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<br />-' <br /> <br />-. - <br />- -- <br />.- <br /> <br />, Water rcle"ses will be made by the DWCD under tli",ction from Reclam"tion and in eoordi""tion with <br />uther federal and sw(e agencies and local ill/crests for /ish .1tld wildlife purposes downslrcam of McPhee <br />Dam. <br /> <br />, No deducti~n would occur from the int,'rim pool nt "ny time R,'c1amation directs" splil n'\e:lSe fr~1tI <br />McPhee Reservoir. <br /> <br />. The interim m:umged pool would be subject to reduction due to shortages occulTing to other Project <br />water users. <br /> <br />Reclamation established a Biology Committee comprised of representatives of Reclamation. CDOW, <br />USF&WS, USFS. BLM and Trout Unlimited (TU). The CDOW assumed chairmanship of the Biology <br />Committee. The Committee meets intermittently to review the status of the Dolores River fishery, review water <br />release forecasts from McPhee Reservoir, develop recommended water releases from the reservoir using the <br />interim pool and recol\1mend biological study needs. <br /> <br />Figures 3 and 4 depict water releases from McPhee Reservoir in 1990 (using the DPRlFES water release <br />criteria) and releases from 1991 to 1993 (using the interim managed pool). Please note that periods of spills are <br />indicated in a darker shade. Figure 4 shows that the interim managed pool allowed releases to the Dolores River <br />to be maintained in the 60-to-70 cfs range during the critical summer months, and at 30 cfs or higher during the <br />winter. <br /> <br />In addition, Reclamation contracted with CDOW to conduct biclogical studies of the Dolores River <br />downstream from McPhee Darn to study the effects cf interim operation and develop recommendations for long- <br />term operation of the reservoir. <br /> <br />F. DISCREPANCY IN PROJECT OPERATION STUDY <br /> <br />In addition. Reclamation reviewed the Project's operation study used for the 1977 DPRlFES. The water <br />release criteria were originally established from an operation study model used to estimate inflow and outflow <br />from McPhee Reservoir on a monthly basis for the years 1928-1973. The study result from'.the model showed <br />that during 28% of this 46-year study period, average minimum flows of 78 cfs would have occurred (so-called <br />"wet" years); fifty percent of the time these flows would have amounted to 50 cfs (so-called "normal" years); and <br />22% of the lime, the flows would have been 20 cfs (so-called "dry" years). <br /> <br />The operation study model did not simulate managed waler releases (as the dam is really operated) but <br />allowed the reservoir to fill and spill in an uncontrolled manner. This resulted in the model showing shorter spill <br />periods with higher flows than actually happens. As a result, the operation study did r.at simulate releases of 78 <br />cfs during "wet" years, but released 50 cfs and assumed the extra water needed for the nigher flows would be <br />offset by the longer periods of managed spills (longer periods when no project water was required to be released <br />downstream). This assumption was not valid. as spills occur only during a very short, late spring period (see <br />page 31, Appendix B, 1977 FES), and resulted in a discrepancy of 3,900 AF (25,400 AF vs. 29,300 AF) in the <br />volume of Project water needed to satisfy the DPRlFES release criteria. <br /> <br />G. SCOPE OF PROPOSAL AND THIS DOCUMENT <br /> <br />The scope of this EA is limited to two proposed actions: (1) the proposal to modify the operation of <br />McPhee Reservoir for release of water to the Dolores River for fish and wildlife purposes and (2) the proposal to <br />acquire additional water for release from McPhee Reservoir to the Dolores' River to benefit fish and wildlife <br />resources. Reclamation will use this EA to determine whether 10 prepare an Environmenrallmpaa Statement <br />(EIS) or a Finding of No Significant Impact (FONSI). If the environmental analysis indicates that the <br />environmenral consequences do not have a significant impact on the human environment, a FONSI will be <br />prepared. If the EA indicates that the proposed action constitutes a major federal action having a significant <br />impact on lite quality of the human environment. then a Notice of Inlent to prepare an E1S will be prepared and <br />publhhed in the Federalllefl,wer. <br /> <br />8 <br />