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e 000323 e during certain periods in order to meet the overall objectives. For example, it will not be possible with a monthly time step model to determine the contribution to increased spring peak flows that can be expected from implementing a specific alternative for providing more water to the fish. In order to determine the contribution to the spring peak, a daily time step will probably be necessary. Furthermore, in order to determine whether an alternative will violate a channel flow capacity constraint (e.g. the 1100 cfs on the Fryingpan below Ruedi) it will be necessary to have flow data on a daily basis. In both these examples, we would only need daily flow data for a relatively short period (a few weeks, perhaps one month) and not for an entire year. The Service (February 2, 1999 memo from Henry Maddux to Randy Seaholm) indicates there may be the need for some daily modeling in May and June. We will first have to determine if the additional cost and brain damage associated with a daily time step model is worth the effort and, if the answer to this question is yes, how do we go about achieving a successful and efficient daily time step model. COMMENTS: · Ray Bennett is doing a daily time step model based on StateMod. This needs to be checked out to determine if it will meet our needs. · We also need to talk to Denver Water about P ACSIM and determine if this is another option for a daily time step (especially the May 15- July 15 period) · We will need a daily time step to do the analysis of taking the call of Shoshone. 4. Are the Alternatives Included In The Preliminary Biological Opinion Out of Bounds? . The following alternatives were included in the Preliminary Biological Opinion: · Grand Valley Water Management components which include a reduction in irrigation demand under the Grand Valley Project and an operational bypass of9,000 acre-feet/year at the GVP headgate. · GVP power demand with a junior priority during summer months. (This is interpreted to mean that the GVP would not call during the summer months.) · Orchard Mesa Check operated to only benefit the Grand Valley systems (This is interpreted to mean that the Orchard Mesa Check would be operated to reduce the amount of Green Mountain Water required to make replacement and the check would not be operated to benefit upstream demands.) · HUP surplus deliveries to the 15-milereach. (This is interpreted to mean a surplus account would be established in Green Mountain Reservoir, and ifit was determined that there would be surplus water not needed to maintain historic users in priority, this water could be booked over to the surplus account where it could be used for the fish.) · Wolford Mountain Reservoir releases from the 6000 acft fish pool to the 15-mile reach · Ruedi Reservoir releases from storage accounts of 26,850 acft (available every year) and