WSP07449

• File Number: 8056
• Description: Drought Preparedness
• State: CO
• Basin: Statewide
• Date: 7/1/1985
• Author: Resource Consultants
• Title: Droughts and Their Effect on the Water Supplies for the City of Fort Collins Colorado
• Water Supply Pro - Doc Type: Report/Study

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TABLE OF CONTENTS

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EXECUTIVE Sl.Jl1r1ARY................................................... i

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1.

Introduction. . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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Purpose. . . . . . . . . . . . .. . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Organization of report.......................................
Drought definition...........................................
Summary of procedures........................................

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II. Generation of Stochastic Record
and Selection of Typical Droughts..............................

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Calculation of historic annual virgin flows..................
Cross-correlation of virgin flows............................
Basic statistical analysis of annual virgin flows............
Stochastic generation of long-term records......,............
Comparisons to tree-ring results.............................
Determination of drought characteristics.....................
Determination of drought characteristics
for additional drought types.................................
Selection of typical l-in20, l-in-50,
l-in-l00, and l-in-500 droughts..............................
Return frequency of historic droughts,.......................
Generation of annual imports to Poudre River basin...........
Generation of monthly data...................................

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III. Simulation of Poudre River Water Supplies
and Impact of Droughts on City's Water Supply..................

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MODSIM modeL................................................
Yields from C-BT system......................................
System configuration for basin model.........................
Calibration of river basin modeL............................
Results of river basin calibration...........................
Results of drought simulations 6sing basin model.............
System configuration for City network model..................
Operating rules for the City network.........................
Input information to the City network model..................
Operation scenarios..........................................
Yield of individual water supplies...........................
Adequacy of present system...................................
Future supply analysis.......................................

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IV. Water Supply Strategy..........................................

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General. .. . .. . . . . .. . . . . .. . .. . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . 82
Drought design criteria...................................... .82
Future system improvements................................... 83
Need for emergency measures.................................. 84
Emergency measures........................................... 85

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Pa~e

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66
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82