WSP05269

• File Number: 8142.400
• Description: Trinidad Project - Reports
• State: CO
• Basin: Arkansas
• Water Division: 2
• Date: 4/1/1964
• Author: US BOR
• Title: US Bureau of Reclamation - Trinidad Irrigation and Flood Control Project - Preliminary Report - Volume I
• Water Supply Pro - Doc Type: Report/Study

O~1821

.

1921, caused by the najor "funnel"of the Cannon City - Pueblo-

Colorado Springs rC-Jgion. The Pueblo type of storm on the Purgatoire

Hiver basin Clbove Trinidnd will be of lesser intensity because of

the differing geogrc,phical characteristics of the two "rear!. Unlike

the terrain between C,mon City and Pueblo, the areo. above Trinidad

is more of the mountain type with very little exposure along the

"front rl:'.nge." Protection here afforded by the higher elevations

and the lhaited nccess by air musses from the plains precludes the

occurrence of storms greatly hI excess of the Pueblo storEI.

The third general clccss is illustmted by the storm that

caused the 190L,. flood on the Purgatoh'e River. General rain for

several days followed by a shorter period of rain of neICeI' cloud-

burst intensity is the general characteristic of [mch storns, which

may be wide in extent. The resulting flood, deriv",d from D. pre-

s".turated watershed, Vlill probnbly create mnx1nwn flood conditions

in thi[i f.lrc;::t.

.

Flood Analysis

The Purgatoire Hiver rises at Iln elevc.tion of 13,000 feet

on the eastern slope of the Sangre de Cristo He.nge, dividine the

Ark0,nsQs nnd Rio Grcmde basins, and drops to 6,000 feet at Triniclnd

with an Ilverc.ge fall of about 1/+0 feet per raile. Slopes in the upper

fourth of the watershed are much greater tlmn this avera'5e, since

the l""'jor pl"rt of the strear1's fall occurs in this reach. The drain-

age area averages about 20 miles in \ddth with "-reas of 642 tend 742

squQre milf,;s above the Sopris Dara site and Triniunu, respectively.

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