FLOOD01452

• County: Larimer
• Community: Fort Collins
• Stream Name: Fossil Creek Drainageway Basin
• Title: Master Drainageway Planning Study
• Date: 8/1/1982
• Prepared For: Larimer County
• Prepared By: Simons Li & Associates Inc.
• Floodplain - Doc Type: Floodplain Report/Masterplan

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LIST OF FIGURES (continued)

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Page

Figure 22.

Flood hydrographs, Lang Gulch at confluence with Fossil
Creek, Developed conditions . . . . . .

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Figure 23.

Flood hydrographs, Smith Creek at confluence with Lang
Gulch, Existing conditions . . . . . . . . . . . . . .

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Figure 24. Flood hydrographs, Smith Creek at confluence with Lang
Gulch, Developed conditions ............... 25

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Figure 25. Flood hydrographs, Burns Tributary at confluence with
Fossil Creek, Existing conditions .. . . . . . . . . . .. 26

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Figure 26. Flood hydrographs, Burns Tributary at confluence with
Fossil Creek, Developed conditions

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Figure 27. Streambank stability study

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Figure 28. Damage frequency curve

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Figure 29. Damage frequency curve

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Figure 30. Schematic of proposed improvements, Alternative 2

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Figure 31. Schematic of proposed improvements, Alternative 3

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Figure 32. Schematic of proposed improvements, Alternative 4

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Figure 33. Damage discharge curves, Fossil Creek Reaches 1 and 2

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Figure 34. Damage discharge curves, Fossil Creek Reaches 4 and 5

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Table 1.

Table 2.

Table 3.

Table 4.

Table 5.

Table 6.

Table 7.

Table 8.

Table 9.

Table 10.

LIST OF TABLES

Percent of One-Hour Rainfall Depth for Five-Minute
Intervals . . . . . . . . . . . . . . .

Rainfall Depths in Inches for 60-Minute Duration, Fort
Collins Area . .

Fossil Creek Rainfall Intensities

Percent Impervious for Developed Conditions

Infiltration Rates for Fossil Creek Basin

Drainage Basin Parameters for SWMM

Fossil Creek Basin, Discharge in cfs for Existing
Conditions . . . . . . . . . . . . . . . . . . .

Fossil Creek Basin, Discharge in cfs for Developed
Conditions ... . . . . .

Existing Bridge and Culvert Data

Existing Conditions Flood Elevation Data, Fossil Creek

Table 11. Developed Conditions Flood Elevation Data, Fossil Creek

Table 12. Existing Conditions Flood Elevation Data, Stanton Creek

Table 13. Developed Conditions Flood Elevation Data, Stanton Creek

Table 14. Existing Conditions Flood Elevation Data, Lang Gulch

Table 15. Developed Conditions Flood Elevation Data, Lang Gulch

Table 16. Existing Conditions Flood Elevation Data, Smith Creek

Table 17. Developed Conditions Flood Elevation Data, Smith Creek

Table 18. Existing Conditions Flood Elevation Data, Burns Tributary

Table 19. Developed Conditions Flood Elevation Data, Burns Tributary

Table 20. Sediment Yield Classification

Table 21. Stream Bank Inventory. . . . . . . . . . . . . . . . .

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Table 22. Aggradation-Degradation Potentials for Fossil Creek and
Tributaries, Existing Conditions ... . . . . . . 47