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The UDFCD published a report on Big Dry Creek (Reference 20) in March 1973. The 100-year flood profile in this report was in such close agreement that it was decided to use the UDFCD's profile except for the area around Interstate 25, which was adjusted upon approval of UDFCD to reflect our analysis. An FPI report was published in January 1966 by the USACE, Omaha District, regarding flooding along Clear Creek (Reference 12). Comparison of reports reflected discrepancies throughout the entire stream length because the present study was based on considerably higher discharges. Other discrepancies may be attributed to recent improvements, such as the Broadway crossing and the Interstate 270 interchange, which were not present in the USACE report. Upon contact, the USACE stated that their report was no longer valid. Peak discharges for Clear Creek were recomputed by the UDFCD and the revised floodplain boundaries are shown as an approximate Special Flood Hazard Area. The UDFCD published a report on Niver Creek in February 1974 (Reference 54). The report contained two 100-year profiles, one reflected existing conditions and a fully developed basin, and the second reflected channel improvements with discharges based on a fully developed basin. Since the publication, some of the channel improvements have been made. Also, the present report reflects only present basin development. Therefore, no comparison can be made between profiles. A report on Northfield Creek, prepared by Hogan & Olhausen for the City of Thornton (Reference 55), was published in March 1976. When compared, the 100-year discharges in this study were found to be different from those determined for the present study. This difference is due to the different methods used to determine the discharges. A meeting was held on April 16, 1976, with the UDFCD, the City of Thornton, Hogan & Olhausen, and Gingery Associates in order to resolve the difference in discharges. The main reason for the discrepancy was because Hogan & Olhausen considered residential areas as being 25 percent impervious while the present study used a 50 percent impervious figure, the figure recommended by the UDFCD in their USDCM for use in the Denver metropolitan area. At this meeting, a resolution was never confirmed; therefore, the FIA was contacted for a final ruling. The FIA decided to use the 50 percent impervious figure. During the appeals process, approximate flood from studies on First Creek (Reference 56), (Reference 57), and Grange Hall Creek (Reference boundaries were adopted Second and Third Creek 58). 8.0 LOCATION OF DATA Information concerning the pertinent data used in the preparation of this study can be obtained by contacting the Mitigation Division, Federal Emergency Management Agency, Denver Federal Center, Building 710, Box 25267, Denver, Colorado 80225-0267. 69