Simulation and vulnerability assessment of water distribution networks under deliberate contamination attacks

Abstract

ABSTRACT This work proposes a modeling framework to quantify the effects of deliberate organic contamination events on water distribution systems. A bacterial regrowth model and a first parallel chlorine decay model were combined to describe the biochemical water species kinetics during a deliberate contaminant injection consisting of organic (TOC) and bacterial loads. Several attacks were modeled using EPANET-MSX. The impact of each attack was quantified using vulnerability indexes measuring the number of consumers affected and other metrics. These vulnerability indexes were then used to depict the network’s response to a potential threat and identify the most critical areas of the network. A sensitivity analysis was also performed to determine the network’s sensitivity to three dynamic network variables (mass injection, injection duration, and organic carbon concertation in water). An increase on bacterial populations was observed during the contaminant spread to the network, which in turn signals additional health risk to consumers.