FLOOD05224

• County: Rio Blanco
• Community: Rio Blanco County
• Stream Name: White River
• Basin: Yampa/White
• Title: Floodplain Information Report
• Date: 4/1/1996
• Prepared For: Rio Blanco County
• Prepared By: CWCB
• Contract/PO #: &&
• Floodplain - Doc Type: Floodplain Report/Masterplan

TABLE OF CONTENTS

Preface
1.0 INTRODUCTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. I
1.1 Purpose. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. I
1.2 Acknowledgements. . . . . . . . . . . . , . . . . . . . . . . . . . . . .. . . .' ._. . . ,. I
1.3 Related Flood Studies ..........,.......................... I

LIST OF FIGURES

2.0 STUDY AREA ...........,.,................................ 3
2.1 Location. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . .. 3
2.2 Study Reach ........................................... 3
2.3 Basin Characteristics . . . . . . . . . . . . . , . , . . . , . . . . . . . . . . . . . . . . .. 5
2,4 Summary of Drainage Areas ................................ 5
2.5 Flood Characteristics . . . . . . . . . . . . . . . . . , . . . . . . . . . . . . . . . . . . .. 7

FIGURE
I Location of Upper Colorado River Basin
2 Location of White Drainage Basin in Colorado
3 White Drainage Basin Map
4 Location of Study Reach With Hydrologic Points
5 Graph of Flow vs. Drainage Area
6 Location of Reaches Within Study Area
7A-F Cross-Sections With Flood Elevations
8 Base Map Topographic Index and Scale
9 Index Map of Plates

3.0

HYDROLOGIC ANALYSIS ....................................

3.1 Existing Data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.2 New Hydrologic Information ...............................
3.3 Equation Selection Process. . . . . . . . . . . . . . . . . . . . . . . , . . . , . . . . .
3.4 Hydrologic Findings . . . .. . . . . . . . . . . . . . . . . . . . . . . , . , . . . . . . .

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PLATE
1-9 Approximate Flooded Area Maps
10-12 Elevation Discharge Curves

4.0 HYDRAULIC ANALYSIS ..................................... 14

4.1 Base Mapping ,........................................ 14
4.2 Stream Reaches ........................................ 14
4.3 Field Surveys and Cross-Section Preparation .................... 17
4.4 Computing Flood Depths. . . . . . . , . . . . . . . . . . . . . . . . . . . . . . . . " 18
4.5 Delineating Flood Boundaries. . , . . . . . . . . . . . . . . . . . . . . . . . . , . .. 19

5.0 INTERPRETATION OF THIS REPORT. . . . . . . . . . . . . . . . . . . . . . . . . . ., 22
5.1 Hydrologic Findings. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 22
5.2 Hydraulic Findings . . . . . . . . . . . . . . . . . , . . . . . . . . . . . . . . . . . . .. 22
5.3 Floodplain Delineations . . . . . . . . . . . , , . , . . . . . . . . . . . . . . . . . . .. 22

6.0 REFERENCES. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 23

LIST OF TABLES

TABLE
I Stream Gage Data
2 Drainage Area Summary
3 Flow Summary
5 Reach Classifications
4 Cross-section Summary
5 Depth of Flooding Summary

PAGE
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IS
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