FLOOD03253

• County: Boulder
• Community: Boulder
• Stream Name: South Boulder Creek
• Basin: South Platte
• Title: South Boulder Creek Draft Hydrology Study Phase III
• Date: 2/10/2000
• Prepared For: UDFCD
• Prepared By: Taggart Engineering Associates, Inc.
• Floodplain - Doc Type: Floodplain Report/Masterplan

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TABLE OF CONTENTS (Continued)

SECTION VI - REFERENCES

SECTION VII . RAINFALL MEMORANDA AND RESPONSES

SECTION VIII- ELDORADO GAGE AND GROSS RESERVOIR INFORMATION

SECTION IX - SUPPLEMENTAL DEFINITIONS

FIGURES

Figure 11-1 Historical South Boulder Valley Topography. . . . . . . . . . . . . . .. 11-13
Figure 111-1 Below Gross Area Reduction Factors ..................... 111-5
Figure 111-2 South Boulder Creek Rainfall ........................... 111-6
Figure 111-3 100.Year Design Storm ..................,....,...... 111-8
Figure SCS vs. Horton for Infiltration CN = 45 ...................... IV-5
Figure SCS vs. Horton for Infiltration CN = 55 ...................... IV-6
Figure SCS vs. Horton for Infiltration CN = 60 ...................... IV-7
Figure SCS vs. Horton for Infiltration CN = 65 ...................... IV-8
Figure SCS vs. Horton for Infiltration CN = 70 ...................... IV.9
Figure SCS vs, Horton for Infiltration CN = 78 ..................... IV-10
Figure V-1 Gross Reservoir ...........,........................ V-3
Figure V-2 SBC Upstream HWY 93 and Confluence Comparison .......... V-4
Figure V-3 SBC at HWY 93 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. V-5
Figure V-4 SBC - HWY 93 to HWY 36 ............................ V-7
Figure V-5 West Valley Overflow HWY 93 to Flatirons Levee ............ V-8
Figure V-6 West Valley Overflow at HWY 93 ....................... V.9
Figure V-7 Total Stream Flow Arriving at HWY 36 . . . . . . . . . . . . . . . . . .. V-10
Figure V-8 Spill from SBC to West Valley Downstream of HWY 36 ....... V-11
Figure V-9 SBC from HWY 36 to the Wellman Ditch............. ..... V-12
Figure V-1 0 SBe from the Wellman Ditch Downstream ............... V-14
Figure V-11 West Valley Overflow - HWY 36 to Baseline ..,.........,. V-15
Figure V.12 West Valley Overflow on Golf Course . . . . . , . . . . . . . . . . . ., V-16
Figure V,12a Eldorado Gage Data and Comparative SWMM Model.. ...... V-18
Figure V-13 Unit Discharges
Mountains above Gross Upstream Watershed to Element 8 . . . . . . .. V-21
Figure V -14 Unit Discharges
Mountains below Gross to Element 48 . . . . . . . . . . . . . . . . . . . . . .. V-22
Figure V.15 Unit Discharges
Foothills. Element 48 to Element 44 . . . . . . . . . . . . . . . . . . . . . . " V-23

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