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<br />. <br /> <br />. <br /> <br />wet hydrologic conditions (Muth et al. 2000) because flows in moderately dry or dry years are <br /> <br />usually insufficient to achieve substantial river-flood plain connections. These flow <br /> <br />recommendations were implemented in 2006; therefore, their evaluation was not originally <br /> <br />identified as an objective for this project. However, because implementation of <br /> <br />recommendations overlaps with one year of this study and are consistent with the study <br /> <br />objectives, there may be some potential to evaluate efficacy of recommendations. <br /> <br />Because provision of flood plain habitat to benefit native fishes is mainly an hypothesis, <br /> <br />research and monitoring is ongoing to test that hypothesis. Flow recommendations list <br /> <br />uncertainties regarding the response of native fishes to certain flow and temperature regimes <br /> <br /> <br />(Muth et al. 2000). Specific uncertainties include whether there is a need for increased flows and <br /> <br /> <br />the suitability of release durations to link the Green River with flood plain wetlands, especially in <br /> <br /> <br />average flow years (U.S. Department ofthe Interior 2005). Recommendations in average <br /> <br />hydrologic conditions, which occur in about four of every 10 years, call for flows in Reach 2, the <br /> <br />middle Green River from downstream of the Yampa River to the head of Desolation Canyon, <br /> <br />Utah, to meet or exceed 527 m3/sec (18,600 cubic feet per second [ft3 /sec]) in one of two average <br /> <br />flow years, and that flow level should be maintained for at least two weeks in one of every four <br /> <br />years. Some resource managers have questioned recommendations that would be implemented <br /> <br />during average hydrologic conditions, mainly because lowering or removal of levees may <br /> <br />enhance riverine connections sufficiently without the need for increased Flaming Gorge Dam <br /> <br />flow identified in the recommendations (Green River Study Plan adhoc Committee 2007). No <br /> <br />recommendations were made for the upper limit of any peak flow under any hydrologic <br /> <br />condition because a greater extent of flood plain inundation was viewed as beneficial to native <br /> <br />fishes. <br /> <br />. <br /> <br />. <br /> <br />. <br /> <br />. <br /> <br />. <br /> <br />. <br /> <br />. <br /> <br />. <br /> <br />15 <br /> <br />. <br />