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\'" profiles. 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 Ad...11li]1jstration 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. . 1) Consent Al!enda Item 2.a Floodplain resolution number: FPR 04-579 Affected communities: Gunnison County and the Town of Marble Name of study to be formally acted on: "Floodplain fuformation Report, Crystal River" dated August 2004, Studied streams: Crystal River Technical Issues: Icon Engineering under contract to the CWCB, and in cooperation with Gunnison County, conducted a detailed analysis of the Crystal River flood hazards within northern Gunnison County in the vicinity of Marble. The new study supercedes approximate floodplain information for the Town of Marble dated June 17, 1977 and covers approximately 4.5 miles of the Crystal River. A hydrologic analysis was performed to determine peak flow values for the study reach using a flood frequency analysis of streamflow gage data in the basin. Computed peak flow values at the gage sites were adjusted along the study reach as necessary using an accepted methodology provided by the USGS. Hydraulic analyses were performed using HEC-RAS to generate water surface profiles, which led to the delineation of 100-year and 500-year floodplains. A floodway was computed for this study assuming the FEMA minimum 1.0' rise criteria on the basis of equal conveyance reduction from each side of the floodplain. Community response: Gunnison County transmitted a letter to the CWCB dated October 15, 2004 requesting CWCB designation and approval of the subject report. The County was also actively involved with the scoping, development, and completion of the study. The County notified the CWCB by telephone that they were satisfied with the results and final product. CWCB staff concurs with the County's request for designation and approval of the study. Staff findings: CWCB staffhas determined that the subject 100-year detailed floodplain information for the Crystal River is conformance with the CWCB's rules and regulations for floodplain designation and . . Flood Protection. Water Project Planning and Financing. Stream and Lake Protection Water Supply Protection. Conservation Planning 2