FLOOD10384 ‎(2)‎

• County: Statewide
• Title: Natural Resources of Colorado
• Date: 1/1/1963
• Prepared By: US Department of the Interior
• Floodplain - Doc Type: Educational/Technical/Reference Information

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u.s. Army Corps
of Engineers
Programs

Although it is a regularly constituted branch
of the United States Army, with extensive mili-
tary engineering and construction responsibil-
ities, the Corps of Engineers also is actively
engaged in planning and building projects for
flood control and water conservation, one of its
primary civil functions under Federal law.
In its civil works, the Corps of Engineers
functions on a river basin basis, whenever pos-
sible integrating into a comprehensive plan such
features as flood control, hydroelectric power,
navigation, irrigation, water supply, stream
pollution abatement, recreation, and other
related water uses.
Floods on Colorado's rivers are caused by sus-
tained, high-volume snowmelt; by heavy rains
of cloudburst intensity; or by combinations of
the two.
At the same time, water is a scarce and coveted
resource in considerable portions of the State
where irrigation is the key to successful crop
production. The growth of population and
industry inevitably brings ever-increasing de-
mands for water conservation.

john Martin Reservoir Project
The first improvement for water resources
development built by the Corps of Engineers
in the State of Colorado is the John Martin
Reservoir project, which also has the distinc-
tion of ranking largest in the State with regard
to storage capacity. The dam spans the
Arkansas River about 58 miles upstream from
the Colorado-Kansas State line. The reservoir
extending over 14 miles up the valley and cover:
ing almost 18,400 acres at maximum pool level,

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52

stores and regulates the floodwaters from a
mountainous and rolling-hills drainage area of
18,915 square miles. Recreational facilities
that attract visitOrs from all directions, includ-
ing the neighboring State of Kansas, are centered
around Lake Hasty, a small permanent lake
which has formed from the accumulation of
ground water in a borrow pit just downstream
from the dam.
Congress, realizing the urgent need for both
the control of costly floods and the conservation
of water for irrigation of the fertile Arkansas
River Valley, authorized construction of the
Caddoa Reservoir project in the Flood Control
Act of 1936. The name was changed to the
John Martin Reservoir project by the War De-
partment Civil Appropriation Act of June 1940,
in honor of the late Congressman John A. Martin
of Colorado.
Work on the dam was begun in the fall of
1939; however, operations were suspended from
1943 to 1946 during the war because of critical
material and later shortages, and the project
was not actually completed until October 1948.
Total reservoir storage capacity at maximum
pool elevation (3,870 feet above mean sea level)
is 645,500 acre-feet, based on estimated sedi-
ment depletion since the latest survey in 1957.
About 278,500 acre-feet of this capacity is re-
served for flood control, and the remaining
367,000 acre-feet is utilized for irrigation water
supply storage.
The effectiveness of the John Martin Reservoir
project for both flood control and conservation
has been demonstrated many times. Since it
was placed in operation, eight floods have
originated on the watershed above the dam.
Recent and therefore vivid in the minds of
Arkansas Valley residents was the disastrous
flood of May 1955 which inundated over 30,000
acres of urban and farm lands along the main
stem downstream from Pueblo before its ram-
paging waters were halted by the John Martin
Dam. Major flooding also occurred in the
tributary Purgatoire River Valley in addition
to minor flooding from the other tributaries
in that area. The near-record floods caused
damages of more than $4 million-a figure
which would have been more than doubled
had the dam not been in place to catch the