FLOOD00235

• County: Statewide
• Community: State of Colorado
• Stream Name: All
• Title: Stream, Riparian, and Wetland Ecology - Class material, Volume 1 of 2
• Date: 9/1/1987
• Prepared For: Students
• Prepared By: Professor Windell
• Floodplain - Doc Type: Educational/Technical/Reference Information

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the bends are not reguler and pronounced &II in meande'rir;g teachen.' Even in
straight reaches the current tends to wander from one, streubenk to the
other. As high flows decrease, suspended solids and bed load deposition
occurs forllling bars (i.e., the appearance of small islands at IO~1 flow)
opposite from the main current. These barD alternate along the l~nk. .0
that a meandering flow develops in a straight channel at lowH flo.,-,(Figure
8). When the streambanks contain large rubble and boulders (i.e.,
armored), the'.treaa channel tends to be non-erodible, highly st..ble and
resistant to the meandering proces..

PLA.N VIEW

RIFFLE

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RIFfLE

RIFFLE

PROF'lLE VIE\.'

/-'''IATER SURFACE
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POOL

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POOL
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STREAMSED-- .

Fll1\1r. R. Pool and riffle fof1Ution In a stt'llltht chann~l (upper).
Profile view of humps and depressions fo~ln8 pools and riffles in
the .tre.~bed (lower).

Braided Pattern

A braided stream channel is characterized by mult.iple channels that
endlessly divide and rejoin (Figure 3). The term anas,tomosis which
describes the branching and rejoining of blood vesser; is sometiml!S used to
describe the braiding process. The two basJlc characteristics of braided
streams are that they have easily eroded stlreambanks .nd that they have
more bedload than the stream can transport. As the channel beCOml!S
overloaded with sediment, deposition occurs" At low flow, bars form in the
widened channel and stabilize to form small islands. This procesll tends to
fill the channel and is commonly called .!9udation. In an efforl: to
maintain equilibrium the stream gradient increases, velocity inCrl!aSeS, and
multiple channels again develop. In areas, lacking st.,bUidng streambank
vegetation, the multiple interlaced channels also cause the system to

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