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, e e e 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 1 OO-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 docwnent prepared by CWCB staff describing the Floodplain Information that is to be designated and approved by the Board. 1) Consent Aeenda Item 2a Floodplain resolution number: FPR 02-567 Affected communities: City of Holyoke and Philips County Name of study to be formally acted on: "Hydrologic and Hydraulic Analyses, Frenchman Creek, Holyoke, Colorado" dated August 9, 2002 Studied streams: Frenchman Creek Technical issues: The subject report was prepared by the U. S. Army Corps of Engineers, Kansas City District, in cooperation with the City of Holyoke and Philips County (affected communities), and the Colorado Water Conservation Board. The Corps of Engineers utilized recent topographic base mapping that was produced using state of the art LIDAR technology yielding 2 foot contour intervals. A new hydrologic analysis was performed for the Frenchman Creek watershed using the HEC-HMS rainfall- runoff model that was calibrated to results from various other methodologies. The peak flows from the model were reviewed by CWCB staff and others for reasonableness, and were accepted by the affected communities as well. Finally, the new hydrology was utilized in a HEC-RAS model to compute water surface profiles which lead to delineation of the revised floodplain for Frenchman Creek. Community response: The CWCB staff has been intricately involved with the development of the floodplain infonnation for Frenchman Creek and has met numerous times with the City, County and the Corps of Engineers during the development and completion process of the study. The City and County are in agreement with the results of the study and are very supportive of having the new information become designated and approved by the Board. Staff findings: The subject detailed floodplain information report for Frenchman Creek revises an existing outdated study that was completed approximately 20 years ago. The new report utilizes state of the art hydrologic and hydraulic modeling techniques and depicts the best available floodplain delineation for the City of Holyoke and adjacent portions of unincorporated Phillips County. CWCB staff is confident that all Flood Protection. Water Project Planning and Financing. Stream and Lake Protection Water Supply Protection. Conservation PlalUling 2