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Report in Support of the Recertification of the <br />University of Colorado's Flood Control Levee <br />Page 7 <br />freeboard, erosion protection, interior drainage, and public ownership. Even though it has not <br />been studied specifically, it is believed that the Levee also satisfies the strength and resistance to <br />seepage criteria. The Levee may not meet the criteria in the areas of maintenance and vegetation <br />on the face of the Levee. <br />VI.3. Downstream Reach <br />The third reach is the most downstream reach of the Levee. It extends from the point where the <br />base flood plain again comes into contact with the Levee (station 88 +00) to its downstream limit <br />where the Levee ties into the east -bound on -ramp of US Highway 36 (station 75 +50). See <br />Figures 9 and 11. The Levee is overtopped by the 100 -year flood in this reach. This reach of <br />Levee is also included and described in this report, but not all of FEMA's criteria for recognition <br />are satisfied at this time. The Levee satisfies the internal- drainage and public- ownership criteria. <br />Even though it has not been studied specifically, it is believed that the Levee also satisfies the <br />strength and resistance -to- seepage criteria. However, it does not satisfy the criteria with regard <br />to freeboard, and it may not satisfy the criteria in the areas of maintenance and vegetation on the <br />face of the Levee. It has not been determined whether or not the Levee satisfies the erosion <br />protection requirement. <br />VI.4. Upstream Reach Recognizable by FEMA <br />Considering the opinions of the professional engineers that conducted the geotechnical and <br />erosion - protection studies (in 1998 and 2008- 2009), the professional land surveyor that <br />conducted the as -built survey, and considering our own investigations, it is the professional <br />opinion of the author of this report, that the upstream reach of Levee continues to satisfy all of <br />the applicable FEMA criteria for recognizing Levees, which criteria are spelled out at 44 C.F.R. <br />Section 65.10 paragraphs (1) through (6). The official 100 -year flood plain can be delineated <br />based on its being in place. <br />The middle and downstream reaches are not recognizable, and /or do not need to be recognized <br />by FEMA at this time for the following reasons: <br />• In the middle reach, the flood plain is controlled by a land mass (naturally occurring high <br />ground) so it does not come in contact with the Levee at all. <br />• The middle and downstream reaches of the Levee do not satisfy all of the applicable <br />FEMA criteria for recognition of levees. <br />• Trees and vegetation have not been removed from the face of the Levee in the middle and <br />downstream reaches. <br />• The 2 -D hydraulic study by Boulder indicates that the downstream reach is overtopped <br />during the 100 -year flood, so the freeboard criterion cannot be satisfied in this area <br />without increasing the height of the embankment. <br />The three reaches of Levee are summarized on the following tables. <br />© Leonard Rice Engineers, Inc. June 2009 — 207F1P05 <br />