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CWCB staff performs technical reviews on the following types of reports and maps for approval and designation by the Board: . "Flood Insurance Study" (FIS), which is produced by the Federal Emergency Management Agency (FEMA) and used for floodplain management, regulation, and insurance purposes. . "Flood Insurance Rate Map" (FIRM), which is produced by FEMA and used for floodplain management, regulation, and insurance purposes. A FIRM may be published with or without an associated hydrologic and hydraulic report. . "Flood Hazard Boundary Map" (FHBM), which was produced by the Federal Insurance Administration and are used for floodplain management, regulation, and insurance purposes. An FHBM usually depicts approximate floodplain boundaries only, and does not have an accompanying report. Note: For all FHBM designations, the CWCB staff will perform (in-house or by contract with a consultant) hydrologic analyses. . "Floodplain Information Reports", which are produced by local governments, state and federal agencies, special districts, or the private sector, and are used for floodplain management purposes and usually adopted by FEMA for use in Flood Insurance Rate Map revisions. . Various hydrology studies and related floodplain studies (community-wide or site specific) that depict 100-year floodplain information that is useful for floodplain management purposes. . "Floodplain Information" is a generic term used to describe any of the above types of reports and! or maps in the CWCB' s "rules and regulations. . ." . "Floodplain Resolution" is a formal document prepared by CWCB staff describing the Floodplain Information that is to be designated and approved by the Board. 2) Al!enda Item 3 Floodplain Resolution Number: FPR 03-573 Affected Community: Arapahoe County, City and COWlty of Denver, Greenwood Village, Cheny Hills Village, and City of Littleton Name of study to be fonnally acted on: "Flood Hazard Area Delineation, Little Dry Creek & Tributaries" dated August 2003. Studied Streams: Little Dry Creek, Greenwood Gulch, Blackmer Gulch, Prentice Gulch, and Willow Creek Technical Issues: This report is part of a study authorized by the Urban Drainage and Flood Control District (UDFCD) in conjunction with 7 local sponsoring agencies, and documents the flood hazards for Little Dry Creek and its tributaries. The study area for Little Dry Creek begins at South Clarkson Street in Englewood and extends upstream to the outlet of Holly Dam in the new City of Cente1l11ial. The total drainage area of the subject watershed is approximately 25 square miles. The study utilized previously prepared 100-year hydrologic information published in a 1986 report by McLaughlin Water Engineers (MWE) which was reviewed and approved by FEMA. Hydrographs for the 10-, 50-, and 500-year events were generated by WRC Engineering using the CUHP/SWMM models using the reproduced WME models as a basis. Water surface profiles were defmed for the 10-, 50-, 100-, and 500-year storm events, while floodplain delineations were prepared only for the 10- and 100-year events. Floodway computations were completed assuming a 0.5-foot and 1.0 rise water surface due to floodplain encroachment. Community response: The UDFCD transmitted a letter to the CWCB dated September 2, 2003 requesting CWCB designation and approval of the subject report. The Board of the UDFCD at their Flood Protection. Water Project Planning and Financing. Stream and Lake Protection 2 Water Supply Protection. Conservation Planning