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Report in Support of the Recertification of the <br />University of Colorado's Flood Control Levee <br />Page 1 <br />I. CONCLUSION <br />This report is an update of an earlier report by Leonard Rice Engineers, Inc. (LRE) submitted to <br />the Federal Emergency Management Agency (FEMA) on August 24, 1999 (see Appendix B). <br />FEMA certified the levee in 2000 after a thorough review of the material submitted by LRE in <br />1999. Our current report is submitted at this time because the University of Colorado's <br />(University) flood control levee (Levee) must be re- evaluated based on the recently completed <br />re- studies of the 100 -year flood and 100 -year flood plain of South Boulder Creek by the City of <br />Boulder (Boulder). Boulder submitted its hydrologic studies to FEMA for review in 2007, and it <br />submitted hydraulic studies and two versions of the flood plain in 2007 and 2008. <br />LRE has completed a review of the new information, and submits this report in support of the re- <br />certification of the Levee owned by the University. After considering the new hydrologic and <br />hydraulic data, the new flood -plain delineation, reviewing the 1999 and 2008 geotechnical <br />studies, the 1998 and 2009 erosion protection studies, and considering the maintenance activities <br />of the University (raising of portions of the Levee, and the reinforcing of the erosion - protection), <br />it is the professional opinion of the author of this report that the upstream reach of the Levee <br />(about 5,100 feet from station 101 +00 to 150 +70) satisfies all of the applicable criteria for <br />FEMA recognition of levees, which are spelled out at 44 C.F.R. Section 65.10 paragraphs (1) <br />through (6). The upstream reach of Levee: <br />• Ties into solid ground at its upstream and downstream ends; <br />• Has at least three and one -half feet of freeboard over the base flood elevations at the <br />upstream end of the Levee, and at least three feet of freeboard over the base flood <br />elevations for the remainder of the length [paragraph (b)(1)1; <br />• Has adequate erosion protection [paragraph (b)(3)]; <br />• Has sufficient embankment and foundation stability [paragraph (b)(4)]; <br />• Has sufficient resistance to seepage [paragraph (b)(4)]; <br />• Has sufficient resistance to settlement [paragraph (b)(5)]; <br />• Interior drainage is provided for without the use of any mechanized or electrical <br />equipment or facilities [paragraph (b)(6)]; <br />• Is owned and will be operated and maintained by a responsible State Entity [paragraphs <br />(c) and (d)]; and <br />• Has an acceptable operation and maintenance plan [paragraphs (c) and (d)]. <br />II. BACKGROUND AND TIME LINE <br />• The Levee is an existing flood control structure that was designed in 1979 and <br />constructed in 1980. It is clearly identifiable as a land form on topographic mapping <br />prepared from aerial photographs taken in November 1980. <br />• It was recognized as an effective flood control structure in a subsequent study of the <br />flood plain completed by engineering firm of Greenhorne and O'Mara, Inc. (G &O) in a <br />1986 flood hazard delineation study for the Urban Drainage and Flood Control District <br />(UDFCD), Boulder, and Boulder County. <br />© Leonard Rice Engineers, Inc. June 2009 — 207FIP05 <br />