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<br />. - ro .., " <br />~v~.... <br /> <br />., <br /> <br />discharge of the Platte River at Overton due to Narrows Dam and <br />Reservoir is anticipated due to the distance of about 300 river miles <br />between the proposed Narrows Dam and the crane habitat area. Also, <br />'there is a contributing drainage area below the Narrows Dam site and <br />Kingsley Dam of about 15,200 square miles. Rainfall events occurring <br />over these 15,200 square miles would continue to produce large peak <br />floods resulting in no significant changes in the peak flows having a <br />recurrence interval of 2 years. <br /> <br />Ice jams will continue to occur with the resultant scouring action <br />movement and continual shifting of the streambed that helps maintain <br />the open channel of unvegetated sandbars (USBR, 1977). <br /> <br />Impacts to the Wet Meadow Complex <br /> <br />There are two "schools of thought" within the Department of the Interior <br />regarding the impacts of additional flow depletions on wet meadow <br />habitat.. It is stated on pages 9 and 87 of the Geological Survey <br />report (1975): <br /> <br />"The survival of the wet-meadow compl ex adjacent to the Platte <br />River in central Nebraska probably is dependent on relatively <br />high river stages during the winter and early spring. The <br />probable hydrologic factors that affect the ecologic health <br />of the wet-meadow complex include high stream stages that <br />result in a high water table during the January-April period. <br />The hi9h water levels during this period provide for healthy <br />growth of the wet-meadow vegetation that discourages the <br />encroachment of other vegetation." <br /> <br />The Fish and Wildlife Service believes that cumulative surface flow <br />depletions from planned and proposed water resource development <br />projects and varied types of land development, as described previously, <br />could eventually lead to the ,loss of most of the Platte's wet meadow <br />habitat. <br /> <br />According to the Bureau of Reclamation's Narrows Unit Final Environmental <br />Statement (1976): <br /> <br />"The Narrows Unit will have little effect on the late winter <br />and early spring flows of the Platte River on the average. <br />The peak flows on the South Platte River are somewhat later,. <br />i.e., May and June, and would not contribute to the vital <br />high water table during the January-April period. Therefore, <br />the wet-meadow complex should be maintained." <br /> <br />33 <br />