Agenda Item 17: Water Supply Protection - Colorado River 7-State Agreement Approval

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January 23 -24, 2007 Board Meeting Agenda Item 17 Page 3 of 6 Coordinated Operations of Powell and Mead under Low Reservoir Conditions: Under the current Long -Range Operating Criteria for Colorado River Reservoirs, Lake Powell and Lake Mead equalize storage whenever Powell storage is greater than storage in Lake Mead so long as Powell is above the 602(a) storage level. The 602(a) storage level is the volume of water deemed necessary in Lake Powell, Flaming Gorge, Aspinall, and Navajo to assure to the extent possible that the Upper Basin can sustain its current level of development without having to curtail uses so that during a drought the Lower Basin receives the water apportioned to it. The current 602(a) storage requirement is elevation 3630 or approximately 14.85 MAF. When Powell is below the 602(a) level, operations at Glen Canyon Dam seek to maintain a minimum objective release of 8.23 MAF (7.5 MAF per year plus one -half of the 1.5 MAF delivery obligation to Mexico, the latter condition to which the Upper Basin strongly disagrees with). The result is that Lake Powell absorbs the impact of the drought at the beginning and Lake Mead absorbs the drought impacts on the tail end until Powell has recovered to the 602(a) storage level. Under the proposed adjustment to the criteria when the reservoirs reach certain reduced levels of storage, they would be operated in a manner that keeps the amount of storage in the two reservoirs approximately equal and the Lower Basin would begin to take shortages. The range of release would be expanded in order to provide the flexibility to achieve this objective, which is beneficial to the Upper Basin. A diagram and brief description of the States proposal for the coordinated • operations of Lakes Powell and Mead under low reservoir conditions is attached. Improved System Efficiency and Management: The Lower Basin is evaluating a number of system improvements and management strategies to improve the efficiency of their operations. The Upper Basin has been adamant that these improvements remain in the Lower Basin and that the Lower Basin does not seek these types of improvements in the Upper Basin because the Upper Basin is relying on these types of improvements in the future for its own benefit. The Lower Basin towards this end is looking at canal linings, additional storage such as that along the All- American Canal (Drop 2 reservoir), and "Intentionally Created Surplus" or ICS accounts in Lake Mead. We would note that Lake Mead has previously never had any storage accounts, rather Lower Basin water users have submitted water orders to Reclamation and deliveries have been made to them in accord with the Compacts and their contract terms. The Lower Basin is also developing groundwater banks, mostly in Arizona, where a states unused apportionment can be banked and recovered at a later date. A number of forbearance and other agreements are required to achieve this objective, some of which are already in place. Augmentation of Colorado River Supplies: The Southern Nevada Water Authority, pursuant to the terms of the proposed 7 -State Agreement, is funding a basinwide augmentation study that is looking at all potential augmentation sources. Representatives from each of the 7- States are serving on an advisory committee for the study effort (Rod Kuharich and Randy Seaholm are serving in that capacity for Colorado). The study is focused on vegetative management, desalination of brackish