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-3- Operational criteria (water storage levels), together with run-off forecasts, dictate the flow release patterns for the Dolores River downstream from McPhee Dam. These criteria call for a constant (year-round) minimum flow during non-spill periods. A "dry year" minimum flow calls for 20 cfs, an "average year" 50 cfs, and a "wet year" 78 cfs. Under full project development, the current operational criteria allocate 25,400 AF of water for "fishery and aesthetic purposes" downstream of the dam. Early in 1990, "dry year" conditions were declared and a 20 cfs release pattern was implemented in early March and continued into mid-June 1990. However, concern over impacts of a 20 cfs flow prompted the USBOR-DPO to increase the flow to 50 cfs in mid-June 1990, to minimize losses in the tailrace trout fishery. Later that year the USBOR-DPO proposed replacing the year-round constant minimum flow regime with seasonal minimum flows. This proposal called for lower flows in winter and slightly higher flows during summer, to minimize potential thermal stress problems during the summer. An "Interim Operating Agreement" designated a pool of 30,100 AF of water for "fish releases" (on an annual basis). The pattern of release from the 30,100 AF pool was to be determined by a fishery advisory committee, with representatives from the USBOR, U.S. Forest Service, BLM, CDOW, U.S. Fish and Wildlife Service, and Trout Unlimited. The best use of the 30,100 AF of water appeared to be a fall to spring release of approximately 30 cfs and a spring to late-summer flow of approximately 65 cfs. This flow regime has been in effect (during non-spill periods) for the most part since October 1990. In November 1990, the USBOR-DPO committed to a 3-yearstudy of the Dolores Project. In a document entitled "Dolores Project Resources Optimization Study" (U.S. Bureau of Reclamation- Durango Projects Office, November 1990), the agency recognized that: "Operation of the project as directed by the Definite Plan Report (DPR) and the Final Environmental Statement (PES) may not be optimizing the project's resources. This study will explore opportunities for enhancement, and develop operational or structural alternatives to enhance the total resources of the project." A major portion of this study called for an evaluation of the fish and wildlife resources affected by the Dolores Project. In Chapter V (Evaluations of Alternatives) of the "Dolores Project Resources Optimization Study," the USBOR-DPO recognized that the trout fishery below McPhee Dam had generated "intense interest". Therefore, the agency agreed "an intense effort will be made to evaluate this resource under both baseline conditions and under the conditions of any alternatives.," The "Dolores Project Resources Optimization Study" document committed USBOR-DPO to nine different specific study objectives that pertained to the fishery resources. Objectives 2, 5, and 6 provide specific guidelines and direction for that study. Objective 2 was "Monitor river and air temperatures throughout the year to determine the relationship of water temperature to air temperature for different flows at various locations on the river." Further, "This information will be used to determine minimum seasonal flow requirements to provide acceptable trout habitat." Objective 5 was to "Provide constant releases seasonally to determine the requirements for successful trout spawning. Measure success through subsequent fish sampling." Objective 6 was to "Conduct fall and spring fish sampling to determine changes in population structure and,the relative quality (size and condition) of the fishery. "