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002404 DRAFT 6/4/01 Minority Issues and Fish and Wildlife Service Recommendations Regarding the Service's Gunnison/Colorado River Flow Recommendations Attendees at April 30, 2001 meeting in Grand Junction: Tom Pitts Ray Tenney Bill Davis Bob Muth Clayton Palmer Gerry Roehm Frank Pfeifer Kirk LaGory George Smith Chuck McAda Shane Collins Randy Seaholm Michelle Garrison TECHNICAL ISSUES 1) Approaches for developing peak-flow recommendations to restore and maintain required in-channel habitats. Justification for recommended peak-flow thresholds. Minority proposal: if the Service can explain why, biologically or physically, for expanding upon the data/recommendations made by Pitlick and Milhous; they should do so in the goals and then a technical team representing Recovery Program participants should be formed to review those justifications and have further biological/physical discussions. Service recommendation: Neither Pitlick nor Milhous made specific flow recommendations for the recovery of endangered fish, The Service based its flows recommendation on this data, as well as other geomorphological data, in the context of the biological requirements of the fishes, While Pitlick based his flow estimates on Y2 bankfull (initial motion) and bankfull flows (significant motion) in 50% of his transects, the Service believes that the endangered fish need flows sufficient to achieve significant motion throughout more than 50% of the available habitat at some frequency (i.e., 80% of the habitat, 10% of the time) and some significant motion 70% of the time. The Service's flow recommendations have been reviewed and are supported by Dr. Pitlick and other geomorphologists through a peer-review process, The Service has reviewed its data and found that flows in the Gunnison River exceeded 20,000 cfs in 3 of 5 years in the wettest hydrologic category. Nevertheless, following the discussion and considering the rationale provided by the minority reports, the 1