ADModel is a detailed advection-dispersion mathematical model for the transport of nutrient species along rivers. The model has been calibrated and verified for a stretch of 54km of River Swale, UK, located between Catterick (National Grid Reference, NGR, SE225994508) and Crakehill (NGR SE426734). ADModel presented here is capable to simulate 2 species of phosphorus at high spatio-temporal resolution. The model accounts on field data (water flow and concentrations) and a detailed representation of phenomena which empowers good prediction efficiency of concentrations. ADModel also enables a detailed perspective on the modelling of pollutant transformations in the river stretch. Five classes of transformations are presented for the soluble reactive phosphorus (SRP) and organic phosphorus (OP). ADModel enabled generate empirical relations to express the dynamics of the following process rates: mineralization, sedimentation, resuspension, uptake and adsorption /desorption. These relations cater for a wide range of conditions with respect to water flow, temperatures and seasonality, for which the calibration and verification has been done.