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L . methods and results. CWCB staff concurs with the UDFCD request for designation and approval of the study. Staff findings: CWCB staff has determined that the subject 100-year detailed floodplain information for the studied stream reaches is conformance with the CWCB's rules and regulations for floodplain designation and approval. The CWCB staff has relied on the technical competence of Olsson Associates, who produced the study, and the technical review by the UD&FCD and local sponsors, and therefore endorses this study as containing the most current floodplain mapping available and urges the affected communities to adopt said study for land use regulation purposes pursuant to statutory authority. Staff recommendation: Staff recommends that the Board: I) designate and approve the 100-year detailed floodplain information contained in said report within Jefferson County and the City of Littleton and 2) authorize staff to prepare a floodplain resolution to be signed by the Director and transmitted to the UD&FCD, Jefferson County, the City of Littleton, and to FEMA. This action is recommended in order to meet statutory requirements. . 2) Consent Al!enda Item 2.b Floodplain resolution number: FPR 06-589 Affected communities: Adams County Name of study to be formally acted on: "Flood Hazard Area Delineation, Clear Creek (Adams County)" dated December 2005. Studied streams: Clear Creek Technical Issues: This report was authorized by the Urban Drainage and Flood Control District (UD&FCD), the Colorado Department of Transportation (CDOT), and Adams County to update flood hazard data for the subject stream reaches, to produce new plan and profile information for the 100-year floodplains, and to define floodways for the subject stream reaches. The total study area includes almost 575 square miles of drainage area originating in the central Colorado mountains near Loveland Pass. The hydraulic analysis only includes the reach from the Adams/Jefferson county line (Sheridan Boulevard) to the mouth of Clear Creek at the South Platte River, The flood discharges used in this report were computed and supplied by the Omaha District of the U.S. Army Corps of Engineers and were incorporated into a previously designated report entitled "Flood Hazard Area Delineation, Clear Creek, Adams and Jefferson County", prepared by Gingery Associates, Inc" and dated November 1979 (Designation # 155). Hydraulic analyses were carried out using the U.S. Army Corps of Engineers River Analysis System (HEC-RAS) based on steady flow conditions. Floodways were computed assuming both 0.5' and 1.0' rise criteria. Water surface elevations are updated based on revised hydrologic conditions based on areas of split flow, more recent topographic mapping, and changed topographic features. The CWCB and the UD&FCD plans to include this new information within the Adams County Digital Flood Insurance Rate Map that is now in progress. Community response: The UD&FCD transmitted a letter to the CWCB dated February 8, 2006 and Adams County transmitted a letter dated February 12, 2006 requesting CWCB designation and approval of the subject report. The UD&FCD also sent follow-up emails to staff regarding the proposed designation action. The UD&FCD staff worked directly with the affected communities during the course of the study and received input and endorsement for the study methods and results. CWCB staff concurs with the UDFCD request for designation and approval of the study. Staff findings: CWCB staff has determined that the subject 100-year detailed floodplain information for the studied stream reaches is conformance with the CWCB's rules and regulations for floodplain designation and approval. The CWCB staff has relied on the technical competence of the study contractor, Ayres Associates, and the technical review by the UD&FCD and local sponsors, Staff . Flood Protection. Water Project Planning and Financing. Stream and Lake Protection Water Supply Protection. Conservation Planning 3