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August and from November through April. Fish flows would be reduced before water user <br />supplies were reduced from November through June under Alternative C (Table 2). Under <br />Alternatives A and B, Aspinall Unit releases would be provided to meet the needs of both fish <br />and water users on a year round basis. <br />River flow changes below Redlands Diversion Dam as a result of the alternatives are shown in <br />Table 2. The alternatives are aimed at ensuring that flows of at least 300 cfs are available to <br />the fish. There is no change in flows below Redlands Diversion Dam during wet and normal <br />years. However, differences occur during the dry (1990) and very dry years (1977). In the dry <br />year, Alternatives A and B succeed in providing at least 300 cfs year-round. This is not the case <br />for Alternative C, when average monthly flows are allowed to drop to zero in the winter months. <br />In the extreme drought year conditions, water supply shortages would be shared by both fish and <br />water users under Alternatives A and B, as represented by the 200 cfs flow shown in July <br />through September of 1977. In this example, supplies to fish were reduced by 100 cfs and <br />supplies to water users were reduced by 200 cfs. <br />Effects of the alternatives on flows through the Black Canyon of the Gunnison National <br />Monument and Gunnison Gorge are also a concern. Table 3 compares the average monthly <br />flows as measured below the Gunnison Tunnel, which is near the upstream boundary of the <br />Monument. The data reflects how the Aspinall Unit is currently operated to provide a flow of <br />at least a 300 cfs below the Gunnison Tunnel diversion. In wet, normal, and very dry years, <br />flows are nearly the same for all alternatives. Changes occur only under the 1990 dry year <br />conditions. In this example, flows increase during the winter months and in August under <br />Alternatives A and B compared to No Action and Alternative C. The increases are caused by <br />extra releases to meet the downstream needs for water users and/or endangered fish on a <br />year-round basis. <br />As indicated previously, there are several water projects being considered for development in <br />the Gunnison Basin. The water rights for these projects would not be affected by the proposals. <br />Concerns were expressed in public meetings that the fish passageway or interim water agreement <br />could lead to establishment of a more stable population of endangered fish species in the <br />Gunnison River, and this would make construction of the Dominguez Project more difficult. <br />The goal of the proposed actions is to establish a larger self-sustaining population of the <br />endangered fish in the Gunnison River. The proposed location of the Dominguez Project is in <br />a reach already designated as critical habitat for the endangered fish and already occupied by the <br />fish. Thus, protection for the fish exists on the river and will exist whether or not the fish <br />passageway and interim agreement are completed. Recovery of the fish and their removal from <br />the endangered species list is an advantage to future water development. <br />Reservoir Storage Levels - Since the interim agreement alternatives would draw from storage <br />in Blue Mesa reserved for endangered fish, there is a concern that their implementation would <br />cause reservoir storage content and associated water surface levels to drop. Table 4 compares <br />end-of-month content data for Blue Mesa Reservoir for the representative water years. It shows <br />that content does not change for all alternatives during wet and normal years, therefore the <br />22