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' The three surveyed cross - sections, the one surveyed cross - sections transferred to reaches other <br />than the reach where they were surveyed, the two cross - sections that were hybrids of map cross- <br />' sections and field data, and the one cross - section which used FEMA depths from an upstream <br />location are graphically represented in Figures 7A -F. Example rating curves were prepared for <br />the three field - surveyed cross - sections. They are presented in Plates 10 -12, after the floodplain <br />' maps. <br />0 <br />0 <br />C <br />n <br />n <br />4.5 Delineating Flood Boundaries <br />The calculated flood depths for the various stream reaches were first plotted on the quadrangle <br />maps at the cross - section locations. The resulting floodplain widths were compared to the <br />floodplain widths on the cross - section plots. The floodplain boundaries between the cross - <br />sections were then approximated by delineating flood depth contours and interpreting the <br />relationship between those flood depth contours and the ground contours. Consideration was <br />given to the slope within each reach. The finalized information was displayed on the USGS 7.5' <br />quadrangle maps (scale of 1" = 2,000'). A table identifying the quadrangle maps used in each <br />plate and the map scale is given in Figure 8. The location of each floodplain map plate is shown <br />in Figure 9, and the floodplain maps are shown in Plates 1 -9. <br />19 <br />