ABSTRACT
Understanding the principles of sediment transport by flowing water is essential to interpreting and solving many problems. The individual characteristics of water and sediment and their interaction directly affect the type and volume of material eroded and transported and the place and time of deposition. Evaluating channel instability, including erosion or aggradation, and predicting the performance of proposed channel improvements are problems that require knowledge of sediment transport and the use of procedures pertaining to it. Information derived from applying sediment transport prediction procedures can be used to determine the requirements of storage of coarse sediment in debris basins and other types of structures. This chapter includes a discussion of the characteristics of water as a medium for initiating the movement and transport of sediment. The reaction of material on the streambed to the hydraulic forces exerted and the effect of velocity and flow depth on the rate of bed material transport are described. Formulas and procedures designed to predict the rate of bed material transport are given and evaluated. Recommendations are made for applying these formulas and procedures to channel problems. The chapter concludes with a discussion of the mechanics of suspended load transport and a description of a method for computing suspended load yield from concentration and flow duration data.
