FLOOD11770

• County: Douglas
• Community: Douglas County
• Stream Name: Fourmile, Horse, West, Trout Creeks
• Basin: South Platte
• Title: Draft South Platte River Tributaries Hydrology Report
• Date: 5/11/2004
• Prepared For: Douglas County
• Prepared By: Moser and Associates
• Floodplain - Doc Type: Floodplain Report/Masterplan

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DRAFT SOUTH PLATTE RIVER TRIBUTARIES HYDROLOGY REPORT

FOUR MILE CREEK, HORSE CREEK, WEST CREEK, AND TROUT CREEK

TablE~ of Contents

1.0 Intr'oduction .................. ......... ... .............................................................. ........ 2

1.1 Purpose of Study ..................... .................................................................................... ............2
1.2 Authorization and Acknowledgements .............. ....................... .......... ......... ................... ........3

2.0 Hydrologic Analysis ... ..... .............. ....... ... ............... .......... ........... ............... ........ 4

2.1 Rainfall .......... ............... ............ ................ .............. ........ ........... .......... ..... ...............................5

2.2 Sub-Basins.... ........ ....... ............ ........ .... ..... .... ... ......... ...... ...... ... ........ .... .... .......... .............. .......7

2.3 Routing.... ......... ............ ............... ..... ....................... ....... ............................ ....................... ....1 0

3.0 Results ... ....... ................... ....... ...._ ...... ................... .......... .......................... .... 11

4.0 Conclusion ... ........................... ..... ... ...... .... .... ........ ........ .......... ........~..... ....... 20

Refere nces ............................. ...............'......................................... ....... .................... 21

Figures

Figure 1 - Vicinity Map ........ .... ............... ......... ................. .... ............ ........... ........... ................. ....... 3

Figure 2 - HEC-HMS Routing .... ........ ..... ........ ...................... ........... .................. ........ .................... 8
Figure 3 - Four Mile Creek Hydrograph.......................................................................................12
Figure 4 - Horse Creek Hydrograph ............................................ ................................................13
Figure 5 - West-Trout Confluence Hydrograph ...........................................................................14
Figure 6 - West Creek Hydrograph.............................................. ................................................ 15
Figure 7 - Trout Creek Hydrograph .............................................................................................16
Figure 8 - Four Mile Creek Peak Flow Profile .............................................................................17
Figure 9 - Horse-West Creek Peak Flow Profile .........................................................................18
Figure 10 - Trout Creek Peak Flow Hydrograph ........................................................................... 19

Tables
Table 1 - 2-Hour Rainfall Depths and Distribution...........................................................................6
Table 2 - 6-Hour Rainfall Depths and Distribution........................................................................... 7
Table 3 - Sub-Basin Characteristics ........................................................................................... ..... 9

Table 4 - Peak Flow Summary ......................................................................................................11

Appendix A - Rainfall
Appendix B - Sub-Basins
Appendix C - Results

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