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GREG ROUSH <br />GREGG TEN EYCK <br />JON FORD <br />ERIN WILSON <br />LEONARD RICE ENGINEERS, INC. EDARMBRUSTER <br />2000 CLAY STREET, SUITE 300, DENVER, COLORADO 80211-5119 LESLIE BOTHAM <br />DENNIS MCGRANE <br />(303) 455 -9589 ♦ (800) 453 -9589 ♦ FAX (303) 455-0115 .JANET WILLIAMS <br />RICK PARSONS <br />June 5, 2009 <br />Mr. Dave Jula <br />Michael Baker Jr., Inc. <br />355 Union Boulevard, Suite 200 <br />Lakewood, CO 80228 <br />RE: Engineering Report Summarizing the Field Surveys and Engineering Studies in Support <br />of the Recognition of the University of Colorado's Flood Control Levee, South Boulder Creek <br />Dear Mr. Jula: <br />On behalf of the University of Colorado and the Flatiron Companies, and in response to <br />Boulder's request for information to support FEMA's recognition of the University's Levee we <br />submit the accompanying report and eight appendices. The existing Levee is located at the <br />western edge of the 100 -year flood plain of South Boulder Creek, in Section 9, Township 1 <br />South, Range 70 West, of the 6 th P.M., in Boulder County, Colorado. It was recognized by <br />FEMA in 2000. It needs to be recognized anew because the City of Boulder completed a detail <br />restudy of the 100 -year flood hydrology and hydraulic restudies of the 100 -year flood plain. The <br />new studies are under review at this time by FEMA and they will change the base flood plain. <br />The new flood levels are higher in some reaches for the Levee, and the flood velocities against <br />the Levee are higher than indicated by earlier studies. <br />The Levee has provided a significant level of protection for Boulder since its construction in <br />1980. It has been recognized as being effective in several engineering studies (Greenhorne & <br />O'Mara, Inc. in 1986, Love and Associates, Inc. and Taggart Engineering Associates, Inc. in <br />1998) and by FEMA in its 1990 Flood Insurance Rate Maps for Boulder and Boulder County. In <br />response to Boulder's current hydraulic studies by DHI Water Environment Health with input <br />from Alan Taylor Consulting, and as part of its adopted Operation and Maintenance plan, the <br />University caused two sections of the Levee to be raised to maintain the required freeboard, and <br />the rip rap of one section was replaced so that the required erosion protection could be <br />maintained. <br />We have evaluated the Levee in light of the criteria specified at 44 CFR 65.10, and believe that <br />its upstream reach satisfies all of the criteria. We believe that FEMA can recognize the Levee so <br />that the 100 -year flood plain submitted by Boulder can be adopted and regulated as the new Base <br />Flood Plain. <br />The report includes engineering studies and reports by Leonard Rice Engineers, Inc., <br />CTL /Thompson, Inc., Ayres Associates, Inc., AMEC Earth and Environmental, Robert M. Sayre, <br />P.L.S., and Love and Associates, Inc. In the interest of reducing the impact on our environment, <br />we are sending you one black- and -white paper copy of the report and appendices. The <br />WATER RIGHTS ♦ GROUND WATER ♦ PERMITTING ♦ WATER RESOURCE PLANNING ACEC <br />