Integral transform solution of a two-dimensional model for contaminant dispersion in rivers and channels with spatially variable coefficients

The Generalized Integral Transform Technique (GITT) is employed to obtain numerical–analytical solutions for mathematical models that predict the dispersion of dissolved pollutants in rivers, streams and channels with either symmetric or asymmetric flow. The two-dimensional steady-state model presented allows for the use of variable coefficients represented by non-uniform velocity profiles and turbulent diffusion coefficients, in any general functional form. The proposed model is then applied to an example of biocides contamination downstream of thermohydroelectric power stations, originated from the cleaning of cooling water systems undergoing biofouling.