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<br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br /> <br />been recorded, the gage had never been calibrated for flows greater than <br />600 cfs and had a rock sill control which had moved during floods. TEA has <br />just executed a separate floodplain analysis contract for the upper end of <br />Eldorado State Park and the gage site, which may provide further background <br />on flood level readings. <br /> <br /> <br />The use of the gage data for flood statistics should probably be considered <br />more qualitative and a reasonableness check. The sponsors decided that we <br />shouldn't proceed further with gage investigation. <br /> <br />3. Flood of Mav 1969. The 1969 event was investigated. The Denver data for <br />Gross indicated that the upstream flood was trapped at the reservoir. The <br />USBR provided their files for rainfall data and analysis of the 1969 event. <br />CU provided 15 minute rainfall data for the Boulder Creek watershed. While <br />there were daily rain gage readings within the basin, there were no 5 or 15 <br />minute rain data within the watershed. Review of 1969 isopluvial maps from <br />the USBR indicated that there could be a wide range of interpretation, with a <br />resultant wide range of estimated model flows. Henz indicated that he might <br />be able to review other data and construct detailed rainfall patterns at <br />various locations in the watershed. The sponsors decided not to pursue this <br />calibration concept further due to the expense and likely questionable results. <br /> <br />4. UDDer Basin ModelinQ. Upon review of the Corp's model data for the <br />mountains, TEA decided it was better to completely review all data for <br />consistency to UDFCD/Boulder standards and correctness. Only the outline <br />of the basins and element numbers were kept. <br /> <br />CONSULTATIONS <br /> <br />Numerous consultations with government and private agencies have taken place, <br />highlighted as follows: <br /> <br />· City and County of Boulder <br /> <br />-CADD base same <br />-Rainfall criteria for frequent events <br />-Stream gage data <br /> <br />. Colorado Division of Water <br />Resources (CDWR) <br /> <br />· Colorado State Engineer's Office <br /> <br />-Gross and Marshall Lake Reservoir and <br />Spillway characteristics <br /> <br />. Colorado State University (CSU) <br /> <br />-Fort Collins rainfall <br />-Precipitation studies <br /> <br />1-7 <br />