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<br />I <br />I <br />I <br />I <br />I <br />I <br /> <br />In 1994, the Fish and Wildlife Service issued a Biological Opinion on the Operation of Glen <br />Canyon Dam. One of the elements of the reasonable and prudent alternative in the Biological <br />Opinion is a "program of experimental flows. . . to include high steady flows in the spring and <br />low steady flows in the summer and fall during low water years (releases of approximately 8.23 <br />MAF)." This 10,152 MCM (8.23 ~1AF) release volume is the minimum release objective of the <br />Operating Criteria. <br /> <br />Since issuance of the Biological Opinion, hydrologic conditions have caused releases from Glen <br />Canyon Dam to exceed the minimum release objective and this experimental flow program has <br />not been initiated. <br /> <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br /> <br />The January inflow forecast for April through July unregulated inflow to Lake Powell was for <br />4,942 MCM (4.0 MAF) which is only 52 percent of average. Under this forecast, scheduled <br />releases from Lake Powell in water year 2000 were 10,300 MCM (8.3 MAF). Planning for the <br />implementation of experimental flows began at this time. January, February, and March, however, <br />were months with moderately above average precipitation in the Colorado River Basin. <br />Forecasted inflow stayed below average but increased from 52 percent of average in January to <br />78 percent of average in March, resulting in planned water year releases of about 11,600 MCM <br />(9.40 MAF), as required under the equalization criterion. However, because initial releases in <br />water year 2000 were above the minimum release objective, releases for the remainder of water <br />year 2000 closely resembled a minimum release objective pattern and Reclamation continued with <br />the planning for a test release. This test release proposal was called low steady summer flows <br />(LSSF). <br /> <br />The LSSF test releases were begun in April. From April through ~1ay, "ponding" releasesof382 <br />cms (13,500 cfs) or higher were made. A 4-day powerplant capacity release of approximately <br />850 cms (30,000 cfs), as pan of the test releases, was made from t>.1ay 3 through May 5, as well. <br />Releases in June, July, August, and most of September were 227 cms (8,000 cfs). <br /> <br />I <br /> <br />Even though 2000 was not a minimum release objective year, Reclamation executed the LSSF <br />test release pattern because the unusual hydrologic conditions required release volumes in the <br />second half of water year 2000 to be similar to those seen in a minimum objective release year. <br />Knowledge will be gained about the effect of such releases on the endangered humpback chub <br />and other native fish, and better prepare Reclamation to pursue the element of the reasonable and <br />prudent alternative under minimum release objective conditions. Conducting this experiment was <br />consistent with Reclamation's plan to implement the elements of the reasonable and prudent <br />alternative in the Biological Opinion. <br /> <br />I <br />I <br />I <br /> <br />During water year 200 I, releases greater than the minimum release objective of 10,152 MCM <br />(8.230 l\.1AF) will likely be made to avoid anticipated spills and/or to equalize the storage between <br />Lakes Powell and Mead. Under the most probable inflow conditions, releases of 11,600 t>.1CM <br />(9.40 t>.tAF) will be made, while under the probable ma'(imum inflow scenario, approximately <br />17,400 MCM (14.1 MAF) will be released. Releases above powerplant capacity are possible in <br />200 I. Such releases would be made consistent with the 1956 Colorado River Storage Project Act, <br /> <br />November 16, 2000 <br /> <br />11 <br /> <br />I <br />