ABSTRACT
When modelling critical infrastructure, it is important to account for the effects of interdependencies. Although there is much literature on how to account for interdependencies, there is a shortage of real-world examples. In an effort to increase the number of real-world examples, a model of the interdependent power and water systems of the Caribbean island of St Kitts has been developed. System dependencies arise due to electrically powered water pumps within the water system. Given the location of the island, it is not uncommon for it to encounter tropical storms, which may result in disruptions to the island’s power system. Depending on the severity of the disruption to the power system, the effects may be able to propagate, through the dependencies, into the water system. The developed model uses the track and wind speed of past and simulated hurricanes, or up to date weather predictions, to simulate possible disruptions to the island’s power system. Any propagation of these disruptions to the water system through the interdependencies are also simulated. The recent occurrence of hurricane Maria provides a useful case study to compare the output of the coupled system model with the actual effects that resulted due to the hurricane. The models are run with the known track and wind speeds of hurricane Maria. The predicted disruptions to the power system, as well as the cascading effects throughout the water system are then compared to the actual disruptions exhibited in the interdependent systems. The results can be used to validate the model and give an indication if improvements to the current model can be made.
