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JUN- 8-90 FRI 16:23 D_ o . p . U.C . REG ION P_02 .. </ .' " .~ ~..' ~ ~ DRAFT (E Mailed to HMorgan) &.R~ ~/8/fO Dolores Pro1ect McPhee Dam - Minimum fisherv flows Emernncv Plan Situation: The present release of 20 cfs may be insufficient to maintain the trout fishery below McPhee Dam due to water temperature increases through the summer months. Current Stat~: Minimum flows were reduced from 78 cfs to 20 cfs in early March 1990 ill accordance with the operating criteria and the Final Environmental Impact Statement. Concerns have been raised .s v ""'ct' at the,," flow levels the water temperature will eventually become lethal t~ !t'out and the fishery will be destroyed. Extensive temperature monitoring has been set up from the Dam to approximately 50 miles downstream. Pourteen sites are monitoring water temperature every 5 minutes. These sites can be evaluated daily, if found to be necessary. The present temperature of releases from the Dam are 45 degrees. At approximately 5 miles downstream, temperatures are fluctuating to a high of 70-71 degrees but for only 5-15 minutes each day. Research data seems to indicate that 7S degree water with several hours duration could be lethal. ~ater temperlltures do not seem to warm substantially further downstream. Temperatures will most likely continue to rise as the averale nighttime temperature increases. Present thinking is that the present situation is t<; & crisis, but requires close monitoring. Two to 3 weeks may be required to reach critical temperature. Action Plan: 1. Bureau of Reclamation (Durango Projects Office) monitor temperatures sites da11y. 2. estimate releases Bureau of Reclamation (Durango Projects Office) evaluate trends temperature "critical point" daily to determine when increased may be required.. and 3. Decision to increase releases rests with the Project Manager, Durango Projects Office after notification of the Commission and the Regional Director. Releases will be initiated when the ~aximum water temperature exceeds 70 degrees for more than 1 hour. 4. Prior to releases, notify the District, Colorado ~ater Conservancy Board, and Trout Unlimited. ~ Pw",,"- 1 w.-<U.i.f . 5. Increased flows in increments of 10 cfs (24-hour travel time) and monitor temperature performance.