FLOOD03155

• County: Bent
• Community: Las Animas
• Stream Name: Arkansas River
• Basin: Arkansas
• Title: Flood Hazard Study
• Date: 5/1/1975
• Prepared For: Las Animas
• Prepared By: Hydro Engineering
• Floodplain - Doc Type: Floodplain Report/Masterplan

storage, including flood control. John Martin Dam was built by
the Corps of Engineers in 1942 to provide flood control for the
Arkansas River valley below the Purgatoire River. It has a
present capacity of 637,000 acre feet.
One smaller dam, Adobe Creek Reservoir, is located on the
first tributary above Las Animas. It is an irrigation reservoir
with a capacity of 62,000 acre feet which provides flood control
on Adobe Creek.

Flood History

Flooding has long been noted in the Arkansas valley and
there are many reports of flood events by the early settlers.
Prior to 1900 however, there are very few well-documented reports
as to flood elevations, discharge, or inundated areas. Several
of the early events which have been summarized by the Corps of
Engineers and the Geological Survey include 1826, 1864, 1867, and
1884. The first documented flood occurred on May 31, 1894. This
flood caused considerable damage above Pueblo, but much less
damage further downstream. The U.S. Geological Survey reports a
flow of 30,000 cfs at La Junta. At Las Animas, the flow was
probably about 25,000 cfs and was reported to have an elevation
of 4 feet less than the 1921 flood. The flood waters reached the
intersection of First and Bent, an elevation of 3892.6 feet. The
reports did not indicate any damage within the city.
The greatest recorded flood in the Arkansas River valley
above John Martin Dam occurred on June 4, 1921. The flood was
caused by intense rainfall between Pueblo and Canon City. This
storm has subsequently been used by the Corps of Engineers to
determine the standard project flood in the Upper Arkansas basin.
The peak flows were 103,000 cfs at Pueblo, 200,000 cfs at La Junta
and 187,000 cfs at Las Animas. This flood was undoubtedly a very
rare event on the Arkansas River in Colorado.
In Las Animas, the flood reached an elevation
and water inundated the north-central and eastern
the city to the intersection of Sixth and Carson.
destroyed the highway bridge north of the city and

of 3896 feet

portions of
The flood

destroyed

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