FLOOD08336

• County: Chaffee
• Community: Poncha Springs, Salida
• Stream Name: South Arkansas River
• Basin: Arkansas
• Title: Floodplain Information Report - Lower South Arkansas River
• Date: 4/1/1979
• Prepared For: Chaffee County
• Prepared By: WRC Engineering, Inc.
• Floodplain - Doc Type: Floodplain Report/Masterplan

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away from the stream, on the south side, the soils consist of deep, well-

drained soils on valley side slopes, fans, and terraces used primarily for

irrigated meadows.'

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The vegetation within the study reach consists primarily of cottonwoods,

willows and grasses. The open areas cleared of natural vegetation are used

primarily for irrigated meadows. The general vegetation pattern in the

study area is trees and willows growing adjacent to the stream channel,

followed next by open irrigated meadows, trees growing adjacent to irrigation

ditches traversing along the high meadow areas, and natural grasses growing

on higher terraces and areas further away from the stream channel.

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The historical use of the floodplain has been for range and wildlife

with limited improvements supporting ranching activities, lrrigated pastures

on these plains have good plant cover and support meadow vegetation. Obstruc-

tions of flood flows within the study reach include primarily natural obstruc-

tions such as vegetative growth, fallen trees, and man-made structures including

bridges, buildings, and roadways. These obstructions have the tendency of

increasing the flood elevations upstream of the obstructions and the velocities

downstream of the obstruction. In certain instances, debris accumulating

against a structure can present a potential threat to the safety of the

structure.

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Station 41+00

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Looking upstream.
Note eroding channel
bank at left.

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Photographs of typical stream reaches are included on the following
page s .

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Station 1+50

Looking downstream at
County Road 105 bridge.

Station 45+00

Looking southeast at a
typical pasture adjacent
to the river.

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