FLOOD05134

• County: Jefferson
• Community: Lakewood
• Stream Name: South Lakewood Gulch
• Basin: South Platte
• Title: Flood Hazard Area Delineation
• Date: 7/1/1977
• Prepared For: Lakewood
• Prepared By: UDFCD
• Contract/PO #: &&
• Floodplain - Doc Type: Floodplain Report/Masterplan

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in the case of flow in a triangular channel.

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"The model solves the kinematic wave equations by numerical techniques.
The details of these techniques have carefully been developed over a
period of many years to the point where reliable procedures have been
programmed to automatically assure the most economical solution of these
equations. These numerical procedures discretize time in steps of t. t
and distance in steps of t. x.

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"Over anyone time, i and f are assumed to remain constant. Variables
i and f also are assumed to remain constant over x. Variations with
x of f can be represented in stepwise changes by a cascade of overland
flow segments. Along any stream segment, the variable q changes con-
tinuously with time but is assumed constant over the length of the stream
segment. II

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RUNOFF VOLUMES

In addition to the peak rates of flow presented in Section II I, storm
runoff volumes were determined at each design point for each frequency.
This was done for both present conditions and future development, and
these were found to agree within 5 percent. For this reason, only the
runoff volumes for future development are presented below in Table HA-3.
Volumes shown are cumulative values at the lower end of each subbasin.

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TABLE HA-3

RUNOFF VOLUMES

FUTURE OEVELOPMENT
(A II va lues in ac re- fee t)

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DISCHARGE

{in cu

Subbasin

1
2
3
4
5

5-year 10-year 50-year 100-year
10 18 23 26
30 55 70 78
41 74 95 105
51 92 118 131
63 114 147 163

FIGURE HA-I
WRIGHT- MCLAUGHLIN ENGINEERS
2420 ALCOTT ST. OENVER.COUC.B02~