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<br />ELEMENT 1.A
<br />Carry out a program of experimental flows, including high steady flows in the spring and low
<br />steady flows in summer and fall during low water years. The RPA set forth a schedule for
<br />development and implementation of low flows. Design of experimental flows and associated
<br />studies were to be completed by October 1996. Unless the Service doubted the validity of the
<br />study design or the ability of the flow to contribute to removal of jeopardy, the flows were to be
<br />implemented in April 1997. The flows could begin even later in 1997, if good faith effort to make
<br />sufficient progress were demonstrated. Absent sufficient progress, flows were to be
<br />implemented in the spring of 1998.
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<br />PROGRESS ELEMENT 1.A.
<br />Although a release combining both high steady spring flows and low steady summer and fall
<br />flows has not been realized, test of a high spring flow was completed in March, 1996. Research
<br />during the 1996 experimental beach/habitat-building flow (BHBF) concluded that the 45,000 cfs
<br />stage had the effect of filling in some retum channels, thus reducing backwater numbers.
<br />Backwater numbers have also decreased since April 1996 due to deposition of sediment into the
<br />retum channel and erosion of higher elevation reattachment bars.
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<br />Timing, duration and magnitude of BHBFs, and effects on endangered species, are still subject
<br />to speculation and require further testing and validation. In addition to achieving anticipated
<br />benefits to humpback chub habitat, higher stage experimental BHBFs have been recommended
<br />to test the precision of estimated stage-ta-discharge relationships at terrestrial endangered
<br />species sites, including Kanab ambersnail habitat at Vaseys Paradise, and the four historic
<br />southwestern willow flycatcher nesting sites.
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<br />A low flow study design has not been done, and the low flows have not been implemented. Low
<br />steady flows were not implemented in 1998, as called for in the opinion, because the forecast
<br />did not predict an 8.23 maf water year. The opinion recognizes that during moderate and high
<br />release years, Reclamation shall operate Glen Canyon Dam aCCOrding to requirements of the
<br />Modified Low Fluctuating Flow (preferred) alternative. Progress is being made for planning for a
<br />low flow, so that when an 8.2:3 maf release is projected, Reclamation can be prepared to
<br />coordinate with the other participants in the AMP and implement the test flow.
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<br />Reclamation accepted the Service's recommended RPA in an April 6, 1995 response to the BO.
<br />This letter of response indicated how Reclamation would implement the RPA. In this response,
<br />Reclamation articulated that:
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<br />1) implementation of experimental flow are to be coordinated through the AMP;
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<br />2) the flow experiments will include scientifically based peer reviewed criteria to measure
<br />and evaluate their impacts on downstream resources; the research would be managed
<br />and administered through the GCMRC; and that appropriate staff and funding levels
<br />needed to be identified. This memorandum was distributed to all cooperating agencies
<br />and interested parties.
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<br />In 1997, Reclamation contracted with SWCA, Inc. Environmental Consultants, to summarize and
<br />evaluate known information about native and non-native fishes in Glen and Grand Canyons. The
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