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<br />APPENDIX B <br /> <br />GLEN CANYON DAM 1997 AN~NUAL PLAN OF OPERATIONS <br />PREPARED IN ACCORDANCE WITH THE OPERATING CRITERIA <br />DEVELOPED FOR THE GRAND CANYON PROTECTION ACT <br /> <br />. <br /> <br />Under the most probable inflow conditions in water year 1997, Glen Canyon Dam is <br />expected to release about 14.1 million acre-feet through the Grand Canyon to Lake Mead. <br />1bis is about 5.9 million acre-feet greater than the minimum objective release and is the <br />result of high snowpack conditions throughout the Colorado River Basin. Lake Powell is <br />expected to fill in July. <br /> <br />Monthly release volumes from Glen Canyon Dam during 1997 are expected to range from <br />600,000 acre-feet to 1,500,000 acre-feet. Projected allowable fluctuations therefore will be <br />6,000 cfs or 8,000 cfs (see criteria). With projected monthly release volumes, it is likely that <br />peak daily releases will exceed 20,000 cfs during the months of February through July, when <br />monthly release volumes are at their highest for the year. Minimum releases of 5,000 cfslhr <br />decreasing will be followed. All of the above is outlined in the Record of Decision <br />implementing the preferred alternative of the GCDEIS. <br /> <br />With projected monthly release volumes, it is likely that peak daily releases will exceed <br />..,~ .20,600 cfs during the months of Febrwuy through July, when monthly release volumes are at <br />.. their highest for the year. Releases above 25,000 cfs will be made as steady flows. Since <br />. . ,"there are concerns for possible modifications of the environmental restoration in the Grand . <br />Canyon accomplished last year with the beachlhabitat-building flow, monitoring of the . ) <br />impacts of this spring's releases will be an important objective of the Grand Canyon <br />. Monitoring and Research Center and may result in fluctuating flows to aid in this effort. <br /> <br />Every measure will be taken to prevent a powerplant bypass this spring in order to preserve <br />the environmental enhancement accomplished by the beach/habitat-building test flow <br />conducted in March 1996. Water year 1997 had a January 1,1997, Lake Powell storage <br />content greater than 19 million acre-feet; therefore a habitat maintenance flow of powerplant <br />capacity is not planned. <br /> <br />1bis plan is prepared in conformance with section 1804(c)(I)(A) of the Grand Canyon <br />Protection Act. Any changes to the plan would require reconsultation in accordance with this <br />Act. <br /> <br />. <br />.~) <br />