FLOOD05107 - Laserfiche WebLink

Home Browse Search

~. CHANGES ARE MADE IN DETERMINATIONS OF BASE FLOOD ELEVATIONS FOR BOULDER COUNTY, COLORADO AND INCORPORATED AREAS, UNDER THE NATIONAL FLOOD INSURANCE PROGRAM On June 2, 1995, the Federal Emergency Management Agency (FEMA) identified Special Flood Hazard Areas (SFHAs) in Boulder County, Colorado and Incorporated Areas through issuance of a Flood Insurance Rate Map (FIRM). The Mitigation Directorate has determined that modification of the elevations of the flood having a I -percent chance of being equaled or exceeded in any given year (base flood) for certain locations in the City of Boulder is appropriate. The modified base flood elevations (BFEs) revise the FEMA FIRM for the community. The changes are being made pursuant to Section 206 of the Flood Disaster Protection Act of 1973 (Public Law 93-234) and are in accordance with the National Flood Insurance Act of 1968, as amended (Title XIII of the Housing and Urban Development Act of 1968, Public Law 90-448), 42 U.S.C. 4001- 4128, and 44 CFR Part 65. A hydraulic analysis of Boulder Creek was performed to incorporate the effects of overbank excavation between 17th Street and Broadway and improvements to the bridges at Arapahoe A venue, 17th Street, and Broadway, and to evaluate Canyon Boulevard Overflow and Boulder High School Overflow as hydraulically disconnected flooding sources affected by split flow from Boulder Creek. The analysis resulted in a revised delineation of the SFHA and modified BFEs along Boulder Creek, from approximately 360 feet upstream of 19th Street to approximately 425 feet upstream of 6th Street. To represent split flow from Boulder Creek, BFEs and SFHA delineations were determined for Canyon Boulevard Overflow, from approximately 230 feet upstream of 18th Street to just upstream of 6th Street,