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. . . V. CORRECTED EFFECTIVE CONDITION HYDRAULIC ANALYSES The corrected effective analysis was necessary to: (a) combine the floodplain models for the Upper and Lower reaches into one model; and (b) correct any errors within the study limits that Wl~re discovered in the review ofthe duplicate effective condition models. Upper cmd Lower reach models were combined into one continuous model for the Cache la Poudre Riv~:r in order to eliminate several of the many regulatory models and allow for efficient tracking of split flows leaving the Upper Reach and reentering the river in the Lower Reach. Additionally, the left overbank of Cross Sections AS:228117, 229322, and AU:229477 were truncated where no flow existed during events less than the 100-year and flows were hydraulically disconnected during the 500-year event. These left overbank areas will be evaluated in detail in the existing condition step. 5.1 FEMA Analyses Table 5.1 lists the model names utilized in the duplicate effective analysis and the corresponding corrected effective FEMA model name. The purpose and originating study for each duplicate effective model combined to form the corrected effective model was previously listed and described in Table 3.1. Table 5.1 Duplicate and Corrected FEMA Model Names Duplicate Effective Corrected Effective DELQ06, DEUQ06, and DEU06 CE 1 OOQ06 DEL506 and DEU506 CE500Q06 DEIF06, DELlF06, and DEU1F06 CElFW06 DELINC06 CELINC06 The starting water surface elevations for all corrected effective models were: obtained from the Larimer County FIS restudy [FEMA, November 17, 1993]. The effective condition Mmming's n values were adopted for the corrected effective analysis. 5.1.1 Floodplain Analyses and Results The corrected effective 100-year floodplain analyses combined the DELQ06, DEUQ06, and the DEU06 models into the CEI00Q06 model. The effective modeling methodology had the eOFC2003-l0 Oxbow FINAL LOMR.doc 5.1 ANdERSON CONsulTiNG ENqiNEERS, INC.