Sediment - Transport Capability in Erodible Channels

The Einstein bed-load function is used as a basis for developing a procedure for evaluating the capacity of an erodible channel to transport material originating from sources outside the bed and having a size distribution different from that of the bed-material load. The method consists of three elements: (1) Bed-material transport rate and descriptive parameters are computed from the Einstein bed-load function; (2) the moving capacity is computed for each size fraction of the assumed conditions of bed roughness and flow; and (3) for assumed inflow-sediment concentrations and size distributions, the rate of scour or deposition is computed by comparing the inflow rate with the combination of moving capacity and bed-material transport rate. Application of the procedure to the Upper Chenab Canal in West Pakistan illustrates the method of computation and use of the procedure to evaluate the need for sediment control in the design of large alluvial channels.