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from Flaming Gorge would be required to achieve the Reach 2 flow recommendation peak and duration targets. In these years, the objective would be to achieve targeted flows in Reach 2 of 18,600 cfs for 2 weeks. To conserve water, bypass releases in these average years would be made only to the extent necessary to achieve this target. It can be expected that bypass releases, when required to meet the 2000 Flow and Temperature Recommendations in average years, would be implemented for a period of less than 2 weeks. In some years classified as average, the targets achieved during the spring would be moderately wet or wet as a result of flows on the Yampa River that exceeded forecasted levels. The objective in dry and moderately dry years would be to conserve reservoir storage while meeting the desired peak flow targets in Reach 2 as specified in the 2000 Flow and Temperature Recommendations. The bypass tubes and the spillway would not be used to meet flow targets in moderately dry and dry years but, on rare occasion, might be needed to supplement flows that cannot be released through the powerplant because of maintenance requirements. In dry years, a powerplant capacity release of 1 day to 1 week would occur during the spring, and this release would be timed with the peak of the Yampa River. In moderately dry years, a 1- to 2-week powerplant capacity release would occur during the spring and would be timed with the peak and post peak of the Yampa River. 5.13.3.2 Use of Bypass Tubes and Spillway at Flaming Gorge Dam The bypass tubes and the spillway at Flaming Gorge Dam have been utilized historically, as needed, for safe operation of the dam. In years with high inflow, bypass releases, and sometimes spillway releases, may be required under the Action Alternative to meet the 2000 Flow and Temperature Recommendations. Bypass and spillway releases, required for safe operation of the dam and to meet the 2000 Flow and Temperature Recommendations, would be scheduled coincident with Yampa River peak and post peak flow (the mid-May to mid-June time period) with the objective of meeting flow recommendation targets in Reach 2. There would be some years (moderately wet years and average years) when use of the bypass would not be required for safe operation but would be needed to meet the 2000 Flow and Temperature Recommendations. As part of the annual planning process discussed above, Reclamation would consult with the U.S. Fish and Wildlife Service and Western and coordinate with the Technical Working Group to make a determination whether bypasses should be attempted to achieve the targeted Reach 2 magnitudes and durations. S.13.3.3 Operations in August Through February (Base Flow Period) Under the Action Alternative, during the base flow period, Reclamation would classify the current hydrology of the Green River system into one of the five hydrologic classifications described in the 2000 Flow and Temperature Recommendations (wet, moderately wet, average, moderately dry, and dry). For the month of August, the hydrologic classification would be based on the volume of unregulated inflow during the spring period. For the months of September through February, the percentage exceedance would be based on the previous month's volume of unregulated inflow. If the unregulated inflow during the previous month falls into a different hydrology S-26 4 Operation of Flaming Gorge Dam Draft EIS