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<br />Technical Work Group (TWG), and the Grand Canyon Monitoring and Research Center <br />(GCMRC). <br /> <br />Planning efforts in 1998 by GCMRC, the Upper Colorado Region Bureau of Reclamation, the <br />TWG, and the GCMRC Information (Planning) Group suggest that the following procedures will <br />improve coordinatioo between the Adaptive Management Program, the Colorado River <br />Management Workgroup (CRWG), and the Bureau of Reclamation in advising the Secretary on <br />preparation of the annual operating plan (AOP) for GCD <br /> <br />I, GCMRC provides to AMWGrrWG and the CRWG the annual State of the Colorado <br />River Ecosystem Report, <br /> <br />2. In response to hydrologic scenarios prepared by the Bureau of Reclamation, GCMRC <br />proposes adaptive contingency flow alternatives for discussion with the TWG and <br />AMWG. <br /> <br />3, AMWG proposes to the CRWG the Adaptive Contingency Flows Plan to protect and/or <br />enhance the Colorado River ecosystem and associated Tesources in the upcoming Water <br />Year, characterizing expected resource changes. <br /> <br />4, The CRWG and AMWG discuss and make recommendations to the Secretary on the flow <br />regimes for the upcoming Water Year, continue to discuss Glen Canyon Darn operations <br />throughout the year, and recommend adjustments in releases as hydrologic conditions <br />change. <br /> <br />Potential Water Year 1999 Flow Scenarios; October 1, 1998.September 30,1999 <br /> <br />Following are descriptions of potential 1999 Water Year scenarios and the pTOS and cons of <br />various flow regimes. A schedule of releases is discussed for the most likely flow regimes. This <br />information is useful to understand proposed flow regimes in the following section. <br /> <br />Runoff Scenario 1: This scenario involves a full or nearly full reservoir condition (which <br />currently exists) but low or normal expected inflows to Lake Powell in Water Year 1999. <br />Therefore, the capability of averting flood-like conditions is good and the risk of a spill is low. <br />Lake Powell would reach:$ full pool stage by 1 July 1999 and the annual release volume would <br />be:$ 8.23 Maf. <br /> <br />Under low/normal inflow conditions, releases from Lake Powell would not be likely to exceed <br />25,000 cfs. Under the ROD, these releases could have daily fluctuations of 8,000 cfs, but as the <br />average daily flows approach 25,000 cfs they would most likely be made as steady flows. Such <br />flows are consistent with the ROD and preliminary reports on the high steady releases of Water <br />Years 1997 and 1998 suggest that these flows benefit the aquatic food base and potentially the <br /> <br />[WORKING DRAFT 2 - GCMRC: 12/04/98] 4 <br />