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MANAGING WATER SCARCITY -- SOUTHWESTERN STYLE
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Arizona, located in the southwestern part of the United States, is one of
the nation's driest states, with an average rainfall of 18 centimeters
per year. Arizona is part of the Sunbelt, a band of states in the
southern part of the United States that are among the fastest growing
states in terms of population. Many older Americans are choosing to
retire in these states. Arizona also offers a range of recreational
activities that make it attractive to new residents. All of these
elements constitute an enormous challenge for the state's Department of
Water Resources as it tries to address an expanding need for a finite and
increasingly valuable natural resource.
Since before recorded history, humankind has thrived in Earth's harshest,
most hostile environments only when a reliable, clean water source is
available. In the American Southwest, the hottest and driest part of the
country, a sufficient water supply has enabled a modern society to grow
where otherwise it would not.
As the person responsible for managing the water supply in Arizona, it is
my task to make sure our 4.7 million people have a dependable supply of
clean water for personal use, agriculture, industry, and recreation.
Unlike mineral resources, water is in some sense a "renewable" commodity.
However, we cannot control where rain occurs or how quickly the snowpack
melts, so greater flexibility is warranted in water management policy
than, for example, in managing a forest ecosystem, where trees can be
cut, replanted, and later harvested on a specific location.
At the Arizona Department of Water Resources (ADWR) we:
Specifically at ADWR, we negotiate with federal and state agencies to
guarantee Arizona's long-term Colorado River water supply. Concern over
possible water shortages has resulted in the initiation of studies to
augment the Colorado River by weather modification and vegetative
management. Exotic methods of augmentation such as desalination of
seawater have been evaluated, but high costs make these schemes
infeasible at this time.
Local Philosophy
Under the U.S. government structure, primary responsibility for water
resource management rests with the individual states. Federal agencies
oversee the interrelationships among the states, especially where a
multi-state resource such as the Colorado River is concerned. The
federal government is our partner in many ventures. But if history has
taught us anything in this century, it is that local planning and local
responsibility over water supplies usually works best.
The essential advantage in a system such as this is our ability to adapt
administrative policies to local conditions. For example, in Arizona,
even though there are common climatic and topographical characteristics,
the hydrological conditions vary widely. In one desert region, there is
such an abundance of groundwater that it is prudent to allow the aquifer
to draw down significantly. In a neighboring region, however, there is a
serious groundwater overdraft. If the national government were in
control of management policy, it would be difficult to mold policy in a
timely manner to provide the best oversight of the resource. With
management at the state level, this is not so daunting a task.
The federal government took the lead in the first half of this century by
initiating a number of large water-development projects in the western
United States. Huge dams were constructed on mighty rivers such as the
Columbia and the Colorado. The U.S. Department of the Interior still
manages many of these projects.
However, the states and local governments that make use of the water are
the primary managers. In general, state agencies work to establish firm,
dependable supplies of water in their jurisdictions. The state agencies
execute contracts with other governmental entities for supplies of
surface water from rivers and reservoirs.
In our regulatory role, we set rules for drilling wells and establish
safe limits for pumping water from underground. Certain areas of our
state, for example, have experienced severe depletion of the water
supply, so it has become necessary to impose strict limits on future
pumping.
At the municipal level, city water departments ensure the water they
deliver to residential and industrial customers meets health and quality
specifications. The cities also set water rates for their various
residential and industrial customers.
Agricultural users generally obtain their water through
quasi-governmental agencies such as locally formed irrigation districts.
Survival of agriculture is an important goal, so surface water supplies
delivered to farmers are heavily subsidized. In this way, farmers are
able to get the large quantities they need at prices much lower than
municipal customers pay. As you might imagine, food prices depend
heavily on the cost of essential resources such as irrigation water.
Groundwater
For a desert environment that receives only about 18 centimeters of rain
annually, Arizona has a surprising amount of water. We are blessed with
huge underground water tables, called "aquifers," where massive
quantities of good water have been stored for millions of years. About
40 percent of the water used in Arizona comes from these groundwater
basins. Conservation of this difficult-to-replace asset for the future
is our great challenge.
Throughout this century, groundwater has been pumped out more rapidly
than it is being replenished, creating a condition called overdraft. To
reverse this trend, the state of Arizona enacted the 1980 Groundwater
Management Act. Authorities recognize the Act as one of the most
progressive groundwater management initiatives in the nation. The goal
of the groundwater code is to reach "safe-yield" by 2025. Safe-yield is
a condition where the amount of groundwater withdrawal equals the amount
of aquifer recharge (when there is a balance between water being taken
out and water coming in to the aquifer).
