Simplified procedure for water distribution networks reliability assessment

This work describes a simple procedure for the analysis of water distribution system (WDS) performance. It is based on the reliability assessment of a WDS during failure states resulting from the unavailability of a pipe (maintenance or repair), taking into account the probability of the failure events. The procedure may consider changes in daily demand by using patterns defined to represent seasonal trends. Applying this method to a network with around 200 pipes demonstrates its usefulness, especially when the aim is to objectively compare different design solutions. The procedure takes also into account variations in design parameters such as an increase in water demand and/or a drop in hydraulic conductance resulting from pipe lining degradations (corrosion or deposits).