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<br />Recommended Magnitudes and Duration of Maximum Spring Peak and Summer-to-Winter Base Flows
<br />for Endangered Fishes in the Green River Downstream from Flaming Gorge Dam
<br />
<br /> HYDROLOGIC CONDITIONS AND FLOW RECOMMENDATIONS'
<br /> MODER~EL Y AVERAGED MODER~ELY ORyF
<br /> WET" WET DR
<br /> (10-30% (30 - 70% (70-90% (90 - 100%
<br />GREEN RIVER REACH FLOW PERIOD (0-10% exceedance) exceedance) exceedance) exceedance) exceedanee)
<br />Reach' Maximum Spring ~8,800 cf. 24,600 cf. :t4,600 cf. 2;4,600 cIs 2;4,600 ets
<br />Flaming Gorge Dam P..k Flow (244 m3/s) (130m'/s) (130m'/s) (130 m'/s) (130m'/s)
<br />to
<br />Vamps River Peak flow duration is dependent upon the amount of unregulated inflows into the Green River and the flows needed to achieve the
<br /> recommended flows in Reaches 2 and 3.
<br /> Summer.to-W1nter ',800-2,700 cf. 1,500-2,600 cf. 800-2,200 cf. 800-',300 cf. 800-' ,000 cl.
<br /> Ba.. Flow (50-eO m3/s) (42-72 m3/s) (23-62 m3/s) (23-37 m3/s) (23-28 m3/s)
<br />R.ach 2 Maximum Spring :1;26,400 cf. 2;20,300 cf. 2;18,600 cfaG :tB,300 cf. 2;8,300 cf.
<br />Vampa River Peak Flow (748 mala) (575 ma/s) (527 ma/s) (235 mala) (235 mals)
<br />to ~8,300 cfsH
<br />White River
<br /> (235 ma/s)
<br /> Peak Flow Flows greater than Flows greater than Flows greater than Flows greater than Flows greater than
<br /> DuratIon 22,700 cfs (643 ma/s) 18,600 ets (527 ma/s) 18,600 cfs (527 8,300 cfs (235 ma/s) 8,300 ets (235 ma/s)
<br /> should be maintained should be maintained ma/s) should be should be should be maintained
<br /> for 2 weeks or more, for 2 weeks or more. maintained for at maintained for at for 2 days or more
<br /> and flows;>: 1 8,600 least 2 weeks in at least 1 week. except in extremely dry
<br /> (527 mals) for 4 weeks least 1 of 4 average years (;>:98%
<br /> or more. years. exceedance).
<br /> Summer~to-W1nter 2,80Q.3,OOO cf. 2,400-2,800 cf. 1,500-2,400 cf. 1,100-1,500 cf. 900-1,100 cf.
<br /> B..e Flow (79-85 ma/s) (69-79 m3/s) (43-67 ma/s) (31-43 ma/s) (26-31 m3/s)
<br />Reach 3 Maximum Spring ~39,OOO cf. ~24,OOO cfs 222,000 cf.1 28,300 cf. 28,300 cf.
<br />WhHe River Peak Flow (l,l04ma/s) (680 m3/s) (623 m3/s) (235 ma/s) (235 m3/s)
<br />to
<br />Colorado River
<br /> Pe.k Flow Flows greater than Flows greater than Flows greater than Flows greater than Flows greater than
<br /> Duration 24,000 cfs (680 m3/s) 22,000 cfs (623 mals) 22,000 cfs (623 8,300 ets (235 ma/s) 8,300 cfs (235 m3/s)
<br /> should be maintained should be maintained m3/s) should be should be should be maintained
<br /> for 2 weeks or more, for 2 weeks or more. maintained for maintained for at for 2 days or more
<br /> and flows greater than 2 weeks or more in least 1 week. except in extremely dry
<br /> 22,000 cfs (623 ma/s) at least 1 of 4 years (<:98%
<br /> for 4 weeks or more. average years. exceedance).
<br /> Summer-to-Winter 3,200.4,700 cf. 2,700.4,700 eta 1,800.4,200 cf. 1,500-3,400 cf. 1,300-2,600 ef.
<br /> Ba.8 Flow (92-133 m3/s) (76-133 mIls) (52-119 mals) (42-95 m3/s) (32-72 ma/s)
<br />
<br />A _ Recommended flows as measured at the United States Geological Survey gauge located near Greendale, Utah, for Reach 1; Jensen, Utah,
<br />for Reach 2; and Green RiVer, Utah, for Reach 3.
<br />B _ Wet (0 _ 10% exceedance): A year in which the forecasted runoff volume is larger than almost all of the historic runoff volumes. This hydrologic
<br />condition has a 10% probability of occurrence.
<br />
<br />C _ Moderately Wet (10 _ 30% exceedance): A year in which the forecasted runoff volume is larger than most of the historic runoff volumes. This
<br />hydrologic condition has 8 200k probability of occurrence.
<br />0- Average (30.70% exceedance): A year in which the forecasted runoff volume is larger than about one-half of the historic runoff volumes.
<br />This hydrologic condition has 8 40% probability of occurrence.
<br />E _ Moderately Dry (70.90% exceedance): A year in which the forecasted runoff volume is less than most of the historic runoff volume. This
<br />hydrologic condition has a 20% probability of occurrence.
<br />
<br />F _ Dry (90 _ 100% exceedance): A year in which the forecasted runoff volume is less than almost all of the historic runoff volumes. This
<br />hydrologic condition has a 10% probability of occurrence.
<br />
<br />G. Recommended flows 218,600 cfs (527 mals) in 1 of 2 average years.
<br />H . Recommended flows <: 8,300 cfs (235 m3/s) in other average years.
<br />I _ Recommended flows ~ 22,000 cfs (623 ma/s) in 1 of 2 average years.
<br />
<br />M'/s = cubic meters per second
<br />
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