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<br />. <br /> <br />. <br /> <br />. <br /> <br />The input/output HEC-2 reports for the duplicate effective floodplain models are <br />provided in Appendix G. A digital copy of the HEC-2 models utilized for the current study is <br />provided on the disk included with this report. <br /> <br />4.1.2 One-Foot Floodway Analysis and Results <br /> <br />FEMA administers a one-foot rise floodway criterion on the Cache la Poudre River. Thus, the <br />one-foot rise floodway analysis was replicated for the duplicate effective analysis. By definition, <br />the duplicate effective floodway models were re-run in HEC-2 without any changes made to the <br />models. The same starting water surface elevations and roughness coefficients utilized in the <br />effective analysis were also utilized in the duplicate effective analysis. It should be notled that the <br />encroached discharges at Cross Sections 228117, 227437, 227397, 226167, and 224597 were <br />increased over the unencroached discharges; thereby confirming that a separate floodway was not <br />required on the LINC Divided Flow Path. Table 4.3 presents a summary of the effiective and <br />duplicate effective one-foot rise floodway results for the study reach. <br />Within the study reach, results of the duplicate effective one-foot rise floodway analysis matched <br />the results published in the FIS and LOMRs. <br />Results of the duplicate effective one-foot rise floodway analysis also matched the <br />effective one-foot floodway delineation shown on the workmaps. Due to the close match with <br />the effective floodway data and delineation, it was concluded that the duplicate effective one- <br />foot rise floodway models used as the basis for the current study effectively reproduce the results <br />from the 1996 FIS, the 1999 LOMR, and the 2005 Removal Action LOMR. The input/output <br />HEC-2 reports for the duplicate effective floodway models are provided in Appendix G. A <br />digital copy of the HEC-2 models utilized for the current study is provided on the disk included <br />with this report. <br /> <br />4.2 COFC Analyses - Tenth-Foot Floodway Analysis and Results <br /> <br />The effective COFC models for the current study on the Cache la Poudre River were <br />previously listed and described in Table 3.3. Table 4.4 lists the model names utilized in the <br />duplicate effective analysis and the corresponding effective COFC model. <br /> <br />eOFC2003-l0 Oxbow FINAL LOMR.doc <br /> <br />4.5 <br /> <br />ANdERSON CONsulTiNG ENqiNEERS, INC. <br />