PROJ00137

• Contract/PO #: C153467
• Contractor Name: Greeley, City of
• Contract Type: Loan
• Water District: 0
• County: Weld
• Bill Number: XB 99-999
• Loan Projects - Doc Type: Feasibility Study

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TABLE OF CONTENTS

Twin Lakes Dam & Reservoir
Page 3.

PAGE

3.0 Hydrology and Hydraul ics 56
3.1 Probable Maximum Flood 56
3.2 Flood Routing 57
3.3 Outlet Works 60
3.4 Dam Breach Analysis 61
4.0 Rehabilitation Alternatives 62
4.1 Technical Alternatives 62
4.2 Cost Estimates 68
4.3 Alternative Selected for Feasibility 68
Design
4.4 Alternatives for Transfer of Twin Lakes 69
Reservoir
4.4.1 Enl argi ng Peterson Dam and 69
Reservoir

4.4.2 Enlarging Comanche Dam and
Reservoir
5.0 Feasibility Design 70
5.1 Design Criteria 70
5.1.1 Foundation Design Criteria 70
5.1 .2 RCC Oam Stabi 1 i ty Cri teri a 71
5.1.3 RCC Dam Desi gn Assumpti ons 71
5.1.4 Earth Dike Embankment Stability 72
Cri teri a

70

5.1.5 Earth Dike Embankment & Foundation 72
Filter and Drainage Criteria
5.1.6 Outlet Works Design Criteria 73
5.1. 7 Spillway Design Criteria 73
5.2 Design Descriptions 74
5.2.1 RCC Dam Foundation 74
5.2.2 RCC Dam 77
5.2.3 Earth Dike Foundation 77