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<br />A-2 <br />gradually grown to include a wide range of interests. The AOP process is now much <br />more a public process with decisions appropriately discussed and debated. Risks and <br />benefits are clearly stated and greater analysis accompanies the proposed plan. While <br />the final decisions still lie with the Secretary of the Interior, this process has produced <br />greater involvement, a broader range of ideas, and better decision making. Discussions <br />in the group satisfy the consultation provisions of the 1968 Act and the 1992 Grand <br />Canyon Protection Act regarding the AOP prepared under the 1968 Act. <br /> <br />The work group discusses many key issues regarding monthly and annual operation of <br />Glen Canyon Dam. In recent years these issues included surplus/normal determinations, <br />spill avoidance procedures, meeting firm power commitments, and research flows <br />(including the spike flow), Since the AOP covers one water year (October 1 through <br />September 30), Reclamation seeks comments from the group on its production of <br />computer analysis and narrative for issuance by the Secretary of the Interior on October <br />1 of each year. Several meetings are held each year, typically starting in the spring and <br />concluding in August. Several alternative hydrologic scenarios are considered for the <br />following year, illustrating the range of decisions and conditions that could be expected. <br />The resulting plans of operation include consideration of all project purposes. <br /> <br />Other key dates during each year's operation are January 1 and July 31. These <br />respectively represent the dates when the first spring runoff forecast is available and <br />when the reservoir is at its fullest point. The January 1 target affects the expected winter <br />drawdown and is a springboard for future changes in scheduled release decisions which <br />react to changing weather and forecast conditions. The July 31 target represents a <br />compromise among m~imi7ing conservation storage, avoiding spills, and dam safety <br />issues. Both of these targets are adjusted until the storage and release regime comply <br />with existing statutes and meet project needs. <br /> <br />Typical Reservoir Conditions <br /> <br />If reservoir storage is low and Lake Powell is not expected to fill, annual releases of 8.23 <br />MAF are likely. Less risk of spills and over release of water and greater flexibility in <br />determining releases usually exist when the reservoir is not expected to fill. The pattern <br />of these monthly releases usually matches that of firm power commitments with higher <br />releases during winter and summer months. Monthly release volumes vary between <br />about 0.55 MAF and 0.9 MAF. Annual releases are sometimes required to be higher <br />than 8.23 MAF to balance storage levels between Lakes Powell and Mead. The <br />magnitude and duration of these equalization releases are unknown until much of the <br />spring runoff has passed, usually late-June or July. Thus equa1ization water is usually <br />released during the summer months prior to the end of the water year. <br /> <br />If reservoir storage is high and Lake Powell is expected to fill, annual releases nearly <br />match the annual inflow. To manage water during full reservoir conditions, the highest <br />priority must be given to dam safety concerns. The risk of spilling water becomes a <br />factor, with dam safety as well as economic and environmental implications. Releases <br />