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1567 required releases would be necessary to avoid foregoing West Slope imports after the Lake fills. Any water released to Lake Fork in excess of the minimum requiCl:menr is a loss of ener- gy generation at rhe Mr. Elbert Powerplam. In a year of normal spring runoff. releases from the upper reservoirs would be made in March and April such thar rhe entire Project stOrage capacity ofTutquoise Lake is evacuated. Releases in May and June. rhe heighr of the spring runoff, would be avoided because the emire safe channel capaci- ry of Lake Creek below Twin Lakes Dam is quire often needed during that time period for the required bypass of the native inflow to Twin Lakes. The native inflow to Twin Lakes includes native ~lows of Lake Fork and Halfmoon Creek divened through the Mr. Elbert Conduit, in addi- tion to the narive flow of Lake Creek. If ,he safe channel capacity belo- . Twin Lakes Dam is reached. [hen diversio .s of native water from Lake Fork and Halfmoon Creek would be reduced or discontinued and energy generation would be foregone. In a year of heavy spring runoff. these releases would scart in March and conrinue through May in order [0 evacuate the Project storage capacity of Twin Lakes in addition to thar of Turquoise Lake. Afrer all Project stOrage space is filled in the upper reservoirs. releases from Twin bkes Dam and. if necessary. Sugar!oaf Dam would be made to avoid foregoing imports of Project wacer /Tom the Wesc Slope. An unavoidable bypass of the Mr. Elbert Powerplant would occur in such ye:us. In a year of below average spring runoff. releases from the upper basin reservoirs would be discon- tinued before rhe end of April to avoid scoring more water in Pueblo Reservoir than is necessary. Any unnecessary storage of water in Pueblo Reservoir represents a risk of foregoing Wimer Wacer storage in the Reservoir in the following winter and spring. Unnecessary storage of Project water in Pueblo Reservoir also causes greater loss- es of ProjeCt water co evaporacion. The evapora' cion from Pueblo Reservoir is greacer than /Tom rhe upper reservoirs. The evacuation of water from the upper reservoirs could be limiced. in any kind of runoff year. by rhe lack of Projecc storage space in Pueblo Reservoir. The available space in Pueblo Reservoir does nor correlare co the runoff in any single year because Pueblo Reservoir is designed co hold mul- tiple years of wacer supply. Consecutive dry years draw me reservoir down and consecurive wet years fill ic up. After .the upper reservoirs fill in July. no release of Projecr warer would be made umil the Following March. The only exceprions would be direct rele:lSes of imported water in a heavy n.moff year, and releases for Project wacer demands down- scream of Pueblo Reservoir in the evem thar all Project wacer is depleced from Pueblo Reservoir. Delaying any further releases umil March allows the upper reservoirs co remain as full as possible. This reduces evaporacion losses and. as a side ben- efit, enhances Rarw"J.rer .recreacion at the reservoirs. B. Baseline Arkansas River Hydrograph Incorporating Fryingpan- Arkansas Project Operations The following baseline Arkansas River hydro- graph was developed by using flows and Project operarions chac were observed from 1982 rhrough 1995. Projecc operacions thac were designed co fulfill flow managemenr recommendacions from the Colorado Dep:Utmenr of Namr.! Resources have been delered from the hydrograph whenever a separate accouming of those operations was recorded. The purpose of chese adjusrments was co creare a baseline Arkansas River hvdrograph thac reflecrs expected flows when the project is operaced '" oprimize warer available for consump- tive use and for hydroelectric generation. In the nexr chapcer. chis baseline hydrograph will be compared co che flows needed CO support namral resource values. 14