AWWA JAW64050

In the US regulatory climate of renewed focus on water quality in the distribution system, the role of modeling has become increasingly important. The authors review the current state of model calibration guidelines in the United States and compare US practices with calibration and model development in the United Kingdom. This research also provides for the first time statistical calibration accuracies for several extended period simulation (EPS) water distribution models. Seven case models were developed and calibrated using only trial-and- error methods (iterative calibration). The authors demonstrate what is required to achieve a calibrated water distribution system model and provide a benchmark for calibration accuracies for models used in long-term planning. Utilities can use this information as a guide to evaluate calibration accuracies of their own models. The benefit of improved calibration accuracies must be weighed against the costs of obtaining additional and more-precise field data and the expense of efforts to improve model calibration accuracies. Includes 8 references, tables, figures.