We have designated five groundwater basins where overdraft is occurring
as "active management areas" (AMAs). Eighty percent of Arizona's
population resides in the five AMAs. Authority to commence residential
and industrial development in these areas is subject to the ability to
demonstrate an assured water supply for 100 years.
A number of groundwater recharge projects, under the direction of the
Arizona Water Banking Authority, will be undertaken to replenish the
aquifers. It takes a long time to rebuild a depleted aquifer, if, in
fact, replenishment is possible.
Surface Water
In our largest metropolitan area, Phoenix, we have a network of canals
based upon irrigation ditches laid out and dug 800 years ago by the
original Native American inhabitants of the Valley of the Sun, the
Hohokam Indians. These ancient engineers were master surveyors, and they
determined exactly where canals needed to be dug to provide a
gravity-flow system of irrigation for their crops.
When the Phoenix area began to grow about 130 years ago, the new
inhabitants set out to improve and modernize this ancient canal system.
The dirt ditches have been lined with concrete, and additional kilometers
of waterways have been dug throughout the vast Valley of the Sun and
beyond. Today, a liter of water that enters Arizona at Parker Dam on the
Colorado River can travel upwards of 800 kilometers before it is used in
the southern part of the state.
The Salt-Verde and Gila watersheds in the eastern mountains and the Agua
Fria River in the central mountains fill a chain of lake reservoirs that
serve the dual purpose of storage and recreation. Rain and the melted
mountain snowpack offer thousands of boaters, swimmers, and fishermen a
cool respite from summer heat on these desert lakes and rivers, while at
the same time the water is being drawn down for municipal and industrial
purposes.
In times of excess runoff on the watersheds, these lake reservoirs cannot
hold all the water available. Although we do not like to do it, a
significant amount of water is released from the dams and it is not
uncommon to see normally dry riverbeds running from bank-to-bank with
rushing water. We presently are incapable of recapturing this water, and
it generally flows down the Salt-Gila system to Yuma, where it enters the
Colorado River just above the U.S.-Mexican border.
Colorado River
Phoenix and Tucson, our state's principal cities, must supplement the
water from these watersheds. A 536-kilometer concrete canal, the Central
Arizona Project, channels water from the Colorado River to Phoenix and
Tucson. This great engineering feat was made possible by a dedicated,
forward-looking group of citizens and elected representatives who were
able to envision what Arizona might become if a large and predictable
water source were available.
The Colorado River begins in the Rocky Mountains in the state of Colorado
and courses more than 2,300 kilometers to the Sea of Cortez in Mexico.
Originally, the Colorado was a wild and untamed river. At one time, it
even broke through levees in California and formed what is now called the
Salton Sea. To control the river and bring some regularity and
dependability to bear, the U.S. government in the 1930s built Hoover Dam.
It was construction of this dam, and the later Glen Canyon Dam upstream,
that made possible the modern-day miracles of the urban desert. Because
the Colorado River is so vital to the southwestern United States and
Mexico, it has become one of the most regulated and managed rivers in the
United States.
Seven states (Arizona, California, Nevada, Colorado, Utah, New Mexico, and
Wyoming) and the Republic of Mexico draw life-sustaining water from this
mighty river. Each year, more than 7.5 million acre-feet of water (one
acre-foot is about 1,238,800 liters) are allotted to Arizona, Nevada, and
California - the Lower Basin states.
The Lower Basin allotment provides water to more than 17 million people
and to more than 1 million acres of farmland. Hydroelectric plants on
the river generate about 12,000 million kilowatt-hours of electricity
annually.
As large as the Colorado system is, the potential for water shortages on
the river is real. When the allotment agreements were reached, the
annual Colorado flow was estimated at 18 million acre-feet. Today we
know the annual flow is more in the neighborhood of 14 million acre-feet,
so it is easy to understand how oversubscribed the river will be when it
is utilized fully.
Surface water from rivers, lakes, reservoirs, and elsewhere is
apportioned through a hierarchy of rights under a doctrine of "prior
appropriation."
