Head-driven simulation based reliability assessment of water supply networks

This paper describes reliability assessment of water supply networks based on head-driven simulation of hydraulic performance of the system. The widely accepted definition of reliability measure is used as the ratio of the available outflow to the total required demand. It is strongly believed that the head-driven analysis of the hydraulic equations of the system is the best way to obtain the values of nodal and network shortfall. It can easily address the effects of any mechanical and/or hydraulic failures on the hydraulic behaviour of the system. The reliability index uses up to two simultaneous link failures. Through a test example the accuracy and efficiency of the new methodology are presented. It is illustrated that using head driven analysis which consider the tendency of the consequence of inadequate pressures being localised, leads to remove the main weaknesses of the existing reliability measures which do not address the strong interdependencies between the reliability of demand nodes