Document Type

Thesis - Open Access

Award Date


Degree Name

Master of Science (MS)


Civil Engineering

First Advisor

Alan L. Prasuhn


In 1973 Ackers and White introduced a method which calculated sediment transport based on an effective or significant particle size. They did not take grading of sediment into account. In 1980 White and Day presumed that because the riverbed materials are non-uniform using a significant size is too simplified. They modified the Ackers-White transport equation so it can be used in transport calculation with graded sediments. In 1984 Jeff Lewandowski, a graduate student at SIEJ, used the data from the White and Day study and modified the original Ackers and White equation so it can be applied to graded sediments as well as uniform sediments. He generated a curve for use in graded sediment transport calculation using the threshold values for transport in a particular set of data done in the flume studies from the White and Day work. The data for this set were not big enough to find out how the curve behaves when larger sizes were used. He wrote a computer program to analyze the data. The goal of this research was to improve the modified method. The specific objectives were as follows: 1) Modify the computer program so it can be used for any set of data given. 2) Generate a new threshold curve, if necessary, using the broadest possible range of sediment sizes. 3) Verify matching of the calculated modified method con­ centration to measured concentration in river data. 4) Test additional data to verify matching the calculated original Ackers-White concentration with calculated modified concentration in both flume and river data. 5) Test additional data to verify matching the calculated modified transport values to actual transport values for each size fraction.

Library of Congress Subject Headings

Sediment transport



Number of Pages



South Dakota State University


No Copyright - United State