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c <br />With current operation criteria and restrictions, NPS desired peaks of approximately 6,500 cfs or <br />less can partially be met. Desired flows above 10,000 cfs, when met, would generally be met due <br />to unusual hydrologic conditions and not from intentional operation of the Aspinall Unit to meet <br />NPS desired flow scenarios. Reclamation cannot meet the requested mid-range flows of <br />approximately 6,500 to 10,000 cfs with Aspinall Unit facilities and current operation criteria. <br />Intentionally operating the Aspinall Unit at higher reservoir levels to meet NPS peak flows would <br />put the structural integrity of the dams at risk and increase the potential for flooding. <br />Even partially meeting the NPS desired flows would result in impacts to the operation and <br />purposes of the Aspinall Unit that are inconsistent with the intent of the authorizing legislation. <br />Impacts to purposes such as generation of hydroelectric power, downstream flood protection, <br />recreation, Compact development, and fish and wildlife enhancement are discussed in this report. <br />Operating the Aspinall Unit to fully meet the NPS flow goals would increase these impacts. This <br />report does not evaluate impacts on other water supplies, water rights, or diversion structures. <br />Impacts of attempting to meet the NPS desired flows include: <br />- foregone hydroelectric power of $5 to $11 million annually <br />- loss of emergency response to power needs <br />- increased operation and maintenance cost due to increased spillway and bypass use <br />- impacts to reservoir fishery and recreation due to reduced reservoir levels <br />- benefits to downstream endangered fish species <br />- potential impacts to Gold Medal trout fishery with increased frequency of minimum flows <br />- increased risk of downstream flooding <br />- reduced reservoir yield with possible impacts on Compact use <br />Structural modifications, including additional outlet works at the three dams, would be required <br />to safely operate the Aspinall Unit facilities to meet flows greater than 6,500 cfs at the <br />frequencies desired by the NPS. Operating criteria would also need to be adjusted to more fully <br />meet the NPS desired flows. Meeting the NPS flow goals would significantly impact Aspinall <br />Unit purposes and analyzing this would involve a major commitment of resources, National <br />Environmental Policy Act compliance, and possibly additional Congressional authority to <br />implement. <br />The reserved right quantification can have significant impacts on Colorado resources and <br />interests, but public and agency coordination on the reserved water right process has been <br />limited. The Department of Justice has made commitments to share information with the public. <br />At a minimum, Reclamation strongly recommends that model results and associated reports be <br />reviewed with appropriate state and local agencies prior to the filing of any water right claim. <br />IV