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<br />Because of the anomalous nature of these results several regression analyses were <br />performed, as well as a site inspection of the gage location. The purpose of this exercise <br />was to determine if the data at the Eagle gage was indeed anomalous, or if it needed to <br />be included as systematic data in the Log Pearson Type III analysis. <br /> <br />Several steps were performed. First, a regional comparison with the adjacent Roaring <br />Fork River drainage was utilized as a veracity check on the validity of the data. The <br />analysis was limited to pre- Ruedi reservoir, to minimize systematic error caused by <br />flood retention within the reservoir. Regression analysis with the Roaring Fork River at <br />Glenwood Springs gage revealed a good correlation between the Eagle River below <br />Gypsum gage and the Roaring Fork River at Glenwood Springs (Figure 3), with a <br />correlation coefficient of ~= 0.87. A comparison of the Eagle River at Eagle gage to the <br />Roaring Fork at Glenwood Springs gage revealed a lower correlation, with r2=0.79, <br />indicating a less reliable relationship between the gages (Figure 4). <br /> <br />Secondly, a site inspection revealed that the gage had been located at an incised <br />section of stream at a bridge crossing. While the original bridge has long since been <br />replaced, it was concluded that possible flow expansion or turbulence issues on the <br />downstream side of the bridge may have caused the rating curve to have an upward <br />shift and possibly exaggerate actual flows. Thus, based on the relatively short period of <br />record (as compared to the gage below Gypsum) and the irreconcilable results when <br />compared with other gages, the gage information was considered to be less reliable than <br />the gage information from the 57 years of record for the Eagle River below Gypsum <br />gage and thus was not used in the analysis. <br /> <br />The Eagle River at Eagle gage was the only gage on the Eagle River between Gypsum <br />and Avon. And, the gage at Avon has a short record (10 years). Thus, the reach of <br />Eagle River between Gypsum and Minturn had limited data to help predict flood flows. <br /> <br />To rectify the lack of data between Minturn and Gypsum, CWCB, Eagle County and <br />Water Resource Consultants, LLC subsequently agreed to perform an areal analysis <br /> <br />11 <br /> <br />~ <br /> <br />Water Resource Consu I tants, LLC <br />.....l <br />