FLOOD07093

• County: Otero
• County: Pueblo
• Community: Otero, Pueblo Counties
• Stream Name: Arkansas River
• Basin: Arkansas
• Title: Arkansas River Channel Capacity and Riparian Habitat Planning Study
• Date: 8/1/2001
• Prepared For: CWCB
• Prepared By: US Army Corps of Engineers
• Floodplain - Doc Type: Project

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ARKANSAS RIVER FROM OTERO/PUEBLO COUNTY LINE
TO JOHN MARTIN RESERVOIR
CHANNEL CAPACITY AND RIPARIAN HABITAT PLANNING STUDY

TABLE OF CONTENTS

Topic

Pa~e

SUMMARY OF FINDINGS AND RECOMMENDATIONS.........................................iii

1. INTRODUCTION ........................................................................................................ 1
1.1 STUDY AUTHORITY ........................................................................................ 1
1.2 STUDY PURPOSE .............................................................................................. 1
1.3 STUDY REACH AND TYPICAL PROBLEM AREAS .................................... 1
2. GENERAL BACKGROUN"D AND SETTING ......................................................... 5
2.1 JOHN MARTIN RESERVOIR PROJECT........................................................... 5

2.2 CLIMATE............................................................................................................... 8
2.3 PHYSIOLOGY, GEOLOGY, AND SOILS ........................................................... 9

2.4 WATER RESOURCES .......................................................................................... 9
2.5 THE CHARACTER OF THE ARKANSAS RIVER: A HISTORIC .......................

PERSPECTIVE............................................................................................................ 10
3. HYDROLOGIC AND ECOLOGIC INVESTIGATIONS....................................... 23
3.1 GEOMORPHOLOGICAL ASSESSMENT ......................................................... 23
3.2 HYDRAULICS AND SEDIMENTATION....................................................... 24

3.2.1 Historic Hydrology ......................................................................................... 24
3.2.2 Historic Sediment Information..............................:......................................... 29

3.2.3 Hydraulic Modeling ........................................................................................ 31
3.2.4 Sediment Analysis......... ... ... ... ................................... ..... ................ .... ..... ........ 31
3.2.5 Problem Areas - Existing and Improved Conditions.................................... 35
3.2.6 Hydraulic and Sediment Summary ................................................................. 38

3.3 ECOLOGICAL RESOURCES ............................................................................. 38
3.3.1 Aquatic System ............................................................................................... 39
3.3.2 Riparian System .............................................................................................. 39
3.3.3 Functions of Riparian Vegetation ................................................................... 41
3.3.4 Special Status Species..................................................................................... 42

3.3.5. Riparian Fauna ................................................................................................ 43
3.3.6 Salt Cedar Removal............................................................;........................... 44
4. DOCUMENTATION OF VEGETATION AND CHANNEL PROBLEMS ........... 46
4.1 RESULTS-AERIAL PHOTOGRAPH COMPARISONS OF VEGETATION

........................................................................................................................46
4.2 INTERPRETATION OF CHANNEL PROBLEMS AS SEEN IN AERIAL

PHOTOGRAPHS........................................................................................................ 49

5. RECOMMENDA TIONS ............................................................................................. 60

6. REFERENCES CITED ............................................................................................... 62

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