FLOOD10332

• County: Bent
• County: Prowers
• Stream Name: Arkansas River
• Basin: Arkansas
• Title: Arkansas River from John Martin Dam to the Colorado/Kansas State Line: Channel Capacity and Riparian Habitat Planning Study
• Date: 7/1/1999
• Prepared For: CWCB
• Prepared By: USACE
• Floodplain - Doc Type: Floodplain Report/Masterplan

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ARKANSAS RIVER FROM JOHN MARTIN DAM TO
THE COLORADO-KANSAS STATE LINE:
CHANNEL CAPACITY AND RIPARIAN HABITAT PLANNING STUDY

TABLE OF CONTENTS

Topic

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SUMMARY OF FINDINGS AND RECOMMENDATIONS. . . . . . . . . . . . . . . . . . . " i

1. INTRODUCTION .............................................. . . . . . 1

1.1 STUDY AUTIIORITY ........................................... I

1.2 STUDY PURPOSE .............................................. 1

1.3 STUDY REACH AND TYPICAL PROBLEM AREAS ................. 1

2. GENERAL BACKGROUND AND SETI1NG . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
2.1 JOHN MARTIN RESERVOIR PROJECT ............................ 2

2.2 CLIMATE............... " . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 10

2.3 PHYSIOLOGY, GEOLOGY, AND SOILS. . . . . . . . . . . . . . . . . . . . . . . . . . .. 10

2.4 WATER QUALITY. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 10

3. HYDROLOGIC AND ECOLOGIC INVESTIGATIONS. . . . . . . . . . . . . . . . . .. 12
3.1 GEOMORPHOLOGICAL ASSESSMENT. . . . . . . . . . . . . . . . . . . . . . . . . . " 12
3.2 HYDRAULICS AND SEDIMENTATION. . . . . . . . . . . . . . . . . . . . . . . . . . .. 12

Historic Hydrology ............................................. 12
Historic Sediment Information .................................... 14
Hydraulic Modeling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 16
Sediment Modeling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 18
Problem Areas - Existing Conditions ................. . . . . . . . . . . . .. 19
Hydraulic and Sediment Summary ................................. 23
Groundwater/SurfaceWaterInteraction ......................... .... 24
3.3 ECOLOGICAL RESOURCES....... . . . .... . .......... " . ... . " . ... 25

Aquatic System ................................................ 26

Riparian System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 26

Functions of Riparian Vegetation .................................. 28

Riparian Fauna. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 30

4. ALTERNATIVES.......... .... . ....... ...................... .. . .... 31

4.1 CHANNEL IMPROVEMENT. . . . . .. . . . .. .. . . . .. .. .. . . . . .. . . . . . . ... 31
4.2 LIMITED CHANNEL IMPROVEMENT ...................... . .. .... 36
4.3 FLOODW A Y IMPROVEMENT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 36
Structural Alternative: Berm Rehabilitation ......................... 37
Non-structural Alternative: Conservation and Restoration .............. 39
Local Education, Coordination, and Planning . . . . . . . . . . . . . . . . . . . . . . . .. 40

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