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. "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 Report", which is produced by local governments, state and federal agencies, special districts, or the private sector, and are used for floodplain management purposes and sometimes 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. CONSENT AGENDA ITEM 2.a Floodplain resolution number: FPR 05-585 Affected communities: Adams County, City of Brighton, City of Thornton, and City of Commerce City Name of study to be formally acted on: "Flood Hazard Area Delineation, South Platte River" (Adams County, Colorado) dated April 2005. Studied streams: South Platte River Technical Issues: The purpose and scope of the study is to provide local jurisdictions with a basis for management of the South Platte River floodplains and floodways through Adams County, and certain incorporated communities within the county, to help minimize threats from flooding to the public. Hydraulic modeling from the 2002 master plan was converted from HEC-2 to HEC-RAS. Letters of Map Revision (LOMRs) and other changes were incorporated into the new study. Floodways were analyzed based on 0.5 foot and 1.0 foot increases to the energy grade line based on assumed encroachment. Water surface profiles and floodplain delineations were carried out for the 100- and 500-year events. Community response: The Urban Drainage and Flood Control District (District) transmitted a letter to the CWCB dated April 25, 2005 requesting designation and approval of the subject 100-year floodplain information. The District Board of Directors also passed a resolution at their April 2005 meeting adopting the subject study. Staff findings: CWCB staff has determined that the subject 100-year detailed floodplain information for the South Platte River is in conformance with the CWCB's rules and regulations for floodplain designation and approval. The CWCB staff has reviewed the subject floodplain information, but has relied on the technical competence of the Urban Drainage and Flood Control District and their consulting engineer to complete the technical analyses and reviews. Staff endorses this study as containing the most current floodplain information available and urges the affected communities to utilize the study for land use decision-making purposes. Staff recommendation: Staff recommends that the Board: 1) designate and approve the 100-year detailed floodplain information contained in said report for the South Platte River, and 2) authorize staff to prepare a floodplain resolution to be signed by the Director and transmitted to the Urban Drainage & Flood Control District, Adams County, the City of Brighton, the City of Thornton, and Commerce City. This action is recommended in order to meet statutory requirements. Flood Protection. Water Project Planning and Financing. Stream and Lake Protection Water Supply Protection. Conservation Planning 2