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I I I I I I I I I I I I I I I I I I I The floodway presented in this study was computed on the basis of equal- conveyance reduction from each side of the floodplain. Fioodway widths were computed at cross sections. Between cross sections, the floodway boundaries were interpolated. The results of the floodway computations are tabulated for selected cross sections, as shown on Plates 2 and 3. In cases where the floodway and 100-year floodplain boundaries are either close together or collinear, only the floodway boundary is shown. The area between the floodway and 100-year floodplain boundaries is termed the floodway fringe. The floodway fringe encompasses the portion of the floodplain that could be completely obstructed without increasing the WSEL of the 100-year flood more than .\.o foot at any point. Typical relationships between the floodway and the floodway fringe and their significance to floodplain development are shown below. Figure 3: Floodway Schematic ,. 100-YEAR FLOODPLAIN FLOODWAY I FLOODWAY FRINGE SlREAt.I CHANNEL LOODWAY FRINGE FLOOO ELEVATION WHEN CONFINED 1MlHIN FLOODWAY ENCROACHMENT AREA OF FLOODPLAIN THAT COULD BE USED fOR DEVELOPMENT BY RAISING GROUND FLOOD ELEVATION BEFORE ENCROACHMENT ON FLOODPLAlN LINE AB IS THE "-000 ELEVAlION BEFORE ENCROIOiWENT. LINE CD IS THE R...OOD El..EVA110N AFTER EN~OACHWENT. -SUACHARCE IS NOT TO EXCEED 1.0 FOOT (AA REQU1REWEN1) OR LESSER At.lOUNT IF SPECIFIED BY THE STATE. 5.0 LOCATION OF DATA Information pertinent in the preparation of this study can be obtained by contacting the Colorado Water Conservation Board, 1313 Sherman Street, Room 721, Denver, Colorado 80203. This study may also be viewed and printed online at the CWCB's digital Water Resource Information Center. Visit us at www.cwcb.state.co.us. ICON Engineering, Inc. August 2004 9