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I I I I I I I I I I I I I I I I I I I 5 in streamflow forecasts made a year in advance is limited, the data are valuable in analyzing the possible impacts on project uses and purposes. Based on the ESP model results, three different hydrologic scenarios were developed and are shown in Table 2. With the exception of the San Juan River Basin, dry basin conditions resulted in the magnitude of inflows in the three scenarios that are less than the historical upper decile, mean and lower decile. Reclamation's monthly reservoir computer model is used to plan reservoir operations for the upcoming l2-month period. The inflow volumes resulting from the above assumptions and current reservoir storage conditions were used as model input and monthly releases were adjusted until release and storage levels accomplished project purposes and priorities. 1993 RESERVOIR OPERATIONS At several locations in both the Upper and Lower Basins, minimum instream flow levels have been established which preserve the present aquatic resources downstream of certain Colorado River Basin dams. The construction and operation of dams in the basin have had both positive and negative effects on aquatic resources. Controlled cool water releases from dams in the Colorado River Basin have provided for increased productivity of some aquatic resources and the development of significant sport fisheries. However, the same releases could be detrimental to endangered and other native species of fishes. Section 7 consultations were continued in 1992 on the operation of the Aspinall Unit on the Gunnison River and the Animas LaPlata Project on the San Juan River (which affects the operation of Navajo Reservoir). These, along with the ongoing Section 7 consultation on Flaming Gorge and the interim flow restriction on releases from Lake Powell, will continue in water year 1993. Studies associated with these consultations will be used to better understand the flow- related needs of the endangered and other native species of fish. Modifications to planned operations may be made based upon changes in forecasted conditions. However, because of the Recovery Implementation Program for Endangered Fish Species in the Upper Colorado River Basin, Section 7 consultations, and other downstream concerns, modification to the monthly operation plans are no longer primarily forecast based. Decisions on spring peak releases and downstream habitat target flows must be made midway through the runoff season. Reclamation and the Fish and Wildlife Service (FWS) will initiate meetings with interested parties, including representation of the basin states, to facilitate the decisions necessary to finalize site specific operations plans. All operations will be undertaken subject to the primary water storage and delivery requirements established by the Law of the River.