FLOOD10387 ‎(2)‎

• County: Statewide
• Stream Name: Yampa River
• Title: Floodplain Information Report - Volume 1 - Yampa River from Craig to Dinosaur National Monument
• 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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TABLE OF CONTENTS

Preface
1.0 INTRODUCTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 1

1.1 Purpose . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 1

1.2 Acknowledgements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 1
1.3 Related Flood Studies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 1

2.0 STUDY AREA .............................................. 3

2.1 Location. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 3

2.2 Study Reach ........................................... 3

2.3 Basin Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 5
2.4 Swnmary of Drainage Areas ................................ 5
2.5 Flood Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 7

3.0 HYDROLOGIC ANALYSIS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 10

3.1 Existing Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 10

3.2 New Hydrologic Information ............................... 10
3.3 Equation Selection Process. . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . .. 11
3.4 Hydrologic Findings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 11

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 TillS 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 .
1 Stream Gage Data
2 Drainage Area Swnmary
3 Flow Swnmary
4 Reach Classifications
5 Cross-Section Swnmary
6 Depth of Flooding Swnmary

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