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The Draft Flow Recommendation Report also includes a minimum flow for the lower 3 miles of the Gunnison River below the Redlands Diversion for 300 cfs during some parts of the year. Specific releases may be necessary at times to maintain this minimum and are determined on a day to day basis. Because it takes approximately one day for this specific release to reach the lower end of the Gunnison River, flow may occasionally drop be 300 cfs. Based on forecasted inflows; forecasted demands (Gunnison Tunnel and other downstream requirements, which include the flow recommendation demand hydrograph); and storage or release of storage; a volume of water that should be released before the end of the forecast period is determined. This volume is generally referred to as the operation volume. Operation volume is converted to a daily cfs rate and added to the required downstream releases to compute the desired total release. Actual releases equal this desired release unless policy or physical constraints are triggered. Required downstream releases include tunnel diversions and canyon requirements. Canyon requirements include a minimum flow of 300 cfs, the flow demand hydro graph, and the minimum flow needed that least impacts the spawning and incubation of brown and rainbow trout. Constraints which may be applied to the computed release include 1) ramping rates for safety and fisheries in the Black Canyon, 2) flood control decisions both at Blue Mesa and Delta, and 3) powerplant limitations. At Blue Mesa, the daily release is set to be "Canyon Requirement + Gunnison Tunnel Demand - Side' Inflow to Crystal and Morrow Point + Crystal Operation Release." Blue Mesa daily releases may be reset by following constraints: 1. If the desired Blue Mesa release results in Blue Mesa exceeding its maximum content, release are increased. 2. Blue Mesa releases are reduced if flows at Delta exceeded 14,000 cfs on the previous day. 3. Blue Mesa releases are adjusted if ramping rates (either up or down) in the canyon are exceeded. 4. Blue Mesa releases are increased if the minimum brown or rainbow trout spawning or incubation flow, or the minimum canyon flow of 300 cfs are not met (Can occur due to tunnel diversion changes). 5. During Jan-Mar, releases are limited so that all releases at Crystal go through the powerplant. 6. Blue Mesa release will be increased, subject to downstream ramping criteria, if short term forecasting projects a spill at Blue Mesa. The release is the minimum of 6,000 cfs or the release which would result in having 2 feet of storage space remaining at the end of the short term forecast. If Blue Mesa fills, releases are set equal to the inflows. 7. Blue Mesa will not make a release specifically for the flow recommendation demand hydro graph if it causes Morrow Point releases to exceed the ma'{imum set for the specific run. 8. Blue Mesa release will be increased in blocks of 50 cfs if flow below the Redlands Diversion Dam falls below the minimum recommended for the lower reach of the Gunnison River. These releases are not available to the Redlands Diversion Dam. 9. Ifhigh fall releases are anticipated, June and July flows may be increased. This provides for additional power generation and more stable canyon flows. A -2-