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'. 2 The width of the Special Flood Hazard Area (SFHA) generally decreased from approximately 2,800 feet downstream of Buckley Road to East Colfax Avenue as a result of the channel modifications, with a maximum decrease in the SFHA width of approximately 2,700 feet occurring approximately 1,350 feet upstream of Buckley Road. The use of more detailed topographic mapping downstream of the channel modifications resulted in an increase in the width of the SFHA of approximately 50 feet, approximately 2,600 feet downstream of Buckley Road. All property owners affected by the increase in the SFHA have been notified. The area south of the Sand Creek channel and east of Buckly Road, previously shown on the FIRM as an SFHA designated as Zone AH (indicating base flood depths of 1 to 3 feet), has been designated as Zone X and is shaded to indicate average base flood depths of less than I foot. The channel modifications resulted in increases and decreases in the width of the floodway along Sand Creek. The maximum decrease in the floodway width of approximately 150 feet occurs at Buckley Road, and the maximum increase in the floodway width of approximately 100 feet occurs approximately 500 feet upstream of Buckley Road. All increases in the floodway width are contained within the drainage easement for Sand Creek. In our processing of this LOMR, we discovered an inconsistency between the information shown on the effective FIRM and that presented on the Flood Profiles for Sand Creek in the effective FIS report. The BFE shown on the FIRM just downstream of cross section J (approximately 1,600 feet upstream of Chambers Road) did not agree with the elevation shown on the Flood Profiles. The FIRM has been revised in the vicinity of cross section J to reflect the BFEs indicated by the Flood Profiles. The modifications are shown on the enclosed annotated copies of FIRM Panels 0045 E and 0185 E, Profile Panels 14P and 15P, and the Floodway Data Table for Sand Creek. This LOMR hereby revises these panels of the effective FIRM dated August 16, 1995, and the Flood Profiles and Floodway Data Table in the FIS report, also dated August 16, 1995. The Flood Profiles reflect a change in the channel stationing indicated by the hydraulic analysis of the revised reach. The following table is a partial listing of existing and modified BFEs: Location Existing BFE (feet)* Modified BFE (feet)' Approximately 1,600 feet upstream of Chambers Road . Approximately 200 feet upstream of Buckley Road Approximately 150 feet downstream of East Colfax Avenue Approximately 3,400 feet upstream of East Colfax Avenue 5,380 5,400 5,421 5,437 5,380 5.398 5,425 5,437 *Referenced to the National Geodetic Vertical Datum, rounded to the nearest whole foot Public notification of the revised BFEs will be given in The Aurora Sentinel on or about October 25 and November 1, 1995. A copy of this notification is enclosed. Any request for reconsideration must be based on scientific or technical data. In addition, a notice of changes will be published in the Federal Re~ister. Because this LOMR will not be printed and distributed to primary users, such as local insurance agents and mortgage lenders, your community will serve as a repository for these new data. We encourage you to disseminate the information reflected by this LOMR throughout the community, so that interested persons,