7050

• UCREFRP Catalog Number: 7050
• Author: Andrews, E. D.
• Title: Effective And Bankfull Discharges of Streams In THe Yampa River Basin, Colorado and Wyoming
• USFW Year: 1980
• USFW - Doc Type: Journal of Hydrology
• Copyright Material: YES

322

Factors influencing the duration of the effective discharge

The conceptual mo~l of geomorphic forces presented by Wolman and Mil-
ler (1960) (Fig. 1) indicates that the duration of the effective discharge should
depend upon the distribution of streamflows and the threshold of sediment
movement. As described previously, the duration of the effective discharge
will become shorter as the relative proportion of large flows increases, or as
the threshold of sediment movement increases, or both. Conversely, the dura-
tion of the effective discharge will become longer as the relative proportion
of large flows decreases, or as the threshold of sediment movement decreases,
or both.
The relative significance of large streamflow at a gaging station may be re-
presented by the skew of the distribution of the streamflows. The skew (SK)

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Fig. 7. Relation between drainage area and the skew of daily mean discharge.

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