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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When compared to tl,e discharge values obtained from the
previous studies, the 100-year peak discharge of 5,570 cfs
occurring at the confluence with Fountain Creek (discharge
point SHR7 in Table 2.3) is clearly in the range between the
two. As the peak discharge of 7,800 cfs from the Frs was
thought to be unreasonably high, it is not unexpected that the
newly generated value be below this leveL Likewise, it is not
surprising that the newly generated value is greater than the
4,524 cfs discharge presented in the SHRMDR. As the latest
analysis is based on storm parameters defining a more severe
rainfall event, it should be expected that this would coincide
with a higher magnitude of runoff as shown by the results.

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IABl.E 2.3 -=- SUMMARY OF SHR DISCHARGES BY RCI

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DRAINAGE AREA PEAK DISCHARGE(l)(cfs)
LOCATION ( square miles~ 10 YR 50 YR 100 YR 500 YR
SHR 1 1. 98 280 500 670 NA(3)
SHR 2 1. 98 0 0 0 NA(3)
SHR 3 2.88(2) 340 630 1,100 1,800
SHR 4 I.. 78 (2) 1,160 1,910 2,510 3,700
SHR 5 6.71, (2) 2,350 3,740 4,870 7,000
SHR 6 7.37(2) 2,630 4,180 5,480 7,600
SlIR 7 7.82(2) 2,640 4,230 5,570 8,000

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(1) These vahws result from the 24-hour AMC II storm.
(2) These valuE!s do not include the upper basin area.
(3) The 500-year discharge was not determined for points outside the
study reach.

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3.0 CHEYENNE RUN !lXDROl.OGY

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3.1

WatershE!d Description

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Cheyenne Run Basin (CR) Is located in western Colorado Springs
up against the Foothills below Cheyenne Mountain and contains
the communi ties of Ivywild and lower Skyway Park. As observed
in FIgure 3.1, It Is the northern tributary to Cheyenne Creek
with the confluence for the two located near the intersection
of Tejon Street and Navajo Street. General flow in the
drainage is from west to east. The watershed originates on
steep hillsides at its western boundary with elevations
reaching the 7,400 feet level and slopes of as much as 40%.
Elevations in the eastern portion drop down to 5,920 feet,
with average slopes of 2 to 4%.

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Total area of the watershed is 1.54 square miles. At present,
the steep western portion of the basin is primarily
undeveloped. Development tends to increase moving eastward,
with the eastern most subbasin fully developed. Primary land
use within the watershed is for various densities of
residential occupation with a few small interspersed commercial

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R€~OURC€ CON~UlTI\NT~ INC

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