Authors: Luna B. Leopold and William W. Emmett. Abstract: A bedload trap in the riverbed provided direct quantitative measurement of debris-transport rate in the East Fork River, Wyoming, a basin of 466 km( drainage area. Traction load moves only during the spring snow melt season. Data collected in three spring runoff seasons showed that transport rate is correlated with power expenditure of the flowing water and at high flows becomes directly proportional to power as suggested by Bagnold. Originally published: Proceedings of the National Academy of Sciences ; v. 73, no. 4 (April 1976).