Resilient infrastructure networks :managing the impacts of disruptive events on resource movements

Abstract

Interdependencies between infrastructures which enable the flow resources have the potential to increase the vulnerability of interconnected systems of supply chains to disruption via cascading mechanisms. These interactions are poorly understood as there are limited observations whilst the movement of resources can occur at many spatial scales. It is a complex problem because of both the number of components and the dynamic nature of the systems that allow these to move around. To analyse the disruption of resource flows within interdependent systems, this paper introduces a resource model that pulls together two established modelling methodologies: input-output modelling and network analysis. Data on supply, demand and flows are typically only provided at coarse spatial scales, so an important development was the disaggregation of regional economic input-output data into smaller spatial units. The model was tested using a case study of Lerwick in the Shetland Islands. It was found, when flood defences were taken into account, the level of risk from storm surges of various magnitudes was low. The model was able to highlight unknown linkages and reaffirm an increase in vulnerability caused by Just-in-time management strategies and the clustering of like industries. As part of this a flood risk analysis technique was presented which highlighted the potential impacts of floods of varying magnitudes, as well how the flood protection affected the levels of risk caused by these events. A second case study of the food distribution network in New York was also developed to provide validation through the recreation of the effects post Tropical Storm Sandy. The research provided a rationale for an encouragement of a move away from just-in-time production to take place and halt the fashion of making supply chains leaner. It also encouraged an increase in cooperation to take place between companies to understand the vulnerabilities within their own supply chains.