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| A piecemeal approach to either
managing or restoring the Colorado River basin ensures success
for neither |
By John C. Schmidt
for Headwaters News |
| Although the notion of watershed thinking permeates the education of young scientists
and natural resource managers, we have forgotten "to think like a watershed" in
considering the environmental future of the Colorado River.
Watershed thinking envisions all of the opportunities and constraints that exist
in a drainage basin. Watershed decisions balance those opportunities and constraints.
The need for watershed thinking has become apparent to me in the midst of pursuing
a research program concerning management of dams and the restoration of regulated
rivers throughout the Intermountain West. My colleagues and I conduct studies
downstream from several dams and diversions in the Colorado River basin.
Two challenges in the restoration of the Colorado River are now apparent. One
is that restoration is a very difficult task, involving interdisciplinary science,
which requires courageous decisions about changing dam operations or removing
dams entirely. The second challenge is that we cannot restore the entire basin.
Restoration means the return of an ecosystem to its pre-disturbance regime. Such
a goal is politically impossible at the watershed scale, because it would require
dismantling the entire water delivery and power production infrastructure that
serves millions of people.
Is the Grand
Canyon
Thus, we are left
with the option of pursuing more modest environmental management
goals, more properly called mitigation
or rehabilitation. We are presently on
this mitigation path throughout the basin. However, we might take a different
path and pursue real restoration in a few places.
Watershed thinking would clarify either path. If we stay on the mitigation path,
a watershed scale evaluation of comparative costs and benefits would identify
the relative merits of the various basin programs. Taking a new path and pursuing
real restoration in a few places requires a watershed scale assessment of where
this effort ought to be undertaken and at what cost.
John Wesley Powell argued that the West's counties should be organized
by small watershed boundaries, because the success of agricultural settlements
lay in wise management of local water resources.
In the modern West, the interdependencies among agriculture, urban areas and
natural river processes are more extensive. Agricultural fields in the Imperial
Valley, municipal users in Tucson and Las Vegas, and the Colorado River delta
ecosystem in Mexico all depend on snowmelt runoff from the Wind River Range and
the spine of the Colorado Rockies.
Power users in southern California and northern Utah partly depend on electricity
produced at Hoover and Glen Canyon dams. Some of the base flows of the Rio Grande
that maintain habitat for the endangered silvery minnow come from the Colorado
River basin, delivered by tunnel from the San Juan River.
Watershed thinking was an early concept used in planning development of the Colorado
River. Other states in the basin recognized that the "first in time, first
in right" principle might be applied at the watershed scale and thereby
institutionalize California's rights to most the river's flow.
Would
restoration
In response, the seven basin states negotiated a watershed-scale
agreement concerning future uses -- the Colorado River Compact
of 1922. California immediately benefited
from construction of Boulder Dam and the All American Canal, and the other states
benefited by reserving a perpetual right to a proportion of the river's
flow.
Subsequent agreements about the river have been more narrowly focused. In the
1940s and 1950s, water developers conceived an integrated plan for development
of the upper basin: the Colorado River Storage Project. This scheme involved
construction of Glen Canyon Dam, Flaming Gorge Dam, Navajo Dam, and three dams
on the Gunnison River. Revenue generated by hydroelectric power funded dozens
of irrigation projects and supplied water to urban areas outside the watershed.
In 1963, an integrated plan was proposed for the downstream half of the basin
that linked hydroelectric power produced at dams in Grand Canyon with the power
needs of the Central Arizona Project. The public debate over this scheme was
the last at the half-basin scale. Subsequent water development proposals are
now debated for smaller areas: the Virgin River basin, the streams of the Uinta
Mountains, and the Animas and LaPlata River basins.
Mandates to reverse undesired environmental changes are also pursued on relatively
small spatial scales. These mandates include the Endangered Species Act, applied
to the basin's endangered endemic fishery and some of its bird species,
and the Grand Canyon Protection Act.
