AWWA WQTC69363

The assessment of the public health risk associated with intrusion in distribution systems requires a reliable transient analysis model that simulates low and negative pressures accurately. For three low pressure events resulting in negative pressures, field pressure data are compared in this study, with modeling results in a full-scale distribution system. Although the numerical model is generally in good agreement with the field pressure data, it tends to overestimate the negative pressure for downsurge events. Field data are recommended to confirm the transient modeling output if such a model is to be used to evaluate the risks associated with transient intrusion events in water mains. Includes 11 references, figures.