A Response Methodology for Reducing Impacts of Failure Events in Water Distribution Networks

This paper presents a methodology for developing efficient and effective operational, short time response to a water distribution system (WDS) pipe failure event (e.g. pipe burst). In general, management and response to failures in WDS are performed by isolating the failure, estimating the impacts of isolation on the customers and recovering the affected part of the system by restoring the flows and pressures to normal conditions. The isolation is typically achieved by manipulating the nearby on/off valves whilst a hydraulic simulator (such one used in EPANET2.0) is used for estimating impacts. The recovery, which is the focus of this work, involves selecting a combination of suitable operational interventions from a number of possible choices to bring the water into the isolated area and restore normal flow conditions. The options considered here include valve manipulations, changing the pressure reducing valve's (PRV) outlet pressure and installation and use of a temporary overland bypasses from a nearby hydrant(s). The optimal mix of interventions is identified by using a multi-objective optimization algorithm integrated with the pressure driven hydraulic solver. The optimization is driven by the minimization of the negative impact on the customers and minimization of the corresponding number of operational intervention activities (which acts as a surrogate for operational costs). The above methodology has been applied to a real world water distribution network of C-Town. The results obtained demonstrate the effectiveness of the proposed methodology in identifying the Pareto optimal intervention strategies that could be ultimately presented to the control room operator for making a suitable decision. (C) 2016 The Authors. Published by Elsevier Ltd.