The Grand Canyon Protection Act is focused only on the segment between Glen Canyon
Dam and Lake Mead reservoir. The Endangered Species Act provides only a limited
mandate for river restoration because the act concerns species and not ecosystems.
Its implementation is disaggregated into recovery programs for the upper Colorado
and Green Rivers, the San Juan River, and the Virgin River.
A separate Lower Colorado Multi-Species Recovery Program focuses on ecosystem
resources downstream from Hoover Dam. Each restoration effort operates under
restrictive geographic guidelines that prevent consideration of the larger context
of river restoration.
Even the most innovative restoration programs in the basin face great challenges,
despite the fact that they are on the mitigation path. The Grand Canyon Adaptive
Management Program is charged with making recommendations that meet the goals
of the Grand Canyon Protection Act. The program brings together representatives
of the basin states, traditional water development interests, Indian tribes,
recreational interests, and environmental groups.
The program is innovative in its inclusion of a broad range of river stakeholders,
its attempt to pursue scientifically-based adaptive management, and its willingness
to use Glen Canyon Dam as an instrument of river rehabilitation. Presently, the
program is considering larger scale changes in dam operations, including autumn
restoration floods and downstream transfer of sediment from Lake Powell reservoir.
Despite its innovative organizational structure, changes in operations of Glen
Canyon Dam throughout the past decade -- limiting maximum power plant capacity,
limiting daily changes in discharge, creating floods by bypassing the power plant,
base loading the power plant for several months – have yielded little long-term
benefit in the health of the native riverine ecosystem despite significant cost
to hydropower production and flexibility in water resource management.
We have learned that it is extremely hard to restore a geomorphic system that
has such a large deficit in sediment supply, and to restore a natural ecosystem
that is fragmented by two large reservoirs that isolate Grand Canyon from the
rest of the basin.
The limited achievement of environmental goals despite large costs suggests the
inherent value of comparing the costs and benefits of the various mitigation
programs in the basin. For example, the lost power production capacity at Glen
Canyon Dam is approximately equivalent to all the production at Flaming Gorge
Dam.
Is the Grand Canyon the best place to incur lost power production for the purpose
of saving endangered species, or is the Green River below Flaming Gorge Dam a
better place to save the same species? Would the same costs to the hydropower
system incurred at Glen Canyon Dam have greater environmental benefits elsewhere?
No one asks.
The challenges at Grand Canyon suggest that we might ask other questions. Would
restoration of the basin's endangered fishery be better served if Flaming
Gorge Dam were removed, thereby restoring a wild hydrology to the Green River,
and trade-off less constraints at Glen Canyon Dam? Is mitigation in Grand Canyon
a wiser strategy than restoration of the Green River? No one asks.
Since we can not restore the entire river, we are necessarily forced to either
pursue mitigation everywhere or to decide which places to pursue true restoration.
Such an analysis demands watershed thinking. Failure to step back and look at
the entire watershed risks spending large amounts of money achieving small gains
and missing the chance to restore a natural ecosystem in a few places.
Today's drought is encouraging re-emergence of watershed thinking. But
ironically, watershed thinking is being advocated by the traditional consumers
of water and power and not by the environmental community or river restoration
programs. Lower-basin states again cast a covetous eye on unused upper-basin
water. The Republican candidate for governor in Utah advocates marketing "unused"
Green
River water downstream.
Similarly, it is time to think like a watershed regarding environmental policy
in the basin. It is time to evaluate the sum of all of the basin's dam
management and species recovery programs as if they were all linked, because
they are.
Watershed thinking about environmental policy also extends beyond policy about
river mitigation or restoration. Development of a sustainable future for the
Colorado River delta requires a comprehensive perspective of water use and allocation
that extends to the hayfields of Pinedale and the coal fields of Craig.
Management of national parks in the watershed requires a consistent policy towards
non-native invasive species such as tamarisk and toward the endangered terrestrial
and avian species that now occupy some dam-created riverine environments.
