PERMFILE120564

• Permit No: C1981020A
• IBM Index Class Name: Permit File
• Doc Date: 11/4/2002
• Section_Exhibit Name: Appendix M‎(i)‎ to M‎(viii)‎
• Media Type: D
• Archive: Yes

• ESTIMATE OF FLOOD CHARACTERISTICS FOR EAST SALT CREEK
BELOW CONFLUENCE OF
EAST SALT AND MUNGER CREEKS, GARFIELD COUNTY, COLORADO
Procedure for ungaged sites with streams in mixed population
flood areas:
1 - Compute basin and llimatic parameters:
Mountain Region Southern Plateau Region
Drainage area A = 24mi2 (planimetered) A = 87.4mi2 (planimetered)
Mean Annual PPT. P = 21.4mi
2 - Compute flood characteristics for Southern Plateau Region
from Table 4:
•
Peak Discharges of
Selected RI Floods
410 -_ 59.7 (87.4)0.709 = 1421cfs
450 = 89.1 (87.4)0.709 = 2120cfs
4100 = 103 (87.4)0.710 = 2462cfs
4500 = 137 (87.4)0.713 = 3319cfs
47 +56 to -36
STD Error of Estimate, $
Average Range
50 +62 to -38
53 +66 to -40
65 +84 to -46
If study site is above 6500 ft. reduce flood discharges according
to Figure 11:
E. S. C. Sub-basin below M. C. 6500' - 7500' (excludes mountain region)
A = 56.6mi2 (planimetered) Average Elevation = 7000 ft; Flood Reduction
Factor = 0.5.
410 - 59.7 (56.6)0'709 = 1044cfs x 0.5 = 522cfs
450 = 89.1 (56.6)0.709 = 1558cfs x 0.5 = 779cfs
•