FLOOD04329

• Designation Number: 534
• County: San Miguel
• Community: Unincorporated San Miguel County
• Basin: San Juan/Dolores
• Title: Flood Insurance Study - San Miguel County and Incorporated Areas
• Date: 9/1/1992
• Designation Date: 11/1/2000
• Floodplain - Doc Type: Floodplain Report/Masterplan

census data,
(Reference 3).
follows:

San Miguel County
Census data for

has a population of
the incorporated towns

3,192
are as

Conmunitv

1980 PODulation

Town of Norwood
Town of Ophir
Town of Sawpit
Town of Telluride

478
38
41
1,047

The Town of Telluride, which is located in the southwestern part of
the Colorado Mountain Region, is 13 miles to the east of the Town
of Sawpit.

The San Miguel River watershed near Telluride encompasses
approximately 42.4 square miles and consists of high mountainous
terrain wi th steep to moderately steep slopes. Blevations range
from approximately 8,650 feet to approximately 14,000 feet. The
San Miguel River watershed at Placerville covers approximately 290
square miles. It also consists of high mountainous terrain wi th
steep to moderately steep slopes. The elevation at Placerville is
approximately 7,300 feet. The Leopard Creek watershed, which is a
tributary of the San Miguel River at Placerville, covers
approximately 62 square miles and rises to an elevation of
approximately 9,800 feet. The Fall Creek watershed, which is also
a tributary of the San Miguel Ili ver near the Town of Sawpit,
comprises approximately 42 square miles and rises to an elevation
of approximately 13,300 feet. Leopard Creek and Fall Creek flow
through narrow canyons and their watersheds consist of high
mountainous terrain wi th steep to moderately steep slopes. The
Cornet Creek watershed, which is a tributary of the San Miguel
River, covers approximately 2.4 square miles and rises to an
elevation of approximately 13,300 feet. It consists of high
mountainous terrain with steep to moderately steep slopes.

The annual precipitation in the Telluride area is approximately 27
inches, of which 10 inches occur between May and September. In the
Placerville area the annual precipitation is approximately 16
inches, of which 6 inches occur between Hay and September. The
annual mean temperature in the study area is approximately 40'F,
which varies from 20'F in January to 600F in July. Humidity is
generally quite low, which allows for rapid evaporation (Reference
4). Generally, flooding OCCurs during periods of melting snow in
June; precipitation is generally insufficient to cause floods,
except through cloudbursts.

Soils of the San Miguel River watershed upstream of Telluride are
of the Cryoboralfs-Cryoborulls-Rock Outcrop Associations, which are
classified by the SCS as Hydrologic Soil Group C (soils having slow
infiltration rates when thoroughly wetted), consisting chiefly of
soils with a layer that impedes downward movement of water, or
soils with mod~rately fine to fine texture. These soil have a slow

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