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WHEREAS, Section 37-60-106(1)(c), Colorado Revised Statutes, directs the Colorado Water Conservation Board to designate and approve storm or floodwater runoff channels or basins and to make such designations available to legislative bodies ofloca1 jurisdictions; and CONSISTENCY WITH PREVIOUS FLOODPLAIN STUDIES WHEREAS, the detailed floodplain information for Murphy Creek revises and is, therefore, inconsistent with the detailed and approximate floodplain information for Murphy Creek contained in Resolutions No. 49, 117,277,334,353,354.01,405, 507, 508, 509, and 538; and WHEREAS, all Letters of Map Amendments (LOMA's), Letters of Map Revisions Based on Fill (LOMR-F's), and Letters of Map Revisions (LOMR's) approved by FEMA prior to August 2006, but not designated by the CWCB were based on floodplain information superseded by, and therefore inconsistent with, the new report dated August 2006 for the City of Aurora and Arapahoe County; and COMPLIANCE WITH CWCB TECHNICAL STANDARDS WHEREAS, said new report is based on infonnation gathered and assembled for the existing drainage systems including hydraulic structures, channels, and topography; and WHEREAS, said new report is based on hydrologic information developed using the Colorado Urban Hydrograph Procedure 2005, and the Environmental Protection Agency Storm Water Management Model, Version 5.0; and WHEREAS, water surface elevations for the 10- and 100-year flood frequencies for the studied stream reach were computed for said new report using the U.S. Army Corps of Engineers HEC-RAS hydraulic model, Version 3.1.3; and WHEREAS, floodway limits for the 100-year flood frequency assuming both a I-foot maximum rise, as defined by FEMA, and a 0.5 foot maximum rise, as defined by UDFCD, were computed for said new report using the U.S. Army Corps of Engineers HEC-RAS hydraulic model, Version 3.1.3; and WHEREAS, the detailed 100-year floodplain and floodway information for Murphy Creek in said new report meets the requirements listed under the Board's "Rules and Regulations for Regulatory Floodplains in Colorado" (2 CCR 408-1); and WHEREAS, the City of Aurora, Arapahoe County, and the Urban Drainage and Flood Control District should continue to regulate new development and construction in floodplain areas on a case- by-case basis based on the information presented in said new report, or based on the best available floodplain information that is accessible to the City, the County, and the District; and DESIGNATION. APPROVAL AND RESCISSION ACTION 3