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001933 Lake Powell will be operated as follows: 8) Lake Powell will follow a forecast driven, spring runoff operation (January through July) that attempts to fill Lake Powell to a July target storage (23.822 mafor 500 kafof space) and a fall operation (August through December) that attempts to draw down the reservoir to a December target storage (21.900 maf or 2.422 kaf of space). Lake Powell's spring and fall operational release is constrained in each month to be within a minimum and maximum range. The range is set to 390 kaf per month and 1500 kaf per month respectively, reflecting the current limits on release rates of 6500 cfs and 25000 cfs. 9) Lake Powell's operation will satisfy a minimum objective release to the Lower Basin of 8.23 maf over each water year (October through September) if those releases do not result in Powell's elevation being below 3370 feet (top of dead pool). At times when Lake Powell does not have enough water to meet the minimum objective release, a mass balance will be used to determine how much water is released (inflow plus water in storage above dead pool minus losses). 10) Lake Powell will make equalization releases (in excess of the mmtmum objective release) if the end-of-water-year (EOWY) content in Lake Powell is forecasted to be greater than Lake Mead's EOWY content and the 602(a) storage criterion is met. The 602(a) storage value will be computed as documented in the SIA-FEIS, with the addition that no equalization will occur for the years up to and including 2016 if Lake Powell is projected to be below 14.85 maf (elevation 3630 feet) on September 30, per the Final Environmental Assessment Adoption of an Interim 602(a) Storage Guideline. II) Beach/Habitat Building Flows (BHBF) are triggered as documented in the SIA-FEIS. Note: These assumptions are identical to those used in the SIA-FEIS and the Colorado River Interim Surplus Criteria Final Environmental Impact Statement (ISG-FEIS), as documented in Volume U, Attachment J of the ISG-FEIS, with the following exceptions: . In those studies, the minimum objective release was maintained if those releases did not result in Lake Powell's elevation being below 3490 feet (minimum power pool). However, when the minimum objective release resulted in Lake Powell going below minimum power pool of elevation 3490 feet, releases from Lake Powell were adjusted in order to protect the minimum power pool. . The interim 602(a) storage criterion involving Lake Powell's elevation of 3630 feet was not used in those studies. Lake Mead will be operated as follows: 12) Lake Mead will operate to meet downstream demand, except when additional releases are necessary to meet the Corps of Engineers flood control procedures. Draft: Subject to Change 2 Last Revisiou: May 13,2004