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Subject: Bed load

As Discharge increases, does bed load increase?

   Suspended loads increase dramatically with discharge, so I would expect that the bed load would increase as well. Bed loads are difficult to observe and measure though, so we have few data on the subject. Measurements on the Niobrara River near Cody, Nebraska, however, have shown that at discharges between 6 and 30 cubic metres per second, the bed load averaged about 50% of the total load. One variable affecting discharge rate is of course velocity, and as velocity increases, so does the stream’s capacity to erode and move the larger particle that make up the bed load.

Dr. Craig Glenn, Professor
Department of Geology and Geophysics
University of Hawaii, Honolulu, HI 96822


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