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Agenda item J 5 September 13-14,2005 Board Meeting Page 2 of5 about what might happen absent a united 7-State position. In the end. California and Nevada worked out their differences and all 7-states agreed to sign the letter. . The letter outlined a three pronged approach; conjunctive management of Lakes Powell and Mead under low reservoir conditions done in concert with Lower Basin shortage criteria. system efficiency improvements. and Colorado River Water supply augmentation. The letter was sent to Reclamation by the August 31st deadline. We hope to have a signed copy of the letter available to attach. ifnot we will provide it at the Board meeting. 7-State Technical Workgroup Model Runs Early model runs demonstrated that there are several ways to maintain more storage in Lake POYo'ell during low reservoir conditions and reduce the magnitude and frequency of shortages to the Lower Basin. The model runs also show that based on the historic record to date and current operations pursuant to the Coordinated Long-Range Operating Criteria that there is virtually no chance that the Upper Basin will fail to meet the 75 in I 0 requirement in the compact. Furthermore, there is only about 10% chance that Lake Powell would fall below minimum power pool elevation (3490). The runs show that there are some reasonable ways to reduce the 10% chance of going below minimum power pool elevation at Powell down to I or 2%. but no way to totally eliminate it simply because of adverse hydrology. which in combination with some minor Upper Basin development over the nexl 10-20 years just leaves the system short. Certain options benefiting Lake Powell could be implemented without any signi ficant hann to the Lower Basin. but given the premise that there must be some benefit to both basins, would not be implemented. . The second round of model runs are briefly discussed it the attached Power Point presentation. The seven additional model runs compare alternative operations to the existing Coordinated Long-Range Operating Criteria (Lake Powell Nonnal). These model runs fall into two categories. those that define releases at critical operating elevations in Powell. which sometimes arc associated with critical operating elevations in Mead. and runs that seek to simply balance contents between Powell and Mead when critical elevations at either Powell or Mead are reached. The Technical Group agreed that "TieredReIJev." and "002Jevl" should be pursued further. "TiercdReIJevl" is a targeted approach proposed by the Upper Basin. "002 rev I" is a content balancing approach proposed by the Lower Basin. These two model runs have the greatest potential for further refinements that would provide benefits to both basins and do so in a fairly equitable fashion. The Technical Group will meet on September ih in Phoenix to further refine those two model runs. Once those runs have been further refined. different Lower Basin shortage strategies can be developed and evaluated. including some that incorporate certain levels of Lower Basin conservation before critical elc\.ations that cause implementation of shortage critcria are necessary. The one thing that is becoming incrcasingly clear is that operations that benefit both basins under low reservoir conditions can be developed. If a particular low reservoir operation is agreed too and hydrologic conditions Warrant. such would be tested on an interim basis al least through 2016 and if found to be acceptable. could ultimately result in some changes to the Coordinated Long-Range Operating Criteria. Next StcPs . Ao(.,j Protl'l:bon . W,Uer PrOJect P1anrnng and Fin.mce. SIn>dm and Ldk... Prott'Ction Wdlt'JSupply ProI[,.-tiQn. Consen.'dOon PLmrnng