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I I I I I I I I I I I I I I I I I I I RELOCATED FLOODWAY rn addition to mitigating the impact of the fill material placed within the floodway, the City may also want to consider relocating the regulatory floodway line through the Riverwood Estates area to an alignment along the bank line. This relocation would be consistent with the downstream floodway limits. Relocating the floodway would permit a large part of the subdivision to become compliant with the floodway regulations of the NFrp. The suggested relocated floodway line is shown on Sheet 1. The impact of moving the floodway on adjoining properties was determined for each of the suggested mitigation measures discussed in the previous section. The hydraulic model was changed in each case to consi der the floodway 1 i ne to be along the top of the ti ght bank through Riverwood Estates. For the excavated opposite bank condition, moving the floodway would cause a rise of up to approximately O.l-foot at Sections 28.4 and 28.8. This modest rise is attributed to both the narrower floodway and the computer model itself. Table 2 shows the computed elevations for the relocated floodway condition with the excavated opposite bank. Figure 4 also shows the resultant plotted profile {Fl. For the cleared and maintained river channel condition, the narrower floodway had no measurable effect on the floodway profile. The lost overbank conveyance was not significant to the floodway. No increase in the profile was computed. Table 3 shows the computed elevations and Figure 4 shows the profile (G). To relocate the floodway to the alignment shown on the map, the communi ty woul d need to support a floodway map revi si on request to FEMA. Additional information may be required by FEMA to approve such a request. Relocation appears to be very feasible. -17-