristic weather pattern for the Pacific Ocean off the coast of North America. The North Pacific High pushes most precipitation toward the north.

No resource is as vital to the West's urban centers, agriculture, industry, recreation, scenic beauty, and environmental preservation as water. Throughout the history of the West, especially in California, battles have raged over who gets how much of this precious resource. The fundamental controversy is one of distribution, combined with conflicts between competing interests over the use of available supplies.


Although the climate is arid and semiarid in much of the West, and water is a necessary and less available resource than in other parts of the United States, the population of the West is booming. According to data from the U.S. Census Bureau, population growth exploded in the West between 1990 and 2000. Figure 8.1 shows that from 2000 to 2006, growth in the United States was focused in the West as well as in the South. The maps show that in terms of numbers of people, states in the West and the South had the greatest rise. In terms of percent change, two western statesNevada and Arizonahad the highest growth rate of all states from 2000 to 2006.

The Census Bureau projects that the two highest percentages of population growth from 2000 to 2030 will be in the West (45.8%) and the South (42.9%). (See Table 8.1.) The top five states with the projected highest percentage gains will be Nevada (114.3%), Arizona (108.8%), Florida (79.5), Texas (59.8%), and Idaho (52.2%).

Table 8.2 shows population growth in metropolitan areas (at least one urbanized area of 50,000 or more people), micropolitan areas (at least one urbanized area of 10,000 to 49,999 people), and areas outside either (often called rural areas). The highest growth rate in metropolitan areas from 1990 to 2000 was in the Mountain states of the West, at 36.7%. From 2000 to 2003 the Mountain states of the West had the highest growth rate again: 7.8%.


Precipitation (rain, snow, and sleet) is the main source of essentially all freshwater supplies, largely con-trolling the availability of surface water and groundwater. In the arid regions of the West, much of the available precipitation evaporates shortly after the rains stop. Tucson, Arizona, for example, receives most of its annual rainfall from heavy thunderstorms during the hottest months of the yearbetween July and Septemberwhen much of that rainfall is lost through evaporation.

Change in total population, numerical and percent, for regions, divisions, and states, 200030
Region, division, and stateNumerical change 2000 to 2010Numerical change 2010 to 2020Numerical change 2020 to 2030Numerical change 2000 to 2030Percent change 2000 to 2010Percent change 2010 to 2020Percent change 2020 to 2030Percent change 2000 to 2030
United States27,513,67526,868,96527,779,88982,162,5299.88.78.329.2
New England816,272570,739313,4871,700,4985.
   New Hampshire149,774139,191121,720410,68512.
   Rhode Island68,33337,5781,289104,6226.
Middle Atlantic1,374,529779,519222,1442,376,1923.
   New York467,215133,24899,491500,9722.
   New Jersey603,881443,404340,8051,388,0907.24.93.616.5
East North Central1,886,2861,167,410429,7313,483,4274.
West North Central1,112,371896,332612,3922,621,0955.84.42.913.6
   North Dakota5,5776,51123,54635,6340.
   South Dakota31,55515,5401,47745,6184.
South Atlantic8,022,6218,650,2459,651,19026,324,05615.514.514.150.8
   District of Columbia42,27449,24547,126138,6457.49.39.824.2
   West Virginia20,79728,02981,15388,3851.
   North Carolina1,296,5101,363,4661,518,4504,178,42616.114.614.251.9
   South Carolina434,692375,873325,9921,136,55710.88.56.828.3
East South Central1,040,901915,117923,4572,879,4756.15.14.916.9
West South Central4,283,2724,421,8435,123,87113,828,98613.612.412.844.0
   New Mexico161,179104,11615,367280,6628.95.30.715.4

Runoff refers to water that is not immediately absorbed into the ground during a rain and runs off into lower-lying areas or surrounding lakes and streams. Runoff is the primary measure of a region's water supply. Besides rain, a large share of the West's runoff comes from the melting of mountain snowpacks, which are essentially huge reservoirs of frozen water that slowly release their supplies during the spring and summer. Much of western agriculture depends on this meltwater becoming available during the growing season.

Change in total population, numerical and percent, for regions, divisions, and states, 200030 [continued]
Region, division, and stateNumerical change 2000 to 2010Numerical change 2010 to 2020Numerical change 2020 to 2030Numerical change 2000 to 2030Percent change 2000 to 2010Percent change 2010 to 2020Percent change 2020 to 2030Percent change 2000 to 2030
Source: Table 7. Interim Projections: Change in Total Population for Regions, Divisions, and States: 2000 to 2030, in Interim State Population Projections, 2005, U.S. Census Bureau, Population Division, April 21, 2005, (accessed February 10, 2007)
Population change in metropolitan areas in the U.S., 19902000 and 200003
[Numerical change in thousands. Data are for April 1, 1990; April 1, 2000, estimates base; and July 1, 2003.]
Geographic area2000200319902000
TotalMetropolitanMicropolitanOutside CBSAsTotalMetropolitanMicropolitanOutside CBSAs
Note: Metropolitan areas contain at least one urbanized area of 50,000 or more people. Micropolitan areas contain at least one urbanized area of 49,999 people. Together these areas are called core based statistical areas (CBSAs). Territory not included as either is called "outside CBSAs."
Source: "Table 2. Population Change by Core Based Statistical Area (CBSA) Status for the United States, Regions, and Divisions: 19902000 and 20002003," in Population Change in Metropolitan and Micropolitan Statistical Areas: 19902003, U.S. Census Bureau, September 2005, (accessed February 15, 2007)
Numerical change
United States9,3878,8154759732,71328,6412,6671,406
Regions and divisions
Northeast region80573951152,7862,59013759
   New England division28323832137166246428
   Middle Atlantic division5225011922,0701,9667331
Midwest region1,01198051204,7263,945510271
   East north central division68262437203,1462,613314219
   West north central division32935514401,5801,33119752
South region4,3044,0002337114,78912,7191,314756
   South Atlantic Division2,5782,359158618,2007,165683352
   East south central division3182674651,8471,287361198
   West south central division1,4071,3752854,7424,268269205
West region3,2673,0961393210,4139,387706320
   Mountain division1,2111,12567194,5143,861428226
   Pacific division2,0561,97172135,8985,52627894
Percent change
United States3.
Regions and divisions
Northeast region1.
   New England division2.
   Middle Atlantic division1.
Midwest region1.
   East north central division1.
   West north central division1.
South region4.
   South Atlantic division5.
   East south central division1.
   West south central division4.
West region5.
   Mountain division6.
   Pacific division4.

Changes in climate can adversely affect the volume of snowpacks. The U.S. Global Change Research Program (USGCRP) projects that the snowpack of the West's mountain ranges will likely decrease as the climate continues to warm, despite a projected increase in precipitation. (See Figure 8.2.) The USGCRP suggests that in the coming years more precipitation will fall as rain (rather than as snow) and that snowpack will develop later and melt earlier. As a result, peak stream flows will likely come earlier in the spring, and summer flows will be reduced. The change in the timing of runoff from snowmelt is likely to have implications for water management, flood protection, irrigation, and planning.

Surface Water

The Colorado River is a major source of water for many western states: Colorado, New Mexico, Utah, Wyoming, Arizona, California, and Nevada. (See Figure 8.3.) The Colorado River Basin is the land area that drains into the Colorado River and its tributaries. In the 2005 Review: Water Quality Standards for Salinity, Colorado River System (October 2005,, the Colorado River Basin Salinity Control Forum reports that this river supplies water to about 7.5 million people within the basin area and another 25.4 million people outside the basin area in the states mentioned previously. The forum states, "About 2.3 million acres are irrigated within the Colorado River Basin and hundreds of thousands of additional acres are irrigated by waters exported from the Colorado River Basin. Hydroelectric power facilities along the Colorado River and its tributaries generate approximately 12 billion kilowatt-hours annually which is used both inside and outside of the Colorado River Basin."

The Colorado River is managed and operated under guidelines called the Law of the River. This law is actually a collection of federal laws, state compacts, court decisions, and regulatory guidelines. Under the Law of the River, the Colorado River is apportioned among the seven basin states and Mexico, into which the Colorado River flows. (See Figure 8.3.) The legal right for a state to use a certain amount of water from the Colorado River over a given period is called a water entitlement. Aqueducts, which are artificial water channels, bring water from the river to the general area where it is needed. It is distributed to users from that point.

Along with the Colorado River, another major source of water for California are the Sacramento and San Joaquin rivers. These rivers come together at the Sacramento-San Joaquin Delta and then flow into the northern arm of San Francisco Bay. The rivers, the delta, and their location within the state are shown in Figure 8.4. Jay Lund et al. note in Envisioning Futures for the Sacramento-San Joaquin Delta (2007, that "the Delta is considered the hub of the state's water supply because it is used as a transit point for this water."

The term transit point suggests that the water is traveling somewhere, and it is. In the southern end of the delta near the city of Tracy, the California Aqueduct begins. (See Figure 8.4.) This 444-mile-long artificial channel carries water from Northern to Southern California. Much of the time the water flows by gravity, but pumps are used in certain places along the way.


The other source of water in the West is groundwater (underground supplies). Most groundwater is found in aquifers, underground saturated zones full of water within the spaces between soil and rocks, and within the rocks themselves. These saturated zones are recharged (replenished) primarily from rainfall percolating through the soils. Water from streams, lakes, wetlands, and other water bodies may also seep into the saturated zones. In the saturated zone, water is under pressure that is higher than atmospheric pressure. When a well is dug into the saturated zone, water flows from the area of higher pressure [Image not available for copyright reasons.](in the ground) to the area of lower pressure (in the hollow well), and the well fills with water to the level of the existing groundwater. If the pressure is strong enough, the water will flow freely to the surface; otherwise the water must be pumped.

The Ogallala or High Plains Aquifer is one of the world's largest aquifers. (See Figure 4.4 in Chapter 4.) According to the High Plains Aquifer Information Network (2007,, it covers 174,000 square miles stretching from southern South Dakota to the Texas panhandle and is the largest single source of underground water in the country. The U.S. Environmental Protection Agency designates the Ogallala Aquifer a sole-source aquifer, meaning that at least 50% of the population in the area depends on it for its water supply.

