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The floodways for this study were computed on the basis of equal conveyance reduction from'each side of the flood plain. The results of these computations are tabulated at selected cross sections for each stream segment studied in detail (Table 2 ) . No floodway was developed on Northfield Creek below Devonshire Boulevard because all flows are contained within the channel, In cases where the 100-year boundary and the floodway are close together, only the floodway has been shown. As shown on the Flood Boundary and Floodway Map, the floodway boundaries were determined at cross sections; between cross sections, the boundaries were interpolated. Parts of the floodways are outside the county boundaries and are not shown. " The area between the floodway and the boundary of the 100-year flood is termed the floodway fringe. The floodway fringe thus encompasses the portion of the flood plain that could be completely obstructed without increasing the water-surface elevation of the 100-year flood more than 0.5 foot at any point, Typical relationships between the floodway and the floodway fringe and their significance to flood plain development are shown in Figure 13. . I- 100-YEAR FLOOD PLAIN -I FLOOOWAY" FRINGE FLOODWAY FLOOOWAY FRINGE STREAM CHANNEL FLOOD ELEVATION WHEN CONFINED WITHIN FLOODWAY . AREA OF FLOOD PLAIN THAT COULD BE USED FOR DEVELOPMENT BY RAISING GROUND SURCHARGP FLOOD ELEVATION BEFORE ENCROACHMENT ON FLOOD PLAIN LINE AS 1$ THE FLOOD ELEVATION BEFORE ENCROACHMENT. LINE CD IS THE FLOOD ELEVATlON AFTER ENCROACHMENT. 'SURCHARGE IS NOT TO ExceED 1.0 FOOT (FIA REQUIREMENT) OR LESSER AMOUNT IF SPECIFIED BY STATE. Figure 13. Floodway Schematic 19