Rosgen Class C5 Forest Reference Stream Monitoring Data

In his book Applied River Morphology, Dave Rosgen describes the C5 Stream Type as "a slightly entrenched, meandering, sand-dominated, riffle/pool channel with a well developed floodplain." He goes on to say that:

"The C5 stream type occurs in broad valleys and plains areas with a history of riverine, lacustrine, glacial (outwash and glacio-fluvial), and eolian deposition. The C5 stream type can be found in very low relief basins typical of the interior lowlands, Great Plains, coastal plains, and in river deltas. Glacial outwash areas can also develop C5 stream types.

C5 stream channels have gentle gradients of less then 2%. The C5 stream channel displays a higher width/depth ratio than the C4 and C3 stream types due to the depositional characteristic of the stream bed and the active lateral migration tendencies. The riffle/pool sequence for the C5 stream type averages 5-7 bankfull channel widths in length. Bed forms of ripples, dunes, and anti-dunes are prevalent.

The stream banks are generally composed of sandy material, with stream beds exhibiting little difference in pavement and sub-pavement material composition. Rates of lateral adjustment are influenced by the presence and condition of riparian vegetation. Sediment supply is high to very high, unless stream banks are in a very low erodibility condition.

The C5 stream type, characterized by the presence of point bars and other depositional features, is very susceptible to shifts in both lateral and vertical stability caused by direct channel disturbances and changes in the flow and sediment regimes of the contributing watershed.

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  Click to enlarge Class C5 Stream in Summer 2002
  
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  Click to enlarge Class C5 Stream in Summer 2002
  
• View a video clip of a Class C5 Stream in Summer 2002

Resources Describing C5 Stream Hydraulic Geometry:

• Chart showing dimensionless BKF stage discharge curve - (PDF format; 10KB)
• Chart showing dimensionless hydraulic geometry curves and equations - (PDF format; 39KB)

Last modified: Monday, 10-Mar-2008 15:31:56 EDT