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<br />capacity. The maximum average daily release of 933 cfs was made on <br />July 13, 1995, and the maximum storage of 103,927 acre-feet occurred <br />on July 14, 1995. Releases were then reduced until they were below the <br />recommended maximum fishery flow (250 cfs) by the middle of August. <br /> <br />The total April through September inflow was 154,235 acre-feet, which <br />was 130 percent of average and greater than the reasonable maximum <br />forecast inflow. The high inflows were due, in part, to waters left in the <br />Fryingpan River Basin which normally would have been diverted to the <br />East Slope but were not because the reservoirs on the East Slope had <br />fllled during the spring runoff. <br /> <br />No call was placed on the Colorado River at the Cameo gage by senior <br />water right holders due to high flows in the Colorado River throughout <br />the irrigation season. Because of that, there were no releases made for <br />either Project depletions or for depletions caused by Ruedi Reservoir <br />water contract holders during the 1995 water year. High flows in the <br />Colorado River also eliminated the need to release any water to augment <br />the habitat of endangered aquatic species in the Colorado River <br />downstream of the Grand Valley Diversion Dam and above the <br />confluence with the Gunnison River. <br /> <br />The Corps of Engineers estimated that the operation of Ruedi Reservoir <br />to fill the operating storage, the Boustead Tunnel diversion, and <br />Turquoise Lake prevented $1,770,000 of flood damage in the Colorado <br />River Basin during 1995. <br /> <br />Homestake Reservoir Dam was constructed on Homestake Creek in 1967 for water diversion to <br />Colorado Springs and Aurora. It has acted to inadvertently reduce the peak flood discharges on <br />the lower Eagle River. The dam was not constructed for flood control, but acts to fill during the <br />spring runoff and has reduced peak flooding on the Eagle River. <br /> <br />An informal levee exists along the north bank of the Eagle River at the gravel ponds in Dotsero. <br />This levee was field investigated and determined to be "non-FEMA compliant," meaning it does <br />not have a formal maintenance program, may not withstand I OO-year flooding, and does not have <br />the required freeboard. Further, the field investigation indicated that once the floodwater does <br />breach the levee, it would be effective flow. <br /> <br />No other significant flood control resources affect the flooding sources in Eagle County. <br /> <br />3.0 ENGINEERING METHODS <br /> <br />For the flooding sources studied by detailed methods in the community, standard hydrologic and <br />hydraulic study methods were used to determine the flood-hazard data required for this study. Flood <br />events of a magnitude that is expected to be equaled or exceeded once on the average during any 10-, 50-, <br />100-, or 500-year period (recurrence interval) have been selected as having special significance for <br />floodplain management and for flood insurance rates. These events, commonly termed the 10-, 50-, 100-, <br />and 500-year floods, have a 10-,2-,1-, and 0.2-percent chance, respectively, of being equaled or exceeded <br />during any year. Although the recurrence interval represents the long-term, average period between <br />floods of a specific magnitude, rare floods could occur at short intervals or even within the same year. <br />The risk of experiencing a rare flood increases when periods greater than 1 year are considered. For <br />example, the risk of having a flood that equals or exceeds the 100-year flood (I-percent chance of annual <br />exceedence) in any 50-year period is approximately 40 percent (4 in 10); for any 90-year period, the risk <br />increases to approximately 60 percent (6 in 10). The analyses reported herein reflect flooding potentials <br /> <br />16 <br />