FLOOD09787

• County: Delta
• Community: Cedaredge
• Stream Name: Surface Creek
• Basin: Gunnison
• Title: Floodplain Delineation for Cedaredge, Colorado
• Date: 12/8/2003
• Prepared For: CWCB
• Prepared By: Gared Grube
• Floodplain - Doc Type: Floodplain Report/Masterplan

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0.5 were entered in for all upstream and downstream locations of the cross-sections. 0.3 and 0.5
for all bridges. and 0.6 and 0.8 for all culverts respectfully. The water surface elevations were
calculated with HEC-RAS (Appendix D). The resulting surface elevations were exported back
into ArcView using HEC-GeoRAS and were convened into GIS data.

5.5 Floodplain Delineation Maps

After HEC-RAS was used to compute the surface water elevations for the 1000year peak flow.
the post-processing steps of the HEC-GeoRAS was used to produce the floodplain delineation.
These delineations were then superimposed over aerial images of the study area. The figures
below show the floodplain maps that were created for Surface Creek.

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