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<br />The area between the floodway and IOO-year floodplain boundaries is <br />termed the floodway fringe. The floodway fringe encompasses the <br />portion of the floodplain that could be completely obstructed <br />without increasing the water-surface elevation of the lOO-year <br />flood by more than 1.0 foot at any point. Typical relationships <br />between the floodway and the floodway fringe and their significance <br />to floodplain development are shown in Figure 2. <br /> <br />Ie <br /> <br />100- YEAR FLOODPLAIN <br /> <br />.1 <br /> <br />'t( <br /> <br />FLOODWA Y <br />FRINGE <br /> <br />11( <br /> <br />FLOODWAY <br /> <br />FLOODWA Y <br />FRINGE <br /> <br />STREAM --.. <br />CHANNEL <br /> <br />FLOOD ELEVATION WHEN <br />CONFINED WITHIN FLOODWA Y <br /> <br /> <br />ENCROACHMENT <br /> <br />ENCROACHMENT <br /> <br />c <br /> <br /> <br />o <br />. <br />SURCHARGE * .. <br /> <br />----~--- <br /> <br />AREA OF FLOODPLAIN THAT COULD BE USED <br />FOR DEVELOPMENT BY RAISING GROUND <br /> <br />FLOOD ELEVATION BEFORE <br />ENCROACHMENT ON FLOODPLAIN <br /> <br />LINE AS IS THE FLOOD ELEVATION BEFORE ENCROACHMENT. <br />LINE CD IS THE FLOOD ELEVATION AFTER ENCROACHMENT. <br />.SURCHARGE IS NOT TO EXCEED 1.0 FOOT (FIA REQUIREMENT) OR LESSER AMOUNT IF SPECIFIED BY STATE. <br /> <br />Figure 2. Floodway Schematic <br /> <br />5.0 INSURANCE APPLICATION <br /> <br />For flood insurance rating purposes, flood insurance zone designations <br />are assigned to a community based on the results of the engineering <br />analyses. These zones are as follows: <br /> <br />Zone AE <br /> <br />Zone AE is the flood insurance rate zone that corresponds to the <br />lOO-year floodplair's that are determined in the Flood Insurance <br />Study by detailed methods. Whole-foot base flood elevations <br />derived from the detailed hydraulic analyses are shown at selected <br />intervals within this zone. <br /> <br />16 <br />