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Show Test Flooding Through Grand Canyon Is For More Environmentally Sound Water Management Says Babbitt In a Washington DC news release from the Department of the Interior, it was announced that Secretary of the Interior Bruce Babbitt initiated a first-of-its-kind test at Glen Canyon Dam on the Colorado River March 26 to replicate seasonal pre-dam flooding of tne river and to restore natural beaches and wildlife habitat in the Grand Canyon. On the previous day, March 25, Babbitt had rafted down river from Glen Canyon Dam to observe beach, habitat, and riverine conditions. "After so many years of concentrating on water capture and power generation, this test is a symbol of our new commitment to making environmental restoration an equal part in the water equation of the West," Babbitt said. "Yes, water is scarce in much of the West, and our great dams help provide for economic development. But we only have one Grand Canyon. Our science is now such that we can recreate more natural river flows without real sacrifices of power or water capture. "It has taken President Clinton's commitment to environmental restoration to do this. No one has ever tried it before. Indeed, only two decades ago a . Republican Administration's Interior Department was considering turning a significant portion of the Grand Canyon into a reservoir," Babbitt said. "This test is an appropriation symbol of a new way to manage our rivers." The test of BeachHabitat-Building BeachHabitat-Building Flows from Glen Canyon Dam through the Glen and Grand Canyon's commenced on Mar. 22. Following four initial days of steady flows at 8,000 cubic feet per second (cfs), the flows on Mar. 26 were increased to 45,000 cfs for a seven-day period to test the ability of a managed high flow, or flood, which will rebuild critical beaches along the Colorado River and restore backwater habitats critical to endangered fish. Periodic high flows such as those being tested are provided for in the Operation of Glen Canyon Dam Environmental Impact Statement which was completed in 1995. The flows also fit within the intent of the Grand Canyon Protection Act of 1992, which provides for operation of Glen Canyon Dam for environmental purposes in Glen and Grand Canyons in addition to traditional water and power generation benefits. To provide for this test, the 1996 Annual Operating Plan for the Colorado River, signed by Secretary Babbitt, contained terms and conditions for the releases. The Colorado River Basin States consulted with the Secretary, as did the public and special interests as provided in the Grand Canyon Protection Act. Secretary Babbitt pointed out that prior to the construction of Glen Canyon Dam, the Colorado River was a sediment-laden, dynamic river which fluctuated according to the seasons, rainfall, and inflows from side canyons. However, the construction of the dam altered the natural dynamics of the Colorado River, with resulting impacts to Glen and Grand Canyons. "It is critical that we develop management practices that will provide for the maintenance of the ecological health of the Grand Canyon. Through the Glen Canyon Dam EIS, we have been able to develop an understanding that the future of the sandbars and backwater habitats depends upon careful management of sand and the frequency and magnitude of flood releases from the darn. We are testing that hypothesis in the coming week," Babbitt said. Those flows are expected to redeposit sediment from the bottom of the river on the banks above the normal high water mark which has been limited to 20,000 cfs since August 1991, thus rebuilding the beaches. Also, the flows will serve I to scour the backwaters that have silted in and restore critical habitat for the humpback chub, an endangered fish. If the test of the flows proves to be productive, then the process will become available to resource managers in future years on an occasional basis. The full testing period will be between March 22 through April 7, 1996. Following four days of steady flows of 8,000 cfs, flows will increase starting during the night of March 25 at the rate of 4,000 cfs per hour (cfshr) until the level of 45,000 cfs is reached at about mid-day, March 26. The flows will be maintained at that level for seven days. On April 2, they will be decreased in a three-step three-step fashion to maximize sediment deposition. First, they will be reduced at a rate of 1,500 cfshr until 35,000 cfshr discharge is reached. The next step will be to reduce flows at the rate of 1,000 cfshr until a level of 20,000 cfshr is reached. The final reduction will then be at the rate of 500 cfshr until the flows reach 8,000 cfs, which will be in the morning of April 4. They will remain at 8,000 cfs through Sunday, April 7. Following that, the flows will return to normal operations under the current Interim Operating Criteria. The flows of 8,000 cfs before and after the high flows will allow baseline data to be obtained prior to and immediately after the high test flows. |