FLOOD00945

• County: Teller
• Community: Cripple Creek
• Stream Name: Pony Gulch, Poverty Gulch
• Title: Floodplain Management Study
• Date: 12/1/1992
• Prepared For: Cripple Creek
• Prepared By: USDA Soil Conservation Service
• Floodplain - Doc Type: Floodplain Report/Masterplan

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DESCRIPTION OF STUOY AREA

Basin Characteristics

study Limits

The watersheds that produce runoff to channels in and around Cripple
Creek are relatively small in size and at high elevation. These two
characteristics are very significant to the area hydrology.
Elevations range from 10500 ft at the upper reaches of the watersheds
to 9300 ft at the southern boundary of the city of Cripple Creek.
Slopes range from 4 percent to 20 percent and greater.
The soils in the basin are alluvium along stream channels (hydrologic
group B), and a mix of skeletal soils (hydrologic C and 0) on the
slopes accompanied by areas of rock outcrop (hydrologic group OJ. The
parent material is generally Trachyte, a light colored igneous rock
consisting essentially of alkalic feldspar with low shrink swell.
There is no detailed soil survey report available for the basin.
The vegetation in the upper watersheds is predominately native range
with some forest and rock outcrop areas. ,A significant part of the
lower basin is occupied by residential and commercial properties.
Past mining activities have left numerous scars in the watersheds
where little vegetation exists.
The flood plains, within the study limits, generally contain typical
residential and commercial property improvements such as buildings,
yards, fences, streets, vehicles, etc. Vegetation such as lawns,
shrubs, trees, flowers, and forbes are a part of the landscape. There
are some willows and cottonwoods along those channels that have a
sustained water supply. The channel does a considerable amount of
meandering whiCh enhances the visual aesthetics and wildlife habitat
values in the area.

The study
limits of
reaches;

includes most of the drainage ways within
the city of Cripple Creek. This includes

tho
tho

corporate
following

Reach

Lenath

Main Street Tributary
Cripple Creek
Poverty Gulch
Second Street Tributary
Courthouse Tributary
Thurlow Avenue ~ributary
Pony Gulch

0.38 Miles
1.06
0.41
0.63
0.35
0.19
1.06

Total

4.26 Miles

An index map showing the location of flood plain mapping is included
as figure 2. The flood plain maps themselves are shown as sheets 1
and 2 following the index map.

The mean annual precipitation for the basin ranges from 16 to 20
inches. The mean annual precipitation in Cripple Creek itself is 16.3
inches with July and August accounting for the greatest monthly
values. Snowfall does occur throughout the winter period however
there is no large accumulation. An analysis into the contribution of
spring snowmelt to flooding suggests it is not a significant factor.
Summer rains are the most likely to produce flooding in the study
area.