Optimization of Waste Removal for Wide Shallow Rivers

A two-dimensional water quality management model is presented for rivers where quality constraints are stated for only a portion of the channel cross section defined as a clearlane. The model is applicable for discharges into rivers when dilution by lateral mixing or degradation, or both, by aerobic decay results in allowable concentrations over a portion of the channel. Results are presented for an example involving five outfall discharges along a river with four different configurations of the physical situation comprising different channel shapes and mixing assumptions. Water quality management strategies, including the optimal waste treatment cost, are shown to be dependent on the physical nature of the receiving river and the definition of the clearlane.