FLOOD04641

• County: Denver
• Community: All
• Stream Name: All
• Basin: South Platte
• Title: Proposed Hydrology for use in Hydraulic Analysis of FEMA Flood Studies and Restudies
• Date: 9/1/1989
• Prepared For: State of Colorado
• Prepared By: Resource Consultants
• Floodplain - Doc Type: Educational/Technical/Reference Information

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current DCM criteria. With only few modifications, Rcr adopted
the same hydrologic parsmeters as the KEC study. A summary of
parameters for the 29 subbasins is presented in Table 10.2.

TABLE 10.2 .:. SUMMARY OF SET BASIN PARAMETERS

SUBBASIN

DRAINAGE AREA
(square miles)

CURVE NUMBER
CN

TIME OF
CONCENTRATrON. Ic

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19
21
22
23
33
34
35
37
38
39
40
42
58
59
60
61
62
63
64
65
66
67
68
69
70
87
88
89
90

0.29
0.10
0.13
0.20
0.50
0.23
0.26
0.20
0.12
0.48
0.14
0.20
0.28
0.32
0.08
0.35
0.25
0.06
0.20
0.07
0.11
0.19
0.10
0.23
0.26
0.15
0.26
0.10
0.06

49
62
62
58
59
62
62
74
62
60
46
54
41
55
62
61
47
40
40
40
40
40
40
40
40
42
42
42
40

0.51
0.53
0.07
0.91
1. 37
0.59
0.87
0.78
0.89
0.45
1.11
0.37
0.55
0.44
0.19
0.44
0.19
0.67
0.63
0.52
0.19
0.89
0.22
1.42
0.88
1. 35
0.29
0.46
0.63

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Peak dtscharge results from the 2-hour AMC rII storm are
containE!d in Table 10.3 for the hydrologic discharge points
highlighted on Figure 10.1. The 100-year discharge of 1,970
cfs at the confluence with Sand Creek East Fork closely matches
the 2,026 cfs determined by the KEC study.

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Comparison to the other two previous studies is not as
straightforward as they were conducted under considerably
different assumptions. However. it does seem reasonable that
the peak discharge generated by the SI.A study for developed
conditions should be hIgher than those being presented here for
existin~; condItions on a largely undeveloped basin.

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1.3

R€~OURC€ CON~UlTI\NT~ INC

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