PROJ00400

• Contract/PO #: C153588
• Contractor Name: Greeley, City of
• Contract Type: Loan
• Water District: 3
• County: Larimer
• Bill Number: SB 89-85
• Loan Projects - Doc Type: Feasibility Study

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. TABLE OF CONTENTS
Page 2
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. PAGE
1.3 Outlet Works 41
. 1.4 Service Spillway 42
1.5 Auxiliary Spillway 43
1.6 Emergency Spillway 43
. 1.7 Chambers Lake Inlet Channel 45
1.8 Summary of Deficiencies 45
. 2.0 Geotechnical Evaluation 46
2.1 Field Investigation 46
. 2.1.1 General 46
2.1.2 Geologic Mapping 46
2.1.3 Subsurface Investigation 47
I 2.1. 3.1 Dam 47
2.1.3.2 Downstream Dam Foundation 50
. 2.1.3.3 Service and Auxiliary
Spill ways 51
2.1.3.4 Emergency Spi 11 way 52
. 2.2 Laboratory Testing 52
2.3 Seismic Risk Analysis 55
2.4 Slope Stability of Existing Dam 56
. 2.4.1 Procedure 56
2.4.2 Pore Pressures 57
2.4.3 Material Properties 57
I 2.4.4 Fa il ure Surface 59
2.4.5 Results 60
. 2.5 Existing Seepage Conditions 60
2.6 Recommended Interim Operating Restriction 61
. 3.0 Hydrology and Hydraulics 61
3.1 Probable Maximum Flood 61
3.2 Flood Routi ng 63
. 3.3 Outl et Works 64
4.0 Rehabilitation Alternatives 65
. 4.1 Technical Alternatives 65
4.2 Cost Estimates 71
I 4.3 Alternative Selected for Feasibility
Design 72
I 1152c