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<br />powers. Approximate floodplain information means floodplain information prepared using a <br />significantly reduced leyel of detail to arriye at a hazard delineation without water surface profiles. <br />CWCB staff performs teclmical reyiews on the following types of reports and maps for approyal and <br />designation by the Board: <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 haye an <br />accompanying report. Note: For all FHBM designations, the CWCB staff will perform (in-house <br />or by contract with a consultant) hydrologic analyses. <br />. "Floodplain Information Reports", which are produced by local goyemments, state and federal <br />agencies, special districts, or the priyate sector, and are used for floodplain management purposes <br />and usually adopted by FEMA for use in Flood Insurance Rate Map reyisions. <br />. Various hydrology studies and related floodplain studies (community-wide or site specific) that <br />depict 100-year floodplain information that is useful for floodplain management purposes. <br />. "Floodplain Information" is a generic term used to describe any of the aboye types of reports <br />and! or maps in the CWCB' s "rules and regulations. . ." <br />. "Floodplain Resolution" is a formal document prepared by CWCB staff describing the Floodplain <br />Information that is to be designated and approyed by the Board. <br /> <br />1) Al!enda Item 3.a <br />Floodplain resolution number: FPR 01-560 <br />Affected communities: Town of Ayon <br />Name of study to be fonnally acted on: "Flood Insurance Rate Map, Town of Ayon, Eagle COWlty, <br />Colorado" dated August 1987. - prepared by the Federal Emergency Management Agency. <br />Studied streams: Currently, there are no floodplains shown on the map and the entire Town Limits <br />are shown in Zone D (area of possible but undetermined flood hazard). Because of this ambiguous <br />determination by FEMA, an update of the map with new approximate floodplains for those streams <br />within the Town Limits will be generated. <br />Technical issues: The streams within the Town of Ayon for which approximate floodplains will be <br />deyeloped include June Creek, Beayer Creek, Metcalf Creek, Buck Creek and the Eagle Riyer. There <br />has been some deyelopment within these drainage areas. There are some complicating factors due to <br />culyert crossing and Interstate 70. It is possible to utilize the CWCB's regional regression equations <br />for the hydrology calculations if deemed appropriate; otherwise peak flows will be computed by other <br />means. In addition, based on ayailable GIS information, the Town limits do not appear to haye <br />changed since the study. This will be yerified with the Town. It is likely that drainage reports exist for <br />some of the tributary creeks near deyelopment. These reports will be consulted to obtain hydrology <br />and approximate floodplains. The FEMA maps do not correctly identify the Metcalf Ditch, which <br />appears to diyert all water out of Metcalf Creek. This will need to be correctly labeled and the impacts <br />of the ditch on drainage through the Town determined. <br /> <br />Flood Protection. Water Project Planning and Financing. Stream and Lake Protection <br />Water Supply Protection. Conservation Planning <br /> <br />2 <br />