Research: Tamarisk’s Water Greed Overstated
Tamarisk have long been considered an outlaw plant in the West, an ecological
misfit that has infested waterways at the expense of native vegetation
and water supplies. What then would be the water savings if tamarisk,
also called salt cedars, were removed from along rivers?
Recent research is questioning the general consensus that the water savings
would in fact be significant. Pat Shafroth, a plant ecologist for the
U.S. Geological Survey, found that cottonwood and willows, both native
species, consume about an equal amount of water as do tamarisk. In areas
where cottonwoods and willows grow as densely as tamarisk no measurable
difference in water savings is apparent.
Replacing tamarisks with cottonwood therefore would not necessarily result
in significant water savings.
Shafroth advocates looking at the system as a whole and not define the
issue as tamarisk-versus-no-tamarisk. He calls for additional research
to quantify actual water savings from removing tamarisk upstream.
Joe Lewis, an economist for the National Invasive Species Council, reported
that a new tamarisk study to be completed at the end of the year offers
similar preliminary conclusions.
The same report indicates that water savings were significant, however,
in areas with growths of native grasses and shrubs instead of tamarisk.
A minimum water savings of at least 30 percent and up to 60 percent were
reported.
The above findings run counter to the position held by many ecologists
and politicians that replacing tamarisk with native vegetation would result
in significant water savings and help relieve drought conditions. This
strategy is strongly advocated for along the Colorado River.
For example, in 2003 Sen. Pete Domenici introduced the Salt Cedar and
Russian Olive Control Demonstration Act (S.177). The bill authorizes a
research and demonstration program to accelerate the eradication of salt
cedar and other non-native species thriving along rivers in the western
United States.
The research was presented at the Tamarisk Symposium held in Grand Junction,
Oct. 12-14. The Tamarisk Coalition and the Colorado State University Cooperative
Extension cosponsored the event.
Report: Plan to Protect Grand Canyon Failing
Native fish populations continue to decline and sandbars along the Colorado
River erode despite a decade’s worth of efforts to regulate river
flow within the Grand Canyon to ensure environmental benefits. That was
the conclusion of a recent U.S. Geological Survey report.
Steps were taken in 1996 to protect the Grand Canyon by raising the dam’s
lowest water release level from 5,500 to 8,000 cubic feet per second and
lowering its highest release from 30,000 to 25,000. The intent was to
reduce the fluctuation of river flow that was believed to cause erosion.
The decision reduced power production by a third.
The report found that populations of the endangered fish population have
declined significantly and nonnative fish populations of rainbow and brown
trout have increased; nor have the low fluctuating river flows benefited
beaches and sandbars.
The outlook, however, is not entirely bleak. About a year ago scientists
released a single large burst of water from the dam. The 41,000-cubic-feet-per-second
release washed about a million tons of new sand on beach areas and renewed
sandbars. The release was timed to coincide with the canyon’s tributaries
sending peak sand loads. The tactic was successful and holds promise for
future canyon reconstruction.
The drought may have provided an environmental boost by warming water
temperatures below Glen Canyon Dam. This has provided a more hospitable
environment for the endangered humpback chub.
Whatever steps might be taken to improve the situation would likely be
at the expense of power generation – more water released, less power
generated and less revenues.
In response to the report, two environmental groups, the Center for Biological
Diversity and Living Rivers, filed notice that they intend to sue the
responsible agencies to force a reconsideration of current river management
practices.
The report, “The State of the Colorado River Ecosystem in Grand
Canyon,” is available at: http://www.gcmrc.gov/products/score/2005/score.htm
Babbitt Urges Strong Federal Land-Use Planning Role
He says same federal strategy
could be used that prompted Arizona’s GMA
Bruce
Babbitt, former Arizona Governor and U.S. Interior Secretary, visited
the University of Arizona Nov. 17 to promote his new book “Cities
in the Wilderness, A New Vision of Land Use in America.” His visit
included a talk in which he said that explaining disasters such as what
occurred in New Orleans as an act of God is to “give God a bum rap,”
whereas lack of planning is the true culprit. He called for the federal
government to provide strong incentives for states and regions to undertake
land-use planning, mentioning as a model the federal role that pressured
Arizona to pass its 1980 Groundwater Management Act. The afternoon event
was sponsored by the UA’s Water Sustainability Program and the Water
Resources Research Center. (See Publications, page 8 for review of Babbitt’s
book).
