FLOOD07005

• Designation Number: 190
• County: Mesa
• Community: Collbran
• Basin: Colorado Mainstem
• Title: Flood Insurance Study - Collbran, Mesa County, Colorado
• Date: 10/1/1981
• Designation Date: 6/1/1982
• Floodplain - Doc Type: Floodplain Report/Masterplan

in northeastern Utah. On September 1, 1881, the old Ute Indian
reservation was opened for resettlement. Cattle ranchers settled
in the area which is now COllbran, and the town itself was incor-
porated in 1908. The population of the Town of Collbran was 297
in 1976 (Reference 1), an increase of 27 percent since 1970 (Refer-
ence 2) .

Plateau Creek has its headwaters in the Grand Mesa National Forest,
approximately 18 miles southeast of Collbran. The stream flows
northwesterly from its origin near Chalk Mountain into Vega Reservoir,
approximately 11 miles upstream from Collbran. Plateau Creek
then continues westerly from Vega Reservoir through Collbran to
its confluence with Colorado River approximately 19 miles downstream
from Collbran. The area drained by Plateau Creek at the downstream
corporate limits of Collbran is approximately 316 square miles.
The drainage basin of Plateau Creek drops from an elevation of
11,000 feet at its headwaters to 6,000 feet at Collbran.

Grove Creek has its headwaters in the Grand Mesa National Forest
approximately 10 miles southeast of Collbran. The stream flows
northwesterly from its origin near the Sheep Flats through Collbran
to its confluence with Plateau Creek just west of the downstream
corporate limits of Collbran. Grove Creek has a drainage area
of approximately 21.6 square miles at its confluence with Plateau
Creek. The drainage basin drops in elevation from 10,400 feet
at its headwaters to 5,950 feet at its mouth.

The flood plains of Plateau Creek and Grove Creek are residentially
developed. There is also some minor commercial development in
the Plateau Creek flood plain.

Buzzard Creek has its headwaters in the Grand Mesa National Forest
approximately 21 miles southeast of Collbran. Buzzard Creek drops
from an elevation of 10,000 feet at its headwaters to 5,950 feet
at its confluence with Plateau Creek in Collbran.

The topography of the study area consists of gentle to moderately
sloping valleys and mesas, highly dissected by drainageways with
steeply sloping sides.

Soils in the Plateau Creek basin are characterized by three general
zones. Zone One, which includes the upper areas of the Battlement
Mesa and the Grand Mesa, consists of two general major soil groups,
the Gray Wooded and Brown Podzolic Zonal great soil groups. The
soils are rapidly permeable to very rapidly permeable. Winter
snowfall is heavy in this area, but runoff is slow because of
the pervious soil and good to excellent ground cover conditions.
The dominant vegetative cover consists of pine, spruce, alpine
fir, and aspen trees. Zone Two, which includes the lower areas
of the Battlement Mesa and the Grand Mesa, consists of two general
major soil groups,the Mountain Chernozem and Chestnut Zonal great

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