FLOOD10388 ‎(2)‎

• County: Statewide
• Stream Name: Gunnison River
• Title: Floodplain Information Report - Volume 3 - Gunnison River from Delta to the Confluence of the Colorado River
• Date: 5/1/1995
• Prepared For: Recovery Implementation Program for Endangered Fish Species in the Upper Colo
• Prepared By: CWCB
• Floodplain - Doc Type: Floodplain Report/Masterplan

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methodologies used by state and federal agencies in performing detailed analyses, except that
there is no balancing of energy from one cross-section to the next.

The three surveyed cross-sections, the two surveyed cross-sections transferred to reaches other
than the reach where they were surveyed, and the three cross-sections that were hybrids of map
cross-sections and field data are graphically represented in Figures 7A-7H. Example rating
curves were prepared for the three field-surveyed cross-sections. They are presented in Plates
8-11, after the floodplain maps.

4.5 Delineating Flood Boundaries

The calculated flood depths for the various stream reaches were first plotted on the quadrangle
maps at the cross-section locations. The resulting floodplain widths were compared to the
floodplain widths on the cross-section plots. The floodplain boundaries between the cross-
sections were then approximated by delineating flood depth contours and interpreting the
relationship between those flood depth contours and the ground contours. Consideration was
given to the slope within each reach. The finalized information was displayed on the USGS 7.5'
quadrangle maps (scale of 1" = 2,000'). A table identifying the quadrangle maps used in each
plate and the map scale is given in Figure 8. A map showing the location of each floodplain
map plate is shown in Figure 9, and the floodplain maps are shown in Plates 1-7.

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