The Ogallala Aquifer provides water to portions of eight western and midwestern states: Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming. The southern portion of the aquifer is the largest source of groundwater for the western interior plains of the United States. Like many aquifers in the West, this once plentiful source of underground water is being depleted rapidly because its water supply is being extracted by thousands of wells at a faster rate than can be replenished through annual rainfall. Falling water tables invariably signal that the withdrawal of groundwater is exceeding the rate of replacement and that, eventually, the source of water could disappear.

Besides the southern Ogallala Aquifer as a ground-water source to some western states, groundwater is available in the southwestern desert basins. The desert basins are the valleys that lie between mountain ranges. Most of these valleys contain groundwater in layers of gravel, sand, silt, and clay, although groundwater conditions vary because of the complex geography and geology of California and other western states. Some of this groundwater is used for irrigation, public supply, and private wells.

Desert basin aquifers are recharged by rainfall and snowmelt runoff from the mountains. However, the groundwater levels are also affected by short- and long-term climatic conditions and by groundwater withdrawals, irrigation returns, and other factors. Complicating the situation is the climate: the arid and semiarid climate found in much of the West results in slow natural replenishment of aquifer water. Slow replenishment coupled with large-scale removal of groundwater results in loss of springs, streams, wetlands, and their associated habitats; degradation of water quality; and land subsidence.

Land subsidence is the sinking of the ground surface caused by the slow drainage of water from the clay and silt sediments in and next to aquifers. As water levels in aquifers decline and the water is drained from the soil, it compacts, causing the land surface to drop. Land subsidence can cause large cracks and holes in the ground, resulting in damage to roads, pipelines, buildings, canals and drainage ditches, railroads, and other structures. The U.S. Geological Survey reports in "Land Subsidence from Ground-Water Pumping" (January 6, 2004, that significant land subsidence is occurring throughout the West, such as in Mendota (twenty-nine feet in depth) and Santa Clara Valley, California (twelve feet); Eloy, Arizona (fifteen feet); Houston, Texas (nine feet); and Las Vegas, Nevada (six feet).


What Is Drought?

Drought is a deficiency of precipitation over an extended period, typically a season or more, and is usually judged relative to a long-term average condition in a particular area. Drought is also related to the timing and the effectiveness of the precipitation. Timing refers to factors such as the period when drought is most likely to occur, delays in the start of the rainy season, and the occurrence of rain in relation to principal crop growth. Precipitation effectiveness refers to the duration, intensity, and frequency of rains or other precipitation events. In many regions of the United States and the world, high temperature, high winds, and low relative humidity are also associated with drought, increasing its severity. In normally arid and semiarid regions, drought refers to dry-ness over and above the conditions of usual dry seasons.

Figure 8.5 shows drought severity across the forty-eight contiguous states for the week ending February 10, 2007. The map shows that it was extremely moist in the Northeast and areas just south of the Great Lakes. The rest of the eastern portion of the country was near normal in precipitation levels except for southern Florida, which was experiencing moderate drought conditions. Likewise, the central portion of the country was at or above normal precipitation levels except for northern portions of North Dakota, Minnesota, and Wisconsin, which were experiencing moderate to extreme drought. In the West much of Wyoming was in moderate to extreme drought. All of Arizona, most of California, and the southern tip of Nevada were experiencing moderate to severe drought conditions as well.

The interaction between drought, a natural event, and the demand that people place on water supply can worsen a drought's impact. Changes in land use, land degradation, and the construction of dams all affect the characteristics of a water basin (the land area drained by a particular river and its tributaries), and as a result, the pattern and volume of river or stream flow. For example, changes in land use upstream may alter the rates at which water filters into the ground or runs off the ground, causing more variable stream flow and a higher frequency of water shortage downstream.

Predicting Drought

Anyone can predict with absolute certainty that drought will occur somewhere on the planet, because inevitably it will. It is the how, when, where, and for what duration that are difficult to predict. Drought is never the result of a single cause, but comes from the interaction, and sometimes compounding, of the effects of many causes. On the largest scale, global weather systems play an important part in explaining global and regional weather patterns. These patterns occur with enough frequency and similar characteristics over a sufficient length of time to provide opportunities to strengthen scientists' ability to predict long-range climate, particularly in the tropics. An example of these global systems is El Niño, a disruption of the ocean-atmosphere system in the tropical Pacific Ocean.

On a lesser scale, high-pressure systems inhibit cloud formation and result in lower relative humidity and less precipitation. Regions that are under the influence of high-pressure systems most of the year are generally deserts such as the Sahara and Kalahari deserts in Africa. Most climatic regions experience high-pressure systems at some time, often depending on the season. Prolonged droughts occur when the large-scale deviations in atmospheric circulation patterns persist for months, seasons, or years.

The USGCRP is actively working to promote understanding of climate change and the implications it has for the United States. In Climate Change Impacts on the United States (2001, foundation.htm), the USGCRP states that advances in climate science are paving the way for scientists to project climate changes at the regional scale, allowing them to identify regional vulnerabilities and to assess potential regional effects. For example, the USGCRP suggests that the earth's climate has changed in the past and that even greater climate change is likely to occur during the twenty-first century. It also suggests that reduced summer runoff, increased winter runoff, and increased water demands are likely to compound current stresses on water supplies and flood management, particularly in the western United States.


