Water Quality Prediction in Mixing Zones of Rivers

Abstract

Steady state models based on the stream tube concept are presented to predict far‐field concentration distributions of pollutants in mixing zones of rivers. Analytical solutions for pipe and diffuser outfall sources, presented by Yotsukura and Cobb (30), are modified to account for the reach‐dependency of pollutant decay rate, transverse diffusion factor and channel hydraulic parameters. The models are validated using field data for a conservative tracer (chloride ion) and a nonconservative pollutant (total residual chlorine) collected in shallow rivers located in Southern Ontario, Canada. In general, the models presented in this paper are applicable to conservative and exponentially decaying pollutants.