Current Perspectives on Disinfectant Modelling

Maintenance of a disinfectant residual within water distribution systems is the final barrier in protecting public health. Hydraulic modelling software can simulate the decay of residual but application is limited by reaction and network uncertainties. The state of the art of application of disinfectant modelling is presented here in terms of reaction rate formulations and coefficients, with observations on best practice for operational simulations. Modelling disinfection behaviour assuming idealised bulk reactions, informed by site-specific point of entry tests after any blending and including temperature correction, can provide valuable insight.