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<br />" <br /> <br />Peak flows exceeded 30,000 cfs at the state line 23 years out of 51 in the period of record <br />used to rationalize flow recommendations for the IS-mile reach. So, the recommendation that high <br />flows occur 25% of the time is somewhat confusing. According to Doug Osmundspp (U.S. Fish <br />and Wildlife Service, Grand Junction, CO, personal communication) this really means that at least <br />one year in four should have peaks of 30,000 - 40,000 cfs, and currently, that is indeed the case. <br />However, peak flows at the state line gauge are due in large part (47%) to discharge from the <br />Gunnison River, and it is not clear how that system fits into the picture. This seems problematic if <br />different flows are ultimately derived for the Gunnison River. <br />Currently, squawfish population dynamics and spawning success are unknown in the <br />Gunnison River, even though squawfish have been collected above the Redlands diversion dam. <br />Reregulated flows and removal of the diversion dams, provision of bypass devices or introduction <br />of cultured stocks may allow the squawfish and razorback sucker to recover in the Gunnison River. <br />The same applies to the Colorado River with respect to the Palisade diversion dams that delimit the <br />upstream end of the IS-mile reach. Conditions seem very favorable for squawfish and razorback <br />sucker upstream from diversion structures on both rivers, although temperature regimes may be on <br />the cold side of optimum for growth and production. <br />Because peak flows also are needed on the Gunnison to rebuild habitat, the <br />recommendations for the IS-mile reach may be higher than needed. Similar concerns may apply to <br />other tributaries, especially the Dolores and White Rivers. However, the flow recommendations for <br />the Colorado River are more solidly rationalized and data-based than recommendations for the <br />Green River in the context of my review and synthesis of the river ecology of the Upper Colorado <br />River Basin and the interactive effects of regulation. The recommended peaks and baseflows more <br />closely reflect predam conditions, in spite of the dramatic depletions that have occurred in the <br />Colorado River above the Gunnison River confluence (Figure 8). <br /> <br />61 <br />