California and the 198693 Drought

California is located in a climatic high-pressure zone that hovers off its coast, causing rainfall to be diverted northward. The rain that does fall in California is not evenly distributed. In general, according to the Western Regional Climate Center (2006,, the northern one-third receives forty to one hundred inches of rain per year, whereas the southern two-thirds of the state receives from five to thirty inches of rain per year, and far southern portions of the state receive less than five inches each year. Although Northern California provides two-thirds of the state's water supply, two-thirds of the state's population lives in Southern California, which has little water of its own.

Drought plagued California from 1986 until 1993, the longest dry period in nearly one hundred years of record keeping. Water supplies dwindled and water rationing was instituted. Many asked the governor to proclaim a state of emergency.

In the San Joaquin Valley, an area the size of Connecticut, the earth dropped more than a foot from land subsidence, damaging roads and buildings. Water resource authorities suspended the agricultural deliveries of water. Crops such as grapevines and fruit trees died because of insufficient water. Farmers who planted water-intensive crops such as cotton, alfalfa, and rice were the hardest hit. Grocery shoppers in every part of the country paid higher prices for some fruits and vegetables because California is the nation's largest agricultural producer.

Throughout the drought, many cities and towns in California instituted severe penalties for excessive water use. Water conservation efforts included installing low-flow showerheads and toilets; not washing cars or filling swimming pools and hot tubs; using dishwashers less frequently, and letting lawns become brown. Water was categorized either as clear (direct from the tap), gray (recycled water from showers, bathtubs, sinks, and washing machines), or black (toilet wastewater). The gray water was reused to water vegetable gardens or plants. Some Californians switched to paper plates to avoid using dishwashers. Others stopped letting the tap water run while brushing their teeth or did not wait for hot water when taking showers. As water rationing became increasingly serious, code enforcers watched for violators and issued citations with fines.

The area's wildlife and vegetation required years to recover from the effects of the drought. The drought years also had a significant impact on trees. Because of the dryness, fire officials continually battled forest fires. In 1990 wildfires forced the closing of Yosemite National Park for the first time in history. Many expensive homes were destroyed as wildfires roared through the canyons. With water from rivers and reservoirs severely limited, helicopters were fitted with large buckets to allow them to scoop water from swimming pools, if necessary.

Western Water Policy Review Act of 1992

At the recommendation of the Western Governors' Association, Congress adopted the Western Water Policy Review Act of 1992, which directed a comprehensive review of federal activities affecting the allocation and use of water in nineteen western states. The Western Water Policy Review Advisory Commission was appointed and chartered in 1995.

The commission released its findings and recommendations in 1997. In the arid West, providing adequate water supplies to meet future demands remained a top priority. Besides the need for more supplies to meet growing water demands, the commission recognized that a need existed to overhaul existing water infrastructure (irrigation canals and ditches, water piping, and water storage devices). The commission also recognized that there were legal and institutional conflicts that needed to be addressed at the federal-state level, between states, and among various water users. The commission recommended the development and implementation of an integrated, coordinated federal policy for federal activities affecting the allocation and use of water in the nineteen western states. The policy was to be developed with the full involvement of the affected states.

National Drought Policy Act of 1998

As a result of the Western Water Policy Review Advisory Commission's report, Congress passed the National Drought Policy Act of 1998. The new law established a National Drought Policy Commission to make recommendations concerning the creation and development of an integrated, coordinated federal drought policy. The commission was to seek public input on recommendations for legislative and administrative actions to help prepare for and alleviate drought's adverse economic, social, health, and environmental effects.

In May 2000 the commission released the report Preparing for Drought in the 21st Century ( The commission recommended the following national policy:

National drought policy should use the resources of the federal government to support but not supplant nor interfere with state, tribal, regional, local, and individual efforts to reduce drought impacts. The guiding principles of national drought policy should be:

  1. Favor preparedness over insurance, insurance over relief, and incentives over regulation.
  2. Set research priorities based on the potential of the research results to reduce drought impacts.
  3. Coordinate the delivery of federal services through cooperation and collaboration with nonfederal entities.

The approach of this policy was a marked shift from emphasis on drought relief to that of proactive stance of working to reduce the effects of drought. The commission stated that preparedness was the key to successful drought management and that information and research were needed to support and achieve preparedness. In addition, the commission recommended that the federal government should develop a national drought policy with preparedness at its core and that federal resources should be dedicated to this goal. The commission provided specific recommendations as to how this should be done and urged Congress to pass a National Drought Preparedness Act to achieve the implementation of the recommended policy.

National Drought Preparedness Acts were introduced into Congress in 2002, 2003, and 2005 to establish a National Drought Council within the U.S. Department of Agriculture and to improve national drought preparedness, mitigation, and response efforts. None of these bills became law.

Environmental Quality Incentive Program

Even though a National Drought Preparedness Act has not been passed, the federal government does play a role in assisting farmers to implement technologies and practices to conserve water and to lessen the long-term effects of drought. The Department of Agriculture's Environmental Quality Incentive Program (EQIP) is one such effort. Reauthorized in the Farm Security and Rural Investment Act of 2002, EQIP provides payments to the states to implement conservation practices, paying up to 75% of the cost of certain conservation practices. The National Resources Conservation Service indicates in "National Priorities Programmatic, Fiscal Year 2006" (January 24, 2006, http:// 2006/natprgmprior.html) that one of the national priorities of EQIP is "promotion of conservation of ground and surface water resources." Figure 8.6 shows that a large share of EQIP dollars goes to western states. Table 8.3 shows the exact amounts.

