TESTING THE SANCHO MODEL ON DISTRIBUTION-SYSTEMS

Empirical findings were used to evaluate a deterministic model of bact erial dynamics in a pipe carrying potable water, The SANCHO model simu lates the response of fixed and free bacteria in the system to the con centrations of chlorine and organic substrate entering the system. The authors tested the model on seven full-scale distribution systems and made a study of the error distribution between measured values and th e model's predicted values. Various simulation examples demonstrate th e usefulness of the model for determining a bacterial regrowth control strategy for distribution systems. Coupled with residence time calcul ation software, the SANCHO model may become an important decision-maki ng tool in the management of water distribution systems. The model is particularly useful in that it can help define the reduction threshold s for biodegradable dissolved organic carbon required to maintain a gi ven network's quality objectives as a function of the residence time o f the water in the system.