channel classification

The categorization of river channels. Descriptive classifications are generally based on the degrees of sinuosity and braiding, and the type of sediment load (suspended, mixed, or bedload), since this controls the relative stability of a channel which, in turn, affects channel pattern. The most basic categories are: straight, meandering, and braided.

Quantitative classifications attempt statistically to relate different morphological properties of a channel to possible causal factors; for example, bankfull discharge and channel slope. Thus, L. B. Leopold and M. G. Wolman (1957) were able to distinguish graphically between braiding and meandering states, based on bankfull discharge (Q_b) and channel slope (s): S = 0.013 Q^-0.44_b. However, there are many controls on channel morphology, and simple models are rarely applicable.

The classification of a river channel pattern is difficult; for example, a channel braided at low flows may look straight at high flows, and it may be that there is a continuum of forms and processes, rather than discrete categories.