Laserfiche WebLink
<br />The floodways presented in this study were computed on the basis <br />of equal conveyance reduction from each side of the flood plain. <br />The results of these computations are tabulated at selected cross <br />sections for each stream segment for which a floodway is computed <br />(Table 2). <br /> <br />'"( <br /> <br />As shown on the Flood Boundary and Floodway Map (Exhibit 2), the <br />floodway boundaries were determined at cross sections; between <br />cross sections, the boundaries were interpolated. In cases where <br />the floodway and lOa-year flood boundaries are close together, <br />only the floodway boundary has been shown. <br /> <br />"- <br /> <br />The area between the floodway and the boundary of the lOa-year <br />flood is termed the floodway fringe. The floodway fringe thus <br />encompasses the portion of the flood plain that could be completely <br />obstructed without increasing the water-surface elevation of the <br />lOa-year flood more than 1.0 foot at any point. TYrical relationships <br />between the floodway and the floodway fringe and their significance <br />to flood plain deve~opment are shown in Figure 2. <br /> <br />,,. <br /> <br />Ie <br /> <br />100-YEAR FLOOD PLAIN <br /> <br />~I <br /> <br />FLOODWAY <br />FRINGE <br /> <br /> <br />FLOODWAY <br /> <br />FLOODWAY <br />FRINGE <br /> <br />,,,," <br /> <br />STREAM <br />CHANNEL <br /> <br /> <br />FLOOD ELEVATION WHEN <br />CONFINED WITHIN FLOODWAY <br /> <br />ENCR~MENT ~ <br /> <br />. <br />i <br />. <br /> <br />ENCROACHMENT <br />-,-- <br /> <br /> <br />.. <br /> <br />-L <br />AREA OF FLOOD PLAIN THAT COULD <br />BE USED FOR DEVELOPMENT BY <br />RAISING GROUND <br /> <br /> <br />FLOOD ELEVATION <br />BEFORE ENCROACHMENT <br />ON FLOOD PLAIN <br /> <br />LINE AB 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 />'" <br /> <br />t. <br /> <br />8 <br />