In the United States, prior appropriation is a concept unique to the
Western states. Simply put, prior appropriation means "first in time,
first in right." In other words, the first person to put the water to
beneficial and reasonable use acquires a right superior to later
appropriators. This person or their successors have the right to use a
specified amount of water for a stated beneficial use each year, subject
only to the rights of prior appropriators.
Although the allocation of the Colorado River was not subject to the
doctrine of "prior appropriation,"" in order to get federal funding to
build the canal system to deliver Colorado River water to our state, 1.5
million acre-feet of Arizona's allocation is the "junior" use.
In years of drought, we may be required to take less from the river than
our 2.8-million acre-foot allotment. This will work a hardship for our
citizens, so we actively encourage conservation techniques and
efficiency.
Effluent Water
A fourth supply of water, obtained through the re-use of so-called "gray"
water, will play an increasingly valuable role as people become more
comfortable with the idea of using recycled effluent water. Reclaimed
water is the one increasing water source in our state. As our population
and water use grows, more treated wastewater will be available.
Reclaimed water is treated to a standard of cleanliness that permits us
to use it for a variety of purposes, including golf courses, parks,
industrial cooling, and maintenance of wildlife areas.
Initially, there can be a natural human resistance to a program of
reusing wastewater. There are a number of strategies being developed to
make this more acceptable. Most of the effluent projects under way do
not envision turning this into a supply for household uses. There is a
wide array of other potential uses for effluent. Indeed, our department
is working on plans that will permit housing developers to obtain their
assured water supplies by agreeing to exchange the effluent from the
residential projects for surface or ground water.
In addition, there are other sources of effluent besides household
wastewater. Industrial operations are large users of water, so it makes
sense to recapture and reuse significant quantities of this water. Also,
frequently there are large quantities of runoff from agricultural
irrigation that can be captured, treated, and reused. We believe the
people we serve expect us to be imaginative, resourceful, and creative in
our management practices.
Users
Agencies such as ADWR are responsible for delivering water to a variety
of users. A complex hierarchy of water rights controls who is entitled
to share from the common supply.
Native American Tribes. About 28 percent of Arizona's land -- an area
the size of Austria -- is held in trust for Native American tribes. Many
tribes have lived in the region for hundreds of years. The fact that
Native American water rights claims are usually very senior and, in many
cases, unquantified demonstrates the importance of resolving this issue.
There are two means by which Native American water rights claims are
resolved in Arizona: negotiation of water rights settlements and the
adjudication of water rights.
Establishing Native American water rights is an important point of
negotiation among state and federal agencies, in addition to the tribal
interests that claim allotments of water. States throughout the nation
are negotiating with Native American tribes to settle claims to water for
tribal purposes.
The United States Supreme Court in 1908 determined that federal
reservations for Native Americans were allocated enough water at the time
the reservations were established. Within Arizona's surface water law
doctrine of prior appropriation, the priority date of the water right
corresponds to the date a reservation was established. Generally in
Arizona, this time precedes extensive non-Native American settlement, so
Native American water rights are senior to rights held by non-Native
American users.
Until these rights are quantified, non-Native American water users with
junior water rights face considerable uncertainty when planning their
long-term water use.
Agriculture. Farmers in rural areas have long-established claims to
groundwater supplies, and they sometimes make complicated agreements to
identify and perpetuate their claims to water for their crops.
Through common associations such as irrigation districts, farmers enter
into delivery contracts with other quasi-governmental agencies such as
the Central Arizona Project, which delivers Colorado River water, and the
Salt River Project, which manages the surface water from the Salt-Verde
region.
The hierarchy of water rights places a high value on seniority, and thus
creates an active market in the sale and purchase of these rights.
Before 1919, a non-Native American person acquired a water right in
Arizona by one of two methods: simply by putting the water to a
beneficial use, or by posting a notice and recording a water right claim
with the county recorder. Therefore, the records of early rights took on
a variety of forms.
In 1919, the state legislature enacted the Public Water Code,
establishing procedures for developing a right to use appropriable, or
public, water. Since then, no right to use surface water can be acquired
except by following this strict statutory procedure, which has remained
substantially unchanged.
Cities. In the cities, municipal governments have claims on water
supplies. In a growing Sunbelt state such as Arizona, municipal water
interests will be in negotiations for decades to come in order to assure
reliable sources of water. It is part of our long-term strategy that
agricultural water rights will be converted to municipal and industrial
rights as our state becomes more urbanized and the scope of agriculture
diminishes.
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