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<br />. <br /> <br />. <br /> <br />4t <br /> <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. 111e 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 1995. <br /> <br />PROGRESS ELEMENT i.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 beachlhabitaHuilding flow (BHBF) concluded that the 45.000 r;fs <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. <br /> <br />Timing, duration and magnitude of BHBFs, and effects on endangered species, are still subject <br />to speculation and rec;uire further tes1ing and validation. In addition to achieving anticipated <br />benefits to humpbac:( C.''\l.!b hai::~at, higher stage experimental BHBFs have been recommended <br />to test the precision of estimated stage-Ie-discharge relationships at terrestrial endangered <br />species sites, including Kanab ambe~nail habitat at Vaseys Paradise, and the four his10ric <br />southwes1em willow flycatcher nesting sites. <br /> <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 6.23 mafwateryear. 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] altemative. Progress is being made for planning for a <br />low flow, so that when an 8.23 maf release is projected, Reclamation can be prepared to <br />coordinate with the other participants in the AMP and implement the test flow. <br /> <br />. . <br />Reclamation accepted the Service's recommended RPA in an April 6, 1995 response to the 80.. <br />This letter of response indicated how Reclamation would implement the RPA. In this response. <br />Reclamation articulated that: <br /> <br />1) implementation of experimental flow are to be coordinated through the AMP; <br /> <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. <br /> <br />In 1997. Reclamation contracted with SWCA. Inc. Environmental Consultants, to summarize and <br />evaluate known in (ormation about native and non-native fishes in Glen and Grand Canyons. The <br /> <br />2 <br />