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maintain at least a 1-foot water depth in the entire reach. An instantaneous <br />flow should be maintained rather than a mean daily flow of 300 cfs to eliminate <br />possible daily fluctuations when flows may fall far below the recommended <br />minimum. During low-flow periods, a uniform, constant flow of 300 cfs should be <br />implemented. The 300 cfs minimum flow is especially important to maintain during <br />the summer low-flow period so that endangered fish will have access to the fish <br />passageway. This is based on the assumption that sub-adult and adult Colorado <br />squawfish need at least a water depth of 1 foot to move both up- and downstream <br />through areas within the reach that have critically shallow water depths. <br />RECOMMENDATI'ONS' <br />Recommendations for the 2.3-mile reach of the Lower Gunnison River include: <br />1) provide a year-round, instantaneous 300 cfs minimum flow that will mimic a <br />naturally-shaped hydrograph during low flows, 2) continue to obtain biological <br />and hydrological data to evaluate the 300 cfs minimum flow for passage of sub- <br />adult and adult Colorado squawfish that includes measuring water depths at <br />critically shallow areas, correlating with known flows, and observing the <br />response of both endangered and native fishes, and 3) collect habitat-use data <br />from Colorado squawfish currently radiotagged at various low flows to refine or <br />validate the minimum flow recommended for passage. <br />xvii