FLOOD00385

• County: Boulder
• Community: Boulder
• Stream Name: Boulder Creek
• Title: South Boulder Creek Interim Hydrology Study
• Date: 7/1/2000
• Prepared For: Boulder County
• Prepared By: Taggart Engineering Associates, Inc.
• Floodplain - Doc Type: Floodplain Report/Masterplan

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TABLE OF CONTENTS (Continued)

SECTION V - HYDROLOGY MODEL ............,.................. V-I

Model Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. V-'I

Limitations ............................................... V-,)
Stream Flow Modeling ....................................... V-;2
Representative 100-Year Flood Hydrographs .............. . . . . . . . . " V-3
Reasonableness Checks ..................................... V-15
Agency and Consultant Reviews ............................... V-2!l

Conclusions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. V-31

SECTION VI - REFERENCES

SECTION VII - RAINFALL MEMORANDA AND RESPONSES, DRAFT REPORT
REVIEW

SECTION VIII - ELDORADO GAGE AND GROSS RESERVOIR INFORMATION

SECTION IX - SUPPLEMENTAL DEFINITIONS

FIGURES

Figure 1-1 South Boulder Creek Discharge Profile ..................... 1-15,
Figure 1-2 The West Valley Overflow Discharge Profile ................. 1-16
Figure 11-1 Historical South Boulder Valley Topography. . . . . . . . . . . . . . .. 11-14
Figure 111-1 Area Reduction Factor Below Gross ...................... 111.6
Figure 111-2 South Boulder Creek 100-Year Rainfall:
Zone 1 NOAA Uncorrected vs. TEA Corrected .............. 111-7
Figure 111-3 100-Year Design Storm: Zone 1 . . . . . . . . . . . . . . . . . . . . . . . . . 111-8
Figure IV-1 SCS vs. Horton Infiltration:
Zone1, 100 Year, Cumulative, CN = 45 .................. IV-5
Figure IV-2 SCS vs. Horton Infiltration:
Zone = 1,100Year, Cumulative, CN = 55................ IV-6
Figure IV-3 SCS VS. Horton Infiltration:
Zone 1,100 Year, Cumulative, CN = 60 . . . . . . . . . . . . . . . . . . IV-7
Figure IV-4 SCS vs. Horton Infiltration:
Zone1, 100 Year, Cumulative, CN = 65 .................. IV-8
Figure IV-5 SCS vs. Horton Infiltration
Zone 1, 100 Year, Cumulative, CN = 70 . . . . . . . . . . . . . . . . . . IV-9
Figure IV-6 SCS vs. Horton Infiltration
Zone = 1,100 Year, Cumulative, CN = 78 . . . . . . . . . . . . . . . IV-10