Solving open channel flow problems with a simple lateral distribution model

A simple lateral distribution model is shown to be a useful tool for analyzing a range of practical problems in river engineering. The model is based on the Shiono & Knight method (SKM) of analysis that takes into account certain 3-D flow features that are often present in many types of watercourse during either inbank or overbank flow conditions. The paper demonstrates the use of this model to predict lateral distributions of depth-averaged velocity and boundary shear stress, stage-discharge relationships, as well as indicating how to deal with some vegetation, sediment and ecological issues. The paper illustrates the use of the SKM approach, and the recently developed Conveyance Estimation System (CES), which is largely based on the SKM, through a number of case studies. The CES features in the Conveyance and Afflux Estimation System (CES-AES) software, which is freely available at www. river-conveyance. net. The paper concludes with a discussion on the limitations and the future potential of the methodology, including the possibility of analyzing steady flows in non-prismatic channels and determining kinematic wave speed versus discharge relationships in unsteady flow.