FLOOD07093

• County: Otero
• County: Pueblo
• Community: Otero, Pueblo Counties
• Stream Name: Arkansas River
• Basin: Arkansas
• Title: Arkansas River Channel Capacity and Riparian Habitat Planning Study
• Date: 8/1/2001
• Prepared For: CWCB
• Prepared By: US Army Corps of Engineers
• Floodplain - Doc Type: Project

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ARKANSAS RIVER FROM OTEROIPUEBLO COUNTY LINE
TO JOHN MARTIN RESERVOIR
CHANNEL CAPACITY AND RIPARIAN HABITAT PLANNING STUDY

S. RECOMMENDATIONS

The study recommendations are as follows:

· Channel Problem Area No. I - construct and maintain a compound channel extending
from about 2 miles upstream to about I mile downstream of the State Highway 109
bridge at La Junta to allow the free flow of flood flows and to assist with ground water
problems. Maintaining the channel to keep it free of phreatophytes is imperative.

· Channel Problem Area No.2 - construct and maintain a compound channel to facilitate
water and sediment transport; protect the river bank and levee at the old meander near the
threatened portion of the Las Animas Levee, add additional streambank revetment in the
form of larger rip-rap rock or bendway weirs as necessary.

· Channel Problem Area No.3 - construct and maintain a compound channel extending
from a point about 3/4 miles upstream of the U.S. Highway 50 bridge at Las Animas to
the John Martin Reservoir to facilitate sediment transport into the reservoir. Maintaining
the channel to keep it free of phreatophytes is imperative. .

Additional recommendations:

· Conduct a major (Watershed or Environmental Restoration) study of the problems in the
Arkansas River Valley from Pueblo, Colorado, downstream to the Colorado-Kansas state
line. The stakeholders, including all appropriate Federal and State agencies and other
concerned entities such as the U. S. Fish and Wildlife Service, U.S. Geological Society,
Natural Resources Conservation Service, U.S. Department of Agriculture Forest Service,
National Park Service, Colorado Department of Wildlife, Colorado Environmental
Department; and Pueblo, Otero, Bent, Las Animas, and Crowley Counties, as well as
Kansas authorities, should be involved in coordination, consultation, and all key decision-
making. The study should include an extensive vegetation study that would establish a
new and larger set of vegetation survey locations at key problem areas and include re-
survey of all previous vegetation survey sites to provide current quantitative data for
comparison and analysis with those previous vegetative studies.

· Conduct a General Investigations reconnaissance study to identify opportunities to
address flooding/sedimentation problems in the la Junta and Las Animas reaches where
sedimentation has reduced channel capacity and affected levee design performance. It is
recognized that sediment impacts from Fountain Creek and the operation of John Martin
Dam have direct influence on the sedimentation regime.

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