FLOOD10704 ‎(2)‎

• County: Delta
• Community: Delta
• Title: FIS - Delta
• Date: 8/19/1991
• Prepared For: Delta
• Prepared By: FEMA
• Floodplain - Doc Type: Current FEMA Regulatory Floodplain Information

northeastern Utah. On September 1, 1881, the old Ute Indian
reservation was opened for resettlement (Reference 1).

Mining, lumber, and agriculture comprise the economic base for
Delta County.

The reported Delta County population of 1980 was 21,225, an
increase of approximately 39 percent over the 1970 population of
15,286 (Reference 2). The City of Delta has a population of
approximately 3,931 according to the 1980 census.

The Gunnison River orlglnates at Altmont, Colorado, at the
confluence of the Taylor and East Rivers in Gunnison County, east
of Delta County. From its origin at Altmont, the river flows
approximately 144 miles to its confluence with the Colorado River
at Grand Junction, Colorado, in Mesa County, northwest of Delta
County. The average elevation is approximately 7,700 feet at
Altmont, and 4,550 feet at Grand Junction. This gives the Gunnison
River an average slope of 0.4 percent.

The Uncompahgre River has its headwaters high in the northern
slopes of the San Juan Mountains. It flows approximately 62 miles
on a north-northwesterly course from its origin to its confluence
with the Gunnison River at Delta. Elevation differences in the
drainage basin range from 13,000 feet in the headwater areas to
approximately 4,900 feet at the mouth. The average slope of the
basin is approximately 2.5 percent.

The topography of the City of Delta and Delta County consists
mainly of moderately sloping valleys and mesas, which are highly
dissected by drainageways with steeply sloping sides.

The soils in the City of Delta and Delta County and headwater
regions of the study streams are classified as follows
(Reference 3):

Soil Group

Runoff Potential

Desert-Sierozem
Brown-Chestnut
Mountain Prairie-Chestnut
Gray Wooded-Brown Podzolic-Mountain Prairie

Under Low
Low
Over Low
Under High

Vegetation in the City of Delta and Delta County varies according
to elevation. In the valley areas below 8,000 feet not used for
agriculture, vegetation is classified as northern desert shrub;
that is, sagebrush, western wheatgrass, and winterfat, with an
understory of various hardy grasses. Due to the poor ground cover
in this region, snow tends to melt and run off rapidly.

At the higher elevations, from approximately 8,000 feet to
timberline, sub-alpine forests consisting of aspe~, lodgepole pine,
Douglas fir, and Engleman spruce are common. Runoff in this region

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