Critical infrastructure systems: A case study of the interconnectedness of risks posed by Hurricane Sandy for New York City

The goal of this paper is to investigate the impact of Hurricane Sandy from the perspective of interdependence among different sectors of critical infrastructure in New York City and to assess the interconnected nature of risks posed by such a hurricane. Critical areas and sectors where interdependent risks led to a catastrophic cascading effect are identified. This study uses indirect damages of each sector to estimate the degree of interdependence among the sectors.

The study examines the impact of the hurricane on different critical infrastructures by combining hazard maