FLOOD07134

• County: San Miguel
• Community: San Miguel County
• Stream Name: San Miguel River
• Basin: Gunnison
• Title: Technical Addendum for Flood Insurance Study San Miguel County
• Date: 5/1/1977
• Prepared For: San Miguel County
• Prepared By: Camp Dresser & McKee
• Floodplain - Doc Type: Floodplain Report/Masterplan

FLOOD CHARACTERISTICS

Major flood flows in the study area result from rapid melting of the

mountain snowpack during the period from late May to early .July,

and are characterized by moderate peaks, large volumes and long

duration of flows. Percipitation is q'~::1erally insufficient: t:o

cause floods except cloudbursts. A flood resulting from a cloud-

burst rises so quickly that it. has a peak durat:ion of only a few

minutes, followed by a rapid subsidenc(, 0 Past: recoJ~ds indicate

that most of the severe floods in this region were caused by

cloudburst, especially for small drainage areas.

FLOOD HISTORY

The only severe floods in the San Mi<:Jue1 River Basin for which

defini t:e information is available befon:, 1948 w'erel:hose of

September 5, 1909, and October 5, 1911.

The flood in 1909 caused

the failure of two small power reservoirs of t:he Telluride Power

Company on Lake Fork of the San Mi<:Juel. 'rhe flood in 1911 washed

out railway tracks and public roads, anc: caused the failure of

Trout Lake Dam and loss of one life. Flood also occurred in 1:he~;e

study areas to a lesser extent in 1913, 1923, 1927, 1964 and 1966

in the San Mi<:Juel Basin. Most of the flood problems in the Town

of Telluride are caused by Cornet Creek because the crown oE Telluride

lies on the alluvial fan of Cornet Creek, Flood hazards are due

mainly to mud and debris flows. Flood '3 occurred on :ruly 27, 1914,

and .l\.ugust 1, 1969; these were two of I:lw most destruct:ive mud and

debris flows, and were caused by heavy rainfall preceded by a period

of vle't weather.

It is likely that the flood was caused by l.arge

boulders and debris jamming the narrow channel of Cornet Cn~ek at:

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