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| Compact Heads Off Arizona’s Claim to Great Lakes
Water Most Arizona water officials would readily agree that whatever additional water resources become available to the state would likely be the result of water management strategies or conservation efforts. Not high on any list would be acquiring water from a distant region of the country, say the Midwest, or from Canada. Yet it may be a sign of the times — this era of drought and global warming — that the topic of tapping into very distant water sources is seeming in some quarters less a heroic and unlikely hydrological feat and more within the realm of the possible. Such projects are appearing less far-fetched. Governors of the states bordering the Great Lakes see it that way, and they are taking no chances. The eight governors have taken defensive action, working out what might be viewed as a Great Lakes’ version of the Colorado River Compact. Called the Great Lakes Basin Water Resources Compact, the agreement identifies those who can and cannot draw water from the Great Lakes. The document declares that the waters of the Great Lakes “are precious public natural resources shared and held in trust by the states.” The states want to ensure their control of the waters of the Great Lakes in the face of increasing national and even international demand. The Great Lakes states are taking the initiative before the federal government steps in and takes action. The governors want their standards included within U.S. law prior to the 2110 census. At that time Arizona and other western and southwestern states are expected to gain additional congressional seats. Water is increasingly viewed as a commodity, and the governors are concerned that Congress, which regulates interstate commerce, will be having more say about its distribution and use. The governors fear that water-needy western states with burgeoning populations and scarce water resources will have the political muscle to stake a claim on Great Lakes water. As the compact evolved greater emphasis was placed on efficient water use among the states. An official said, “It’s hard to say no to Arizona if we’re not being smart with our own resources.” After the governors sign the compact on Dec. 13 in Milwaukee, the agreement must then be approved by the eight state legislatures and Congress. This is likely to be a formidable undertaking. The cluster of lakes contain about one-fifth of the world’s and 90 percent of the U.S.’s fresh water. Will Canadian Water Flow to the U.S. — Then to the Southwest? One of the seemingly unlikeliest of water resource strategies was the proposal to acquire water from the Yukon, transport it through Canada into the Great Lakes and ultimately to the Southwest. Proposed in the 1970s, the idea did not make much headway in water affairs. That was then; now is now. Change is literally in the air, with green house gas emissions warming the earth. According to an article that recently appeared in The Walrus, a Canadian publication, thinking big or outside the box are strategies for coping with the results of global warming. Titled “The Melting Point,” the article is subtitled “How global warming will melt our glaciers, empty the Great Lakes, force Canada to divert rivers, build dams, and, yes, sell water to the United States.” Journalist Chris Wood says global warming bodes major changes for Canada. Thawing will be a force to be reckoned with for a country whose most bountiful and prevailing natural resources are snow and ice. He says Canada’s water infrastructure is designed to cope with the current timing, frequency, quantity and distribution of snow and rain. The changes that global warming portend will disrupt the pattern. Some parts of Canada will be wetter than ever before while others dry up. For example, northern British Columbia’s share of the “water wealth” is expected to increase while the Great Lakes Basin will likely dry and record a deficit. Wood says the current infrastructure will be unable to cope with massive floods nor reduce the stress of droughts of the future. He says some bold proposals are gaining scientific credence: the diverting of major rivers to drought-plagued regions and the constructing of massive dams to contain runoff from rain that previously froze as snow and ice in the Rocky Mountains. Wood then describes an even broader issue. Unconfined by borders, droughts and floods will affect both Canada and its southern neighbor, the United States; international water politics will likely come to the forefront. What previous international stratagems have been unable to accomplish atmospheric change might achieve: international Canadian-U.S. water transfers and management of river systems. In this regard Wood quotes the Meteorological Service: “The stresses of climate change make coordinated binational management of Great Lakes waters (as well as other boundary waters) more imperative. Resolving these issues may involve changing current policies or legislation.” He believes that Canadians need to reconsider their attitude of “aqua-nationalism,” a view that holds as anathema that Canadian water be traded as a commodity, especially with the United States. He writes, “We’ll need to open our minds to new ways of sharing water and its management with the United States.” As Canada builds dams and diverts rivers to serve its needs cooperative arrangements with the United States will become more feasible. For example, one proposal for delivering water from northern Canada to parched southern regions is to divert water from Shuswap Lake, water that would eventually flow into the American reaches of the Columbia River. Dams along the river system could be managed to benefit both nations. Fears that climate change may diminish the Great Lakes by as much as 40 percent has prompted speculation that fresh water entering St. James Bay could be diverted to replenish the lakes. Such a massive project would clearly have to be a bi-national undertaking. The proposed project even has a name: the Great Recycling And Northern Development (GRAND) Canal. Wood even foresees possibly implementing elements of the Northern American Water and Power Alliance. Conceived in 1964, NAWPA would have transported 110 million acre-feet of water annually (about eight times the average annual flow of the Colorado River) from Alaska and northern Canada to the western United States and northern Mexico. He suggests that the United States might be more than willing to contribute billions of dollars to complete transfer projects if they also include delivering much needed water south to the United States. The article is available on-line at http://www.nwra.org/fea_water.pdf |
Phoenix, Las Vegas got
them worried |
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