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Endangered Species - Generally the NPS desired flows would have a beneficial effect on endangered fish habitat peak flow needs. Under the base model run, flows requested for " endangered species were met or nearly met 33 percent of the time, for the remainder of the NPS desired flow runs analyzed, this percentage increases to 60 to 75 percent. Prior to filing any water right claim, this information needs to be carefully reviewed with the Fish and Wildlife Service. Recreation - As stated earlier, throughout most of the recreation season, elevations at Blue Mesa reservoir would be reduced by 2 to 3 feet. Generally, higher reservoir levels are more desirable for recreation, aesthetics, and fish production. Increased minimum flow periods in the National Park resulting from the NPS desired flows would allow more frequent river crossing, but overall no significant effect on recreation is expected. In the Gunnison Gorge, downstream of the Park, days with flows under 500 cfs would increase by approximately 25 percent and days with. flows above 5,000 cfs would approximately double, thereby reducing river related recreation due to safety concerns. Flooding - Under the NPS desired flow model runs, flooding due to icing upstream of the Aspinall Unit was not affected since the end of December target elevation was set as an operational parameter. Flooding downstream in the Delta area would continue to be a problem since the actual peak at Delta is a function of runoff timing and flows from other tributaries. Under NPS desired flow scenarios, the model results showed increased flooding potential in the Delta area when the May 1 forecast was in the upper 40 percent range and the actual runoff was the same or increased. Outside of these runoff parameters, there does not appear to be an issue with flooding in the Delta area. Compact - The effects of operating the Aspinall Unit to provide. NPS desired flows have not been analyzed for impact on Colorado's entitlement to its share of the Colorado River. Generally, operating criteria that reduce the frequency of filling Blue Mesa would reduce the 'potential for Colorado to develop water supplies. Conclusions and Recommendations Under current operating criteria, it is not possible to operate the Aspinall Unit to fully implement the proposed hydrograph criteria designed by the NPS to quantify the reserved water right for the Park. Requested spring peak flows above 10,000 cfs, when met, would only be due to unusual hydrologic conditions and not from intentional operation of the Aspinall Unit. Reclamation cannot meet the requested mid-range flows of approximately 6,500 - 10,000 cfs, with existing Aspinall Unit outlet facilities and current operating criteria. To intentionally operate the Aspinall Unit at higher reservoir levels to meet NPS peak flows would put the structural integrity of the dams at risk and increase the potential for flooding. Even partial implementation of the NPS proposed hydrograph criteria would result in impacts to the operation and purposes of the Aspinall Unit that are inconsistent with the intent of the 15