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<br />acre feet as the amount of water available from Blue Mesa for the interim water agreement, it <br />was decided that a 300 cfs flow recommeruJation for July through October would represent up <br />to 73,190 acre feet, which would be well underthe 148,000 acre foot number. Thus the 148,000 <br />figure does not play a siglljficanr pan in developing the interim lmIer agreement. <br /> <br />As junher background, the interim agreement does provide for the release of sufficient water to <br />maintain a minimum flow of 300 eft during July through October below the Redlands Diversion <br />Dam. Under worst case conditions, this would require an Aspinall release of 73,190 acre feet. <br />Additional releases would be required to meet operational commitments as outlined in the interim <br />agreement to satisfy downstream Gunnison River mainstem users senior in priority to the Aspinall <br />Unit decrees year-round as hydrologic conditions and available lmIer supplies allow. <br /> <br />For purposes of studies associated with this repon, such hydrologic conditions were assumed to <br />be met if the flow at the Gunnison River near lWIitewater was kept at 1,095 cfs. Operation <br />studies covering the period November 1973 through September 1994 were prepared for <br />evaluation of No Action and Alternatives A and B. These shaw no net difference in total Aspinall <br />Unit releases. Operation studies sJwwed that commirmenrs in the interim agreement can be met <br />under all but very dry year conditions (such as occurred in 1977) by redistribution of historic <br />release pallems. <br /> <br />In the operation studies, Aspinall Unit releases were reduced below thase required to meet <br />desired flow levels if hydrologic conditions indicated that the projected volume of Blue Mesa <br />Reservoir would drop below 400,000 acre feet by the end of the calendar year. Under such <br />conditions, operations were modified and sJwnages to senior water rights and fish flows were <br />shared. <br /> <br />The operation study completed for Al1emarives A and B sJwwed thatlmler year 1977 was the <br />only year in which the end of the year content of Blue Mesa Reservoir was expected to drop <br />below the 400,000 acre-foot target. For example purposes, the operation study shaws a passible <br />shonage scenario for 1977 in which flows below the Redlands Diversion Dam were allowed to <br />go to zero in March through June and only 200 eft was provided below Redlands during July <br />through October. This is an example of Jww, under cenain dry year conditions, supplies to <br />water rights could be impacted: Aspinall releases are cunailed while a ponion of flows <br />available to downstream senior users under No Action conditions are reallocated to fish flows <br />below Redlands Diversion Dam. <br /> <br />Summary statistics sJww an average annual increase in flows below Redlands of 1 ,416 acre feet <br />offset by an average annual decrease inflows available to wOrer rights below lWIitewater by an <br />equal amount. This represents a reallocation of available flows at the lWIitewater gage between <br />water right users and fish flows below Redlands. <br /> <br />Additional infonna1ion has been added to the final EA. on the effect of the propasals on Blue <br />Mesa Reservoir. In addition, tables have been added to Appendix E shawing effects on reservoir <br />elevation. <br /> <br />51 <br />