FLOOD10390

• County: Boulder
• Community: Boulder
• Stream Name: Fourmile Canyon
• Basin: South Platte
• Title: Fourmile Canyon Creek - Major Drainageway Planning - Phase A Report - Alternatives Analysis
• Date: 6/1/2000
• Prepared For: UDFCD, Boulder
• Prepared By: Love & Associates
• Floodplain - Doc Type: Flood Mitigation/Flood Warning/Watershed Restoration

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DAMAGE ANALYSIS
5.1. Introduction
5.2. Methodology
5.3. Descrip~ion of Results

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Major Drainageway Planning
Phase A Report
Fourmile Canyon Creek

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ALTERNATES DEVELOPMENT
6.1. Introduction
6.2. Initial Alternates
6.2.1 Maintain the Existing Floodplain Configuration
6.2.2 A Natural Type Waterway Following the General
Historic Channel Alignment
6.2.3 Selected Structural Improvements and Channel Improvements
6.2.4 Detention and/or Retention Facilities
6.2.5 Acquisition of Flood Prone Properties
6.2.6 Non-Structural Methods
6.2.7 Other-Trans-Basin Diversion of Excess Flood Waters
6.3. Alternate Evaluation

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TABLE OF CONTENTS

EXECUTIVE SUMMARY

INTRODUCTION
1.1. Authorization
1.2. Purpose and Scope
1.3. Mapping and Surveys
1.4. Project History and Correspondence
1.5. Acknowledgments
1.6. Independent Review Panel

LIST OF TABLES
LIST OF FIGURES
LIST OF APPENDICES

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ENVIRONMENTAL ASSESSMENT AND OPPORTUNITIES
7.1. Introduction
7.2. Existing Conditions
7.3. Environmental Goals and Objectives
7.4. Channel Treatment Concepts
7.5. Alternates Evaluation
7.6. Design and Management Recommendations
7.7. References (Chapter 7 only)

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ALTERNATE EVALUATION AND RECOMMENDED PLAN
8.1. Introduction
8.2. Alternate 1 and 2 General Description
8.3.Alternate 1 - 50 Year Channel
8.4. Alternate 2 - 100 Year Channel
8.5. Alternate 3 - Maintain Existing Floodplain Configuration
8.6. Alternate Cost Estimates
8.7. Damage Reduction with Implementation of Alternates
8.8. Cost Benefit Analysis
8.9. Intangible Benefits
8.10. Evaluation Factors
8.11. Recommended Plan
8.12. Additional Considerations and Recommendations
8.13. Future Planning and Design Considerations

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STUDY AREA DESCRIPTION
2.1. General
2.2. Fourmile Canyon Creek Channel
2.3. Topographic Features
2.4. Land Use
2.5. Irrigation Facilities
2.6. Greenways
2.7. Environmental
2.8. Historic Flooding
2.9. Floodplain Regulations
2.10. Previous Studies

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HYDROLOGIC ANALYSIS
3.1. General
3.2. Spill Flows
3.3. Hydrologic Analysis
3.3.1. Original Hydrologic Model
3.3.2.Corrected Hydrologic Model
3.3.3.Future Land Use Hydrologic Predictions
3.3.4.Split Flow Hydrology
3.3.5.500-year Hydrology
3.4. Results of Hydrologic Analysis

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REFERENCES

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HYDRAULIC ANALYSIS
4.1. General
4.2. Base Mapping
4.3. Hydraulic Analysis
4.4. Results of the Hydraulic

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Analysis

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