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<br />Agenda Item] 7f
<br />May 22-23,2000 Board Meeting
<br />Page 2 of3
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<br />recommendations for the Gunnison River and Colorado River downstream of the
<br />Gunnison confluence. These flow recommendations will be measured at the USGS
<br />Gunnison River gage near Whitewater, Colorado and the USGS Colorado River gage
<br />near Cisco, Utah.
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<br />Gunnison River Flow Recommendation near Grand Junction, Colorado
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<br />Hydrologic Category Peak flow, cfs Base Flows, cfs
<br />Dry ~ 4,000 ~ 1,050, Jun - Aug; ~ 750, Sep - Feb
<br />Moderately Dry ;:>: 7,000 ;:>: 1,050, Jun - Oct; ;:>: 750, Nov - Feb
<br />Average Dry ;:>: 9,500 1,050 - 2,000, Jul-Feb
<br />Average Wet ;:>: 12,500 1,050 - 2,000, Jul-Feb
<br />Moderately Wet ~17,000 1,500 - 2,500, Jul-Feb
<br />Wet ;:>: 22,500 1,500 - 2,500, Jul-Feb
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<br />Colorado River Flow Recommendation near Cisco, Utah
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<br />Hydrologic Category Peak flow, cfs Base Flows, cfs
<br />Dry ;:>: 12,000 ;:>: 2,000, Jul- Aug
<br />Moderately Dry ;:>: 20,000 3,000 - 4,000, Jul - Feb
<br />Average Dry ;:>: 27,000 3,000 - 4,000, Jul - Feb
<br />Average Wet ;:>: 35,000 3,500 - 4,500, Jul - Feb
<br />Moderately Wet ;:>:43,000 3,500 - 4,500, Jul - Feb
<br />Wet ;:>: 55,000 ~ 5,000 Aug - Feb
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<br />The duration of the peak flows is for 2-3 days and ramping rates out of Crystal Reservoir
<br />vary between 300 to 500 cfs per day depending on volume.
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<br />Discussion
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<br />On May 2, 2000 a memorandum was sent to the FWS with the comments of the CWCB
<br />on the draft final report. It is our understanding that the CWCB comments will be
<br />incorporated where the FWS feels it is appropriate as well in a comment section. This
<br />draft final report has just completed peer reviewed and is being revised. It is anticipated
<br />that the final report will be completed in time for discussion by the Biology Committee at
<br />their June meeting.
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<br />Based on our initial review, we are generally pleased that the flow recommendations are
<br />tied to the climatic and hydrologic conditions that exist in the basin during any given year
<br />rather than having a frequency specifically attached to them. However, we are concerned
<br />that forcing uncontrolled spills during wet years is not good reservoir management and
<br />could cause downstream flooding problems. Therefore, we have asked that the wet year
<br />flow recommendations be eliminated and that flows simply be allowed to be whatever
<br />happens to occur in those years.
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