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<br /> <br />powers. Approximate floodplain infonnation means floodplain infonnation prepared using a <br />significantly reduced level of detail to arrive at a hazard delineation without water surface profiles. <br />CWCB staffperfonns teclmical reviews on the following types of reports and maps for approval and <br />designation by the Board: <br /> <br />. <br /> <br />. "Flood Insurance Study" (FIS), which is produced by the Federal Emergency Management Agency <br />(FEMA) and used for floodplain management, regulation, and insurance purposes. <br />. "Flood Insurance Rate Map" (FIRM), which is produced by FEMA and used for floodplain <br />management, regulation, and insurance purposes. A FIRM may be published with or without an <br />associated hydrologic and hydraulic report. <br />. "Flood Hazard Boundary Map" (FHBM), which was produced by the Federal Insurance <br />Administration and are used for floodplain management, regulation, and insurance purposes. An <br />FHBM usually depicts approximate floodplain boundaries only, and does not have an <br />accompanying report. Note: For all FHBM designations, the CWCB staff will perfonn (in-house or <br />by contract with a consultant) hydrologic analyses. <br />. "Floodplain Infonnation Reports", which are produced by local governments, state and federal <br />agencies, special districts, or the private sector, and are used for floodplain management purposes <br />and usually adopted by FEMA for use in Flood Insurance Rate Map revisions. <br />. Various hydrology studies and related floodplain studies (community-wide or site specific) that <br />depict 100-year floodplain infonnation that is useful for floodplain management purposes. <br />. "Floodplain Infonnation" is a generic tenn used to d~scribe any of the above types of reports and/or <br />maps in the CWCB's "rules and regulations..." <br />. "Floodplain Resolution" is a fonnal document prepared by CWCB staff describing the Floodplain <br />Infonnation that is to be designated and approved by the Board. <br /> <br />. <br /> <br />1) Al!enda Item 3 <br />Floodplain resolution number: FPR 03-570 <br />Affected communities: Arapahoe County, Douglas County, City of Aurora, City of Centennial, Town of <br />Parker <br />Name of study to be formally acted on: "Flood Hazard Area Delineation, Cherry Creek Corridor, <br />Reservoir to Scott Road" dated May 2003 - prepared by the Urban Drainage and Flood Control District. <br />Studied streams: Cherry Creek <br />Technical issues: The Cherry Creek watershed is approximately 54 miles long and averages 10 miles in <br />width. The headwaters of Cherry Creek originate on the north side of the Palmer Divide and the creek <br />empties into the South Platte River in Denver at an area known as Confluence Park. The watershed <br />above the reservoir is 386 square miles and includes portions of Arapahoe, Douglas and EI Paso Counties. <br />The lower portions of the study reach are highly developed in areas and contain infrastructure, residential <br />development, and commercial development. A number of significant flood events have been documented <br />along Cherry Creek during recorded history within the region. Peak flood flows used for the study were <br />derived from the most recent FEMA PIS (1996) and were based on analyses of stream gages on Cherry <br />Creek located at Franktown and Parker. The 100-year peak flow at the downstream study limit is <br />reported to be 51,000cfs. Hydraulic analyses were carried out using the U.S. Anny Corps of Engineers <br />River Analysis System software known as HEC-RAS. Plood profiles for the 10-, 50-, 100-, and 500-year <br />events were computed. <br /> <br />. <br /> <br />Flood Protection. Water Project Planning and Financing. Stream and Lake Protection <br />Water Supply Protection. Conservation Planning <br /> <br />2 <br />