Graph-Based Hydraulic Vulnerability Assessment of Water Distribution Networks

Presented herein is a methodology for the seismic and hydraulic assessment of the re-liability of urban water distribution networks (UWDN) based on general seismic assessment standards, as per the American Lifelines Alliance (ALA) guidelines, localized historical records of critical risk-of-failure metrics pertaining to the specific UWDN under assessment, and hydraulic simulations using adapted EPANET models. The proposed methodology is applicable to UWDN under either normal or abnormal operating conditions (such as intermittent water supply), and the assessment of reliability incorporates data of past non-seismic damage, the vulnerabilities of the network components against seismic loading, hydraulic modelling, and the topology of an UWDN. The network reliability is subsequently assessed using Graph Theory, while the system reliability is calculated using Monte Carlo simulation coupled with a hydraulic analysis identifying various methodology options for hydraulic quantity evaluation and hence hydraulic network performance. The methodology proposed is demonstrated on a real-scale district metered area (DMA) in a city-wide UWDN.