Identification of appropriate dams for decommissioning requires knowledge of
gains and loses at each site. Decisions on the future of artificial reservoir
and tailwater trout fishing recreation requires assessment of the recreational
potential of the entire watershed. Allocating scarce water supplies in the basin
requires knowing the locations of the highest and best off-stream uses, regardless
of past agreements.
Watershed thinking once spawned basin-wide plans for water resource development.
Watershed thinking can also initiate innovative thinking about the basin's
environmental future.
John (Jack) C. Schmidt is an assistant professor in the Department of Aquatic, Watershed, and Earth Resources in Utah State University's College of Natural Resources. |
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Analysis:
Rising demand, lower
flows threaten river
By Shellie Nelson, assistant editor
Headwaters News
Oct. 26, 2004
The Colorado River is already the most regulated river in the United States.
The 1,360-mile-long river is fifth-longest in the nation and winds its way
through Arizona, California, Colorado, New Mexico, Utah and Wyoming. The Colorado
River Basin represents approximately one-twelfth of the area of the continental
United States.
Despite the size of its basin, the Colorado River is only sixth in the nation
in terms of water volume. For comparison's sake, the Columbia River's basin
is about the same size in geographic terms, but has nearly 12 times the flow.
But average
annual rainfall in the three states that make up the Columbia River basin
averages about 25 inches a year; in the seven states within which the Colorado
Basin lies, the average annual rainfall is only 10.5 inches.
More water from the Colorado River Basin is exported from the basin than from
any other river in the United States. More than 24 million people in Phoenix,
Albuquerque, Las Vegas, Salt Lake City, Denver, Los Angeles, San Diego and
hundreds of other communities in the western United States depend on the Colorado
River for their water supply.
The first foray into regulating the the Colorado river came in the form of
the the Colorado River Water Compact of 1922, conceived as a way for other
states in the Colorado River Basin to protect
their water supply from fast-growing California.
When the agreement was drafted, the total population of the United States
was approximately 106 million, and 6.1 million of those people, or 5 percent,
lived in the seven member states. By 2000, the population of those states had
grown to 49 million, or 17 percent of the nation's total population of 281.4
million.
The compact divided the watershed into an upper and lower basin with Arizona,
Colorado, New Mexico, Utah and Wyoming comprising the upper basin and Arizona,
California, Nevada, New Mexico and Utah in the lower. The dividing line between
the two basins is at Lee's Ferry, Ariz., approximately 17 miles below where
Glen Canyon Dam is located today.
Each basin gets 7.5 million acre-feet of water annually from the Colorado
River, and the lower basin has the right to increase that annual use by 1 million
acre-feet annually.
The dramatic shift in population and the increasing demand for water has put
Arizona, Nevada and California at 100 percent of their allocation of Colorado
River Water.
The agreement facilitated the building of 20 or more dams along the Colorado
River and its tributaries, changing forever the face of the basin and the character
of the river.
Glen
Canyon Dam, which was completed in 1966, is blamed for the extinction
of four of the eight native fish species, the disappearance of river otters
and muskrats, and the threatened disappearance of birds, frogs and lizards.
Now the Colorado River has another set of federal regulations which may again
change the face of the river. The Endangered Species Act of 1973 brought with
it another set of demands and requirements on the Colorado River and its basin,
three-fourths of which is federal
land, either national forests and parks or Indian reservations.
The Endangered Species Act is driving federal and state government efforts
to rehabilitate portions of the Colorado River. Federal and state officials
fear further reduction in numbers of several species will trigger water restrictions.
The latest project is a $620
million joint effort between the federal government and Arizona, California
and Nevada to restore habitat along 342 miles of the lower Colorado River.
Increasing demands, both from population growth and restoring
species habitat, coupled with crippling drought has heightened awareness of
the limitations
and needs of the Colorado River Basin on a regional and national basis.
Along
with that heightened awareness, are more parties demanding a place at the well.
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