FLOOD04613

• Designation Number: 133
• County: Chaffee
• Community: Buena Vista
• Stream Name: Cottonwood Creek
• Basin: Arkansas
• Title: Flood Hazard Analysis - Cottonwood Creek in the Vicinity of Buena Vista, Chaffee County, CO
• Date: 7/1/1978
• Designation Date: 3/1/1979
• Floodplain - Doc Type: Floodplain Report/Masterplan

In the 1974 legislative session, the Colorado General Assembly directly

Located in the west central part of Chaffee County, Cottonwood Creek

drains about 105 square miles. Cottonwood Creek flows in a general

attacked the flood-plain problem by describing it as a natural hazard of

Colorado Revised Statutes 1973, authorizes the Colorado Water Conservation

eastward direction and is fed by three drainages: North Cottonwood,

Middle Cottonwood, and South Cottonwood Creeks. North Cottonwood drains

26 square miles and enters the flood plain study area approximately 1.7

miles east of the upper study limit. The combined drainage area of

Middle and South Cottonwood Creeks is about 65 square miles, They join

to form Cottonwood Creek about 2.9 miles west of the-North Cottonwood

State interest relating to the use of land in House Bill 1041 (Title 24,

Articles 65.1, 32 and 65 CRS 1973, as amended). Section 37-60-l06(1)(c),

Board to designate and approve storm flood-water runoff channels and to

make such designations available to legislative bodies of local juris-

dictions. The Board is providing assistance to local governments in

the development and adoption of effective flood plain ordinances. In

Creek confluence. About 14 square miles of intervening drainages makes

up the balance of the 105 square miles above the confluence with the

addition, the Board assists and provides financial assistance to flood

plain information studies in Colorado.

Arkansas River. The confluence of Cottonwood Creek with the Arkansas

Requests by Chaffee County and the town of Buena Vista to conduct flood

River lies in a narrow entrenched canyon at the lower study limit.

Effects of potential flooding on the- Arkansas River are not included in

hazard -studies are in accordance with State Legislature House Bill 1041

this study. A map showing the location of the study area follows page

which requires local governments to identify and designate areas, such

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as flood plains, that are of state interest.

DESCRIPTION OF THE STUDY AREA

The upstream drainage area originates in the Sawatch Range of the Rocky

Mountains at the top of the Continental Divide between the Arkansas and

The area of study includes the Cottonwood Creek flood plains in the
I
vicinity of the town of Buena Vista. The study area is located within

Gunnison River Basins, Elevations vary from more than 13,000 feet along

the divide to 7,900 feet (mean sea level elevations) at the lower end of

Hydrologic Unit Code Number 11020001. The study begins at the confluence

the study area. Geology in the upper reaches consists of metamorphic

rock (crystalline), mostly granite and other igneous type rocks. Soils

are deep to moderately deep with rock outcrops; and the permeability

of Cottonwood Creek with the Arkansas River and extends upstream through

Buena Vista approximately six miles to the San Isabel National Forest

characteristics are moderate to moderately rapid. Ground cover consists

of native grass, brush, and forestland. Cottonwood, pinon-juniper, and

Boundary. The Arkansas River is a major tributary to the Arkansas-

White-Red Water Resources Council Region,

pine trees grow at the lower elevations. Topography has a significant

effect on the semi-arid climate.

Average annual precipitation varies

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