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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expect the difference in the two peak discharges to be greater.
However, since the 8,520 cfs value was based on a single large
basin with a single Ie' the level of accuracy from that
approach was considerably lower than the current analysis.

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:l'ABLE 8.3 -=- SUMMARY OF SM DISCHARGES BY RCI

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DRAINAGE AREA PEAK DISCHARGE(l) (cfs)
l.OCATION ( square miles) 10 YR 50 YR 100 YR 500 YR
SM 1 12.78 2,1,20 3,800 4,780 6,800
SM 2 lIi.33 3,610 5,510 6,830 9,1,00
SM 3 15.00 4,230 6,390 7,880 11,000

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(1) These valu,.s result from the 24-hour AMC II storm.

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9.0 SAND CREEK -=- CENTRAL FORK HYDROLOGY

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9.1

Watersh,.d DescriptIon

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The Sand Creek Central Fork (SC) basin is located on the
eastern edge of Colorado Springs as shown in Figure 9.1. The
relativ"ly small basin Is located between Sand Creek Main Stem
and Sand Creek East Fork. ThIs slender basin begIns
approximately at Chicago Rock Island and Pacific Railroad on
the north and drains southward for 1.8 miles through recently
stralgheened and lined ohannel to Platte Avenue. Below Platte
Avenue drainage continues through 1. 6 miles of natural earth
channel with some bank protection to reach the confluence with
Sand Cr"ek East Fork.

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The upper portion of SC is partially developed residential.
The developed central portion of the basin has greater
residential density with some light Industrial use. Land south
of Platte Avenue is the least developed for the basin and
contains a significant amount of open area with natural
vegetat:lon.

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Basin slopes range from an average of 2% in the southern area
to 1,% in the northeast"rn corner. Total drainage area is 1.82
square miles. Soils are a fairly even mix of types "A" and
"B".

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Two previous studies of the basin were available for review.
These were the FIS -=- El Pa~ County (Reference 19) and Sand
Creek Master Draina~ 1'.liJnning Studv -=- City of Colorado Sorings
~ El Paso County ~ Develoom~nt of Alternate Plans developed by
Simons, Li and Associates, Inc. (SIA) in cooperation with Finn
& AssocIates, Ltd. (Reference 17).

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R€~OURC€ CON~UlTI\NT~ INC

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