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<br />. <br /> <br />. <br /> <br />. <br /> <br />5.1.2 One-Foot Floodway Analysis and Results <br /> <br />The duplicate effective models DEIF06, DELIF06, and DEUIF06 were combined to <br />form the CEIFW06 model. No adjustments to duplicate effective floodway encroachment <br />stations were made during the corrected effective analysis. <br />Table 5.3 presents a comparative summary of the duplicate effective and corrected <br />effective one-foot rise floodway results. Within the current study limits, the corrected effective <br />computed floodway widths match the duplicate effective floodway widths everywhen:: except at <br />the upstream side of the Lemay Avenue Bridge (Cross Section AM:221702) where a I-foot <br />decrease was noted. The one-foot decrease is a result of lower without floodway water surface <br />elevations in the corrected effective condition than in the duplicate effective condition. <br />All corrected effective surcharge values meet the one-foot rise value promulgated by <br />FEMA. The corrected effective one-foot rise floodway delineation is shown on Sheets 2A and <br />2B. The HEC-2 input/output for the corrected effective one-foot rise floodway ~malysis is <br />provided in the Appendix G. A digital copy of the HEC-2 models utilized for the current study <br />is provided on the disk included with this report. <br /> <br />5.2 COFC Analyses - Tenth-Foot Floodway Analysis and Results <br /> <br />The COFC analyses was required to update the tenth-foot floodway in the corrected <br />effective condition. <br />The duplicate effective model DETFW06 was renamed to create the CETFW06 model. <br />No adjustments to duplicate effective floodway encroachment stations were made during the <br />corrected effective analysis. The 'with' and 'without' discharges in the CETFW'06 model <br />remained the same as in the effective (DETFW06) model. Truncation of the left overbank of <br />Cross Sections AS:2281 17, 229322, and AU:229477 was the only change made to thi~ effective <br />model during the corrected effective step. <br />Table SA presents a comparative summary of the duplicate effective and corrected <br />effective tenth-foot rise floodway results. Within the current study limits, the corrected effective <br />computed floodway widths match the duplicate effective floodway widths everywhere. All <br />corrected effective surcharge values meet the tenth-foot rise value promulgated by COFC except <br />where larger surcharges were adopted by the COFC in the effective condition. Since the <br />corrected effective tenth-foot rise floodway matched the effective tenth-foot rise floodway, the <br />corrected tenth-foot floodway was not re-delineated. The HEC-2 input/output for the corrected <br />effective tenth-foot rise floodway analysis is provided in the Appendix G. A digital copy of the <br />HEC-2 models utilized for the current study is provided on the disk included with this report. <br /> <br />eOFC2003-1O Oxbow FINAL LOMR,doc <br /> <br />5.6 <br /> <br />ANdERSON CONsulTiNG ENGiNEERS, INC. <br />