Water PoliciesStates Lead the Way

Water shortfalls are first and foremost a local and regional problem. Because of the lack of a cohesive federal water policy, states have become important innovators in devising ways to reduce long-term vulnerability to drought. During a widespread drought from 1976 to 1977, no state had a drought plan. In 1982 only three states had them. According to the National Drought Mitigation Center (January 11, 2007,, by 2006 forty-one states had drought plans.

Most state plans do not meet all the goals of the National Drought Mitigation Center recommended planning process. Twenty-nine of the plans address response to droughts rather than mitigation (lessening) of droughts, defining the basic linkages between local, state, and federal entities for coordinated planning and response efforts.


With water scarce in many parts of the arid and semiarid western United States, finding water, bringing it to where it was needed, and obtaining rights to use the water were extremely important aspects of survival. Two important events in the process of settling the West led to laws for the allocation of the scarce water supplies: the discovery of gold and silver in the western mountain regions and the widespread use of irrigation for crop production.

Miners searching for gold and silver diverted stream water into pipes. As a result, an informal code of water regulations started in the mining camps. The first person to file a claim to a gold or silver mine was allowed priority in getting water over any later claims. To remain the owner of a mining claim, the individual had to mark it off, take possession of it, and work the claim productively. This informal water law, conceived more than one hundred years ago, was called the prior appropriation doctrine.

A few years later, this legal practice was adopted by farmers, who needed water for irrigation. The "first in time, first in right" priority system gave the first farmers guaranteed water supplies in times of drought, which were frequent. This right to use water by both the miners and the farmers, who were the first nonnative settlers of the West, was exclusive and absolute. However, the prior appropriation and "first in time, first in right" practices used in the West were different from the system of riparian rights (the right to use water, such as a stream or lake, that abuts one's property) used in the East. Riparian rights could not be sold or transferred, whereas water rights governed by the doctrine of prior appropriation could.

As the western population expanded and states began to write down their laws and arrange them into an organized legal system, the rules for water rights and use changed. The concept of beneficial use became the basis for a landowner's rights to water. Beneficial use has two components: the nature or purpose of the use and the efficient or nonwasteful use of water. State constitutions, statutes, or case law may define the beneficial uses of water. The uses may be different in each state, and the definitions of what uses are beneficial may change over time. The right to use water established under state law may be lost if the beneficial use is discontinued for a prescribed period, frequently summarized as "use it or lose it." Abandonment requires intent to permanently give up the right. Forfeiture results from the failure to use the water in the manner described in state statutes. Either requires a finding by the state resource agency that a water right has been abandoned or forfeited.

Priority determines the order of rank of the rights to use the water in a systemthat is, the person first using the water for a beneficial purpose has a right superior to those who begin to use the water at a later date. Priority becomes important when the quantity of available water is insufficient to meet the needs of all those having rights to use water from a common source. Under a priority system, water shortages are not shared as they are under a riparian water rights system. Some western state statutes contain priority or preference categories of water use under which higher-priority uses (such as domestic water supply) have first right to water in times of shortage, regardless of the priority date. There may also be constraints against changes or transfers involving these priority uses.

EQIP (Environmental Quality Incentive Program) allocations in dollars to states, fiscal year 2006
StateTotal allocations
Source: "Environmental Quality Incentives Program FY 2006 Financial and Technical Assistance Dollars to States," in FY-2006 Conservation Program Allocations to States by Program, U.S. Department of Agriculture, Natural Resources Conservation Services, February 2006, (accessed January 12, 2007)
New Hampshire$5,459,975.00
New Jersey$5,514,610.00
New Mexico$25,244,238.00
New York$14,416,790.00
North Carolina$18,199,282.00
North Dakota$23,142,407.00
Rhode Island$4,878,410.00
South Carolina$9,794,621.00
South Dakota$22,003,929.00
West Virginia$7,448,115.00
Pacific basin$1,610,004.00
Puerto Rico$6,987,541.00

Federal Water Laws and Projects

The federal government played a role in both encouraging the economic growth and settlement of the West and developing water laws and projects. The Reclamation Act of 1902 began many years of federal involvement in constructing and subsidizing water projects in the West. The act was designed to provide subsidized water for small farmers who owned up to 320 acres. Over the years farmers and corporations have used subsidized water to farm thousands of acres by entering into arrangements in which they lease (but do not own) farms.

Based on the existence of irrigated farmland guaranteed by federal subsidies, the West grew rapidly. Cities sprang up in the deserts, attracting a large array of support industries as people from the East and Midwest moved to the Southwest to enjoy the warm, dry climate, stark beauty, and sunshine.


