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<br />Compact - The effects of operating the Aspinall Unit to provide flow recommendations have not been <br />analyzed for impact on Colorado's entitlement to its share of the Colorado River. Generally, the <br />recommended t10ws reduce the frequency of filling Blue Mesa and would reduce the potential for <br />Colorado to develop water supplies. <br /> <br />Conclusions and Recommendations <br /> <br />Under current operating criteria and forecasting methods used in the modeling (including estimates of <br />tributary flow), draft flow recommendations ate not fully met. However, modeling results show <br />recommended peaks, base flows, and minimum fish passage flows can be met more frequently. <br />Operating for flow recommendations impacts storage levels in Blue Mesa which would reduce the <br />dependable yield of the reservoir for Colorado uses and reservoir related fisheries and recreation. <br />Downstream flooding could increase under the flow recommendations but other downstream resources <br />such as recreation and fisheries would be protected to a reasonable degree. To intentionally operate the <br />Aspinall Unit outside existing criteria, in certain instances, could put the structural integrity of the dams <br />at risk and increase the potential for flooding. <br /> <br />Operating criteria would need to be adjusted and storage releases increased to more fully meet the flow <br />recommendations. Structural modifications, including additional outlet works, could be required to <br />safely operate the Aspinall Unit facilities to meet flow flow recommendations at the frequencies <br />recommended for the endangered fish. <br /> <br />Reclamation plans to complete an EIS on alternative operations to help meet the endangered fish <br />recommendations when the recommendations are finalized. The existing model to analyze the flows will <br />be upgraded and integrated with State resources to assess impacts to other water users in this process. <br />Reclamation should work with the FWS to refine criteria to better meet flow recommendations and <br />reduce impacts. Impacts of operations on various resources should be addressed through negotiations, <br />the reserved right quantification process, and in the NEP A process. An important decision, to be made in <br />cooperation with Colorado, is needed on how much of the Aspinall Unit water yield can be impacted to <br />meet flow recommendations. <br /> <br />17 <br />