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<br />HYDROLOGY <br /> <br />As stated previously, flood projections were high for 1996. A peak of 775 <br />m3 j s (27,370 f3 j s) was expected at Jenson. The flood peak however, did not <br />reach the level predicted, and was approximately 625 m3 j s (22,100 f3 j s) at Ouray <br />and 680 m3 j s (24,000 f3 j s) at Mineral Bottom. This was most likely the result of <br />a post peak refreeze which increased the duration of the snowmelt and lowered <br />the peak. Evidence of this is shown in the 1996 annual hydro graphs by the three <br />peaks on the descending limb and the longer duration of the descending limb <br />(Fig. 5 and 6). For comparison, the flood peaks at Ouray for 1984,1993 and 1994 <br />were 1,140 m3js (40,250 f3js), 570 m3js (20,129 f3js) and 331 m3js (11,689 f3js), <br />respectively. From this perspective, the 1996 flood was large for the recent past <br />but was only about one-half the magnitude of the largest post dam peaks. <br />Allred and Schmidt (1996) provide a detailed summary of Green River flood <br />peaks. <br /> <br />METHODS <br /> <br />Data Collection <br />Cross Sections <br />The data collection dates and the corresponding discharges are shown on <br />FIGURES 4 and 5, for Ouray and Mineral Bottom, respectively. The following <br />procedure was used to survey cross sections: <br />1. A tag line marked in 10-It. increments is strung across the river between the <br />bench marks. <br />2. An electronic total station is used to survey all the breaks in slope of the bank <br />from the bench mark down into the water. <br />3. Using a paper-trace depth-sounder, the depth of the river at 10-It. increments <br />is recorded. <br />· Four passes are made for each cross section <br /> <br />9 <br />