Because of the composition of the land in much of the West, irrigation practices created some unforeseen problems. Millions of acres of irrigated land overlie a shallow and impermeable clay layer that is sometimes only a few feet below the surface. Significant changes in the land can be caused by the interaction of irrigation water and the clay. During the irrigation season temperatures in much of the desert fluctuate between 90 and 110° F, and some irrigation water is lost to evaporation. When the water evaporates, it leaves behind chemicals called salts, which accumulate in the soil.

The water that is retained in the soil seeps downward, carrying the salts with it, until it hits the impermeable clay layer. Because the water has nowhere to go, it and the dissolved salts rise back up into the plant root zone. However, the high salt concentration in the water can interfere with crop growth. Generally, high salt concentrations hinder the germination of plants and impede their absorption of nutrients. In some cases high salt concentrations in soils have rendered them unable to grow crops. The salts accumulate in the soil as irrigation continues. Eventually, the salts become visible on the ground.

To stop excessive buildup of the salts in the soil, extra irrigation water is required to flush out the salts, generally into surface drainage or groundwater. In locations where these dissolved substances reach high concentrations, the quality of the groundwater and surface water in the area can be harmed. In severe cases the increased salinity renders groundwater and surface water useless for irrigation or drinking and contributes to degraded aquatic habitats.

Buying and Selling Water Rights

Before the mid-1980s the preferred method of getting water was to develop a new supply. As new supplies became less accessible and environmental regulations made supply development more difficult and expensive, creating mechanisms for voluntary water reallocation by buying and selling water rights became more important. Western cities and industries began looking to the agricultural community for water.

Agriculture has traditionally claimed the lion's share of the West's water supplies. If farmers or ranchers, however, could earn more money selling water to a nearby city than spraying it on their crops or watering their stock, shifting the water from farm to city would be in their economic best interest. If the city is saved from damming a local river to increase supplies or depleting an aquifer, it also benefits the environment.

Advocates of the sale of water rights maintain that a free market will allow for more efficient distribution of a source that is often subsidized and just as often squandered. Conservative politicians favor it because it reduces the federal government's role in developing new water supplies. Liberal politicians also like it because more efficient use of water could benefit the environment by lessening the need for dams, which are often environmentally harmful. Since 1981 and continuing into the twenty-first century, western state legislatures have been slowly changing the old laws dealing with water rights to make water right transfers more flexible.

Opponents to the sale of water rights maintain that the sales are draining the life from small, rural communities and can cause irreparable damage to the environment in the long run as the now waterless land is left to crack, bake, and turn into dust. The farmers and ranchers who have refused to sell their water rights are concerned about not only their own water supplies but also the surrounding weeds, dust, and barren land. Once water rights are sold, the use of the land for farming is over.

Water Banks

Not all water right transfers require that water be shifted permanently away from agriculture. Voluntary market transactions can reallocate water on a temporary, long-term, or permanent basis. A water bank (a clearinghouse between the buyers and sellers of water), acting as a water broker and usually subsidized by the state, can be authorized to spend money to buy water from farmers or other sellers who are willing to temporarily or permanently reduce their own use. The bank then resells the water to drinking water suppliers, farmers, ranchers, and industries that need the water.

In Analysis of Water Banks in the Western States (July 2004,, Peggy Clifford, Clay Landry, and Andrea Larsen-Hayden note that water banks exist in almost every western state and are "emerging as an important management tool to meet growing and changing water demands throughout the United States." Clifford, Landry, and Larsen-Hayden identify California, Arizona, and Idaho as states having water banks with a high level of activity.


According to the fact sheet "Desalination" (2007,, the American Water Works Association notes that there are over 15,000 desalination plants operating in 120 countries. These plants convert seawater, brackish water (a mixture of sea-water and freshwater), and wastewater to freshwater suitable for a variety of purposes. The World Health Organization, in Nutrients in Drinking Water (2005,, explains that "about 63% of the capacity [to desalinate water] exists in West Asia and the Middle East." According to the Saudi Arabia Information Resource (March 8, 2007,, Saudi Arabia is a country heavily invested in this technology; it has twenty-seven desalination plants that provide 70% of the country's drinking water. However, Heather Cooley, Peter H. Gleick, and Gary Wolff report in Desalination, with a Grain of Salt: A California Perspective (June 2006, that worldwide, desalination plants in service in 2005 had the capacity to provide only 0.3% of the freshwater used globally.

According to Cooley, Gleick, and Wolff, 56% of global desalination plants are designed to process sea-water. Twenty-four percent can process brackish water, and the remaining desalination capacity worldwide is used to desalinate other kinds of water, such as wastewater.

In the United States desalination has become a rapidly growing alternative to water scarcity. With population growth and the threat of drought throughout the United Statesparticularly in the western states and Floridadesalination, once considered too expensive, is looking more attractive. In fact, Cooley, Gleick, and Wolff indicate that in 2005 the United States was second only to Saudi Arabia in its desalination capacity.

The growth in the use of desalination was fueled by the adoption of the Reclamation Wastewater and Groundwater Study and Facilities Act of 1992. The act directed the secretary of the interior to undertake a program to investigate and identify opportunities for water reclamation and reuse and authorized participation in five water-recycling projects. In 1996 Congress reauthorized the act, expanding it to include another eighteen projects, eight of which are in Southern California, an area in desperate need of water. At the same time, Congress enacted the Water Desalination Act of 1996. The act is based on the fundamental need to find additional sources of potable (safe to drink) water. Its primary goal is development of more cost-effective and technologically efficient means to desalinate water.

