Building network-level resilience to resource disruption from flooding: Case studies from the Shetland Islands and Hurricane Sandy

Abstract

Flood events, at a range of scales, have led to disruption of resources such as water, food, materials and goods are vital to the safety, health and livelihoods of individuals and communities. Increasing interdependencies across infrastructures and supply chains pose substantial challenges for those seeking to move resources, and flood risk managers aiming to reduce the disruption to resource movements before, during and after a flood event. This paper introduces a quantitative resource model that embeds input-output relationships of supply and demand within a spatial network model which enables the impacts of a spatial hazard, such as a flood, to be evaluated. The model has been tested in the Shetland Islands and New York City. The analysis supports observations that a single flood event can disrupt the movement of resources far beyond the flooded area. Disruption of critical sectors can rapidly lead to collapse of the entire system given certain conditions. Resource management strategies, such as diversifying supply chains, reduced clustering of industry and storing supplies locally are shown to reduce the magnitude of the initial impact, and slow the propagation of the disruption through the system-providing useful insights to flood risk managers and planners.