Modeling Pipe Damages in Water Distribution Systems

This presentation examines the physical mechanisms that cause structural damage in water distribution pipes and outlines modelling approaches for estimating resulting leakage. Common failure drivers include installation defects such as improper joint assembly, aging related material deterioration including corrosion and embrittlement, ground movement from settlement or seismic activity, pressure transients such as water hammer, and temperature induced stresses like frost loading and differential thermal contraction. These mechanisms can result in well-known crack geometries: annular disengagement, round cracks, longitudinal cracks, and localized wall loss. Each geometry has an associated formulations for estimating the effective orifice area governing leakage flow rates. The presentation reviews key hydraulic modelling approaches, including orifice based discharge equations and the Fixed and Variable Area Discharge (FAVAD) concept, which captures both fixed and pressure responsive leak areas. Recent implementations in EPANET integrate these formulations using parameters defined per unit pipe length, enabling more realistic simulation of distributed leakage within distribution networks.

 Click here to download a static PDF version of the presentation.