Cooley, Gleick, and Wolff state that by January 2005 over two thousand desalination plants had been installed or contracted to be installed in the United States. About 51% of this desalination capacity was used to process brackish water and 26% to process river water. Only 7% of the U.S. desalination capacity was used to desalinate seawater.

Desalination is the removal of dissolved minerals (including, but not limited to, salts) from seawater, brackish water, or treated wastewater. A number of technologies have been developed for desalination. In the United States desalination research is directed by the Bureau of Reclamation, which is a branch of the U.S. Department of the Interior.

There are several desalination processes:

  • Reverse osmosisfiltered water is pumped at high pressure through permeable membranes, separating the salts from the water.
  • Distillationwater is heated and then evaporated to separate out the dissolved minerals. The most common methods of distillation are:
    1. Multistage flash distillation, in which the water is heated and the pressure lowered so that the water flashes into vapor that is drawn off and cooled to provide desalted water.
    2. Multiple effect distillation, in which the water passes through a number of evaporators in series with the vapor from one series being used to evaporate the water in the next series.
    3. Vapor compression, in which the water is evaporated and the vapor compressed; the heated compressed vapor is used to evaporate additional water.
    4. Electrodialysiselectric current is applied to brackish water, causing positive and negative ions of dissolved salt to split apart.

The two most common desalination processes worldwide are multistage flash distillation and reverse osmosis. Although water of different quality, including seawater, brackish water, or impure industrial wastewater, can be desalinated, seawater and brackish water are the most common water sources worldwide.

Desalination Plants in the United States

Buckeye, Arizona, became the first town in the United States to have all its water supplied by its own electrodialysis-desalting plant. Starting in 1962, the plant provided about 650,000 gallons of water daily at a cost of about $1 per 1,670 gallons. In 1967 Key West, Florida, opened a flash-evaporation plant and became the first city in the United States to draw its freshwater from the sea. Cooley, Gleick, and Wolff note that as of January 2005 the states having desalination capacity of more than 1% of the total U.S. capacity were, from most to least: Florida, California, Arizona, Texas, Virginia, Colorado, Pennsylvania, Ohio, Alabama, North Carolina, Utah, Oklahoma, and Hawaii.

According to the Bureau of Reclamation's Yuma Area Office (March 2007,, the Yuma desalting plant in Arizona is the largest reverse osmosis desalting plant in the world. The plant was built as a result of a dispute with Mexico over the salinity of drainage water from the Wellton-Mohawk Irrigation District in Arizona. The salinity of this irrigation return flow caused marked deterioration in Colorado River water quality in Mexico. The problem was so severe that Congress enacted the Colorado River Basin Salinity Control Act to fund the plant's construction.

This is how the plant works: The saline drainage water from farmlands east of Yuma flows in a concrete drainage canal to the desalting plant. The drainage water enters the plant intake system, where screens remove algae and large debris such as tree limbs. As the drainage water flows into the plant, it is treated with chlorine to kill organisms and stop the growth of algae, which would damage or plug the filters and membranes. Before being desalted, the water passes through several pretreatment steps to remove all solids that would interfere with the membrane performance. Pretreatment extends the life of the reverse osmosis membranes three to five years. Without pretreatment, the membranes would last about one hour. It takes only a few hours for a unit of water to travel through the plant, from where it enters as untreated drainage water, is pretreated and subjected to reverse osmosis, and then discharged to a small canal that empties into the Colorado River.

Cooley, Gleick, and Wolff describe how California is proposing an expansion in its desalination capacity that would increase its seawater desalination capacity by sev-entyfold. Figure 8.7 shows the locations of the proposed desalination plants. Eleven of the plants were proposed for Northern California and ten for Southern California. Of the twenty-one proposed plants, twelve are slated to be larger than any previous desalting plants built in that state. (Note that not all the proposed plants have remained under active consideration.)

Advantages and Disadvantages of Desalination

One of the most important factors determining whether desalination is a viable way to provide water to consumers is cost. Cooley, Gleick, and Wolff calculate that desalination of water in California will cost users between $3 and $10 per thousand gallons. There are many reasons, such as subsidies and energy costs, for the large variation in the price, but one major reason is the cost of water distribution in various regions of the state. This price range is far above prices consumers generally pay for water. Farmers may pay as little as $0.20 to $0.40 per thousand gallons, whereas consumers living in urban areas may pay $1 to $3 per thousand gallons. Clearly, desalinated water is expensive, and while the long-term trend in desalination costs has been downward, in recent years prices have increased because of rising energy and construction costs. In the early 2000s cost estimates for new plants were noticeably higher than those for similar plants built just a few years earlier

Nonetheless, desalination can provide a reliable source of water independent of the weather and can provide an additional source of water to those already in place. In addition, the desalination process removes water impurities. However, water quality must be monitored to ensure than contaminants are not added during the desalination process or that essential minerals are not removed.


Wastewater from sewage treatment plants is one of the largest potential sources of freshwater where supplies are limited. After it has been treated to kill pathogens (disease-causing organisms) and remove contaminants, it can be reused for irrigation and industrial use and to maintain stream flow.


The five realities of water in the West

Five interrelated realities of water management will shape, if not control, policy level water supply decisions in the West through 2025:

1) Explosive population growth in areas of the West where water is already scarce.

2) Water shortages occur frequently in the West.

3) Over-allocated watersheds can cause crisis and conflict.

4) Water facilities are aging.

5) Crisis management is not effective in dealing with water conflicts.

source: Adapted from "Water 2025 Realities," in Water 2025: Preventing Crises and Conflict in the West, Water 2025 Status Report U.S. Department of the Interior, Bureau of Reclamation, August 2005, (accessed January 11, 2007)

Indirect reuse of treated municipal wastewater (reclaimed water) is becoming increasingly attractive to many municipalities, especially in the West. For example, the Orange County Water District in California has implemented the Green Acres Project, which uses reclaimed water for landscape irrigation at parks and schools, as well as for various industrial uses. According to the district (October 31, 2001,, the project can purify up to 7.5 million gallons per day of reclaimed water from the Orange County Sanitation District. Using a newly built reservoir, the project can store up to 350 million gallons of this recycled water per year.

WATER 2025

Problems in the West, including explosive population growth, existing water shortages, conflicts over water, aging water facilities, and ineffective crisis management, have led to a Interior Department proposal designed to assist communities in addressing these needs. In Water 2025: Preventing Crises and Conflict in the West (August 2005,, the Interior Department calls for concentrating existing federal financial and technical resources in key western watersheds and in critical research and development, such as water conservation and desalinization, that will help predict, prevent, and alleviate water supply conflicts. Table 8.4 outlines the five realities of water in the West as identified in the report.

Water 2025 emphasizes the need for states, tribes, local governments, and the public to decide how best to resolve the water supply crisis in the West. As part of this plan, the Interior Department prepared an analysis of potential water supply crises and conflicts that may occur by 2025. The department intended to seek extensive input from states, tribes, and the public on the prepared analysis to revise and improve the analysis as needed.

Water 2025 is a departure from previous plans in that it focuses on strategies and measures that can be put in place before events such as drought will bring further divisiveness to communities in the West. The department believes that conflict can be minimized or avoided when potential water supply crises are addressed in advance by local and regional communities. Figure 8.8 shows areas of potential water supply crises by 2025. The four key tools of the Water 2025 water-crisis prevention efforts are:

  • Water conservation, water-use efficiency, and the use of market-based approaches
  • Collaboration
  • Improved technology
  • Removal of institutional barriers and increase in interagency coordination


Water 2025 identifies supervisory control and data acquisition systems as one area in which water conservation efforts can be improved in the management of rivers. These systems allow river managers to remotely monitor and operate key river and canal facilities on a real-time basis. The Interior Department recommends that individual stations be set to monitor river levels or flow rates continuously. This will help the Interior Department and water district managers respond to daily water management needs and emergencies in a timely fashion by controlling pump and canal facilities remotely. The Interior Department notes that even though the cost of this high-tech equipment has become more affordable over time, less than 20% of irrigation water delivery systems use this technology.

Water 2025 notes that for every dollar spent on canal modernization (such as rehabilitating canal gates), an expected return of $3 to $5 in conserved water can be achieved. In addition, for every dollar spent on maintaining an existing canal lining, a return of up to $10 in conserved water can be achieved. Canal-lining technologies have reduced seepage losses in central Oregon by as much as 50%.

Additional measures recommended by Water 2025 include improvement in design and construction of new measuring devices for irrigation water delivery systems, continued support for water banks and water markets, and interagency efforts to coordinate existing and new water conservation programs.


Water 2025 points to litigation over competing water rights as one of the problems affecting water supply and conservation efforts in the West. Water managers sometimes must wait years or even decades until adjudication (consideration of the facts and rendering a decision) is completed. In the meantime they do not know how to allocate water in times of scarcity. The Interior Department is finding ways to accelerate court proceedings to protect existing federal and nonfederal rights.

An example of successful facilitation efforts occurred in California. According to the Bureau of Reclamation, for more than two decades the East Bay Municipal Utility District and several localities struggled over the management of the Sacramento River, resulting in the disruption of the efficient use of water. Facilitation sponsored by the bureau led to a sustainable and locally developed agreement among the interested parties.


Recognizing that waste-water, saltwater, and other impaired water can be purified to increase their usefulness, the Interior Department is researching ways to reduce the high costs that impede the adoption of new water purification technologies including desalination.


According to the Interior Department, in some areas of the West federal facilities have excess capacity during certain times of the year that could be used to satisfy unmet demands elsewhere. Sometimes this excess capacity is not available because of policy or legal constraints. The department believes that in some cases this additional capacity can be made available with appropriate changes in its policies.

The Interior Department is cooperating with other federal agencies to more effectively focus federal dollars on critical water shortage areas. Through active support of the National Drought Monitoring Network the department is helping accelerate the development of strategies for drought preparedness.

Additional measures include the formation of drought action teams to focus scarce resources quickly when and where they are needed, and the publication by the Geological Survey of water resource assessments online so that decision makers can better understand the water supply component of drought conditions.

About this article

The Arid West—Where Water Is Scarce

Updated About content Print Article