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, -' ~t e 002171 e releases were reduced to 31 cfs until October 3]. ] 990. An interim operation agreement for operation of McPhee Dam from November I, 1990 through October 31. 1993 (subsequently extended through the present) was executed between Reclamation 8.Dd the DWCD. Toe interim agreement provided for alternative dam operation until a long-term solution to the water release and trout fishery issue could be developed and implemented. From November I, 1990, to the present. McPhee Reservoir has been operated according to the Interim McPhee Dam and Reservoir Operations Afreement (lOA), as amended. Key elements of the current lOA related to water releases for fISh and wildlife purposes to tbe Dolores River are: · .A.o interim pool of up to 29.300 AF available for release each water year (November 1 to October 31). The 29,300 AF volume is comprised of: ~l) 25,400 ~ reserved for fisb and wildlife purposes; (2) up to. 3.900 AF of senior downstream water rights. (After October 31, 1993, 809 AF of Wale!; reserved for Totten Reservoir and included in previous versions of the lOA w~ not available for downstream release.) · Water releases will be made by the DWCD under direction from Reclamation and in coordination with other federal and state agencies and local interests for fish and wildlife purposes downstream of McPhee Dam. · No deduction would oceUi from the interim pool at any time Reclamation directs a spill release from)' McPhee Reservoir. · The interim managed pool would not share shortages occurring to Project irrigation water users. Figures :3 and 4 depict water reieases from McPhee Reservoii in 1990 (using the DPRJFES water release criteria) and reieases from] 991 through Octooer 1995 (using the interim managed pool). Note that periods of spills are indicated in.e. darKer shade. Figure'; shows tha: the interim managed pool aliowed reie.e.ses to tne Dolores River 10 be maintained in the 60 to 70 cfs range or higher during tile criti::al summer months, and a: 30 cfs or higrier during the winter. Si.T'Jce late 1990. Redamation has been coordinating with Project water users, Iro..: unlimited, CDOW. the LS. Fish and Wildlife Service (l!SF&W5), the Bureau 0: Land Management (B~M), the L: .S. rores: Service (USFS) anci othei i.nterested individuals and groups to identify a long-ten....l solution. A Biology Comminee comprised of representatives from Reclamation. CDOW, USF&WS, USFS. EI...M and Trout Uniimited (TU) was estabiished to administer the pool of water reserved for downstream use and to r~ommend biologicai studies to determine the fiow r~iremems for a coldwater fishery'. R~iamation, cno\\'. and tile lJSFS cOnCucted the smciies. Reclamation also reviewed the Proj~t hydrology a..."'l.d the 1977 Project operation study use.:i to evaiuate the Proje<:: watei supply and to allocate Project water. Tnis review reveaj~ a ciiscreparlcy j., the volume of Project water reserved by the united States for dov..ostream fish and wildlife purposes ami the IIcrual volume of Project water that would be r~ired to meet the downstream DPRJFES reiease criteria. Tne 1977 Project operation study simul/ltes Project operation on Ii monthly basis for tne period 1928 through 19;3. During the scudy period. the minimum rei=e from McPhee Dam was is cfs in 13 years (28%), 50 cfs in 23 years (50%). and 20 cfs in lO years (22%). These reiCHses were made up of spills (water excess to the Project), water released to satis4'y senior dO.....'I1Stream water rights. and Project water rdeased from storage. The study indicated that the average annual amount of Project water required to be released from storage to make these flows was 25,400 AF. Because the operation sruriy isa monthly model, it is not possible to simulate managed releases in place of spills. The model allows tbe reservoir to fUl and spill in an uncontrolled manner. This results in much shoner spill periods with higher flows than would occur in actual operation. To compensate, the model did not simulate releases of 78 cfs during wet years but released 50 cfs dUrLT)g both normal and wet years and assumed the extra water needed for the higher flows would be offset by the longei periods 0:- managed releases in place of spills (ionger periods when no f Project water was required to be relt:asc:d from storage:;. however. this assumption is probabiy nOl vaiie. \\-nen .. Ininimum releases down5tres.rrJ were ir.::reas.::C irom 50 cfs to 7S cfs dU~~'1g we: years, toe average a:mua! volume of Project W/ller n:quiree to meet the dO"-TlSlrelm: cr1!er1!; was ir.::reast:d to 29.3Cwj AF. ;rus results in a discre!'flDcy of 3.900 .A..F betv..'een tht' VOlume of Pro.ieci v."at~:- r=s=;v~ by :b= Lr.it=-d Stares fa:- C0\1.'"iJ.S:rC2.m pu~ses aa~ tb::- ....olume of Project wate~ re'!ulTee l(. meet the D?RiF=.S GO\\'TlS{ream release cmen<i.