The Effect of Demand Uncertainty on Transient Propagation in Water Distribution Systems

A method of characteristics-based computational model of a straight reservoir/pipe/valve system was created as a very simple rep- resentation of a small residential water distribution system. The model was used to assess transient modelling and analysis errors which occur due to demand aggregation and uncertainty. The effect of aggregating demand from the small network of residences was investigated and found to be most significant when the number and distribution of the demands was randomly varied. The inclusion of service connection pipes was also investigated; in this case leading to a higher peak head and a phase-shift in the head oscillations, which increased over time; this demonstrates the importance of modelling complete systems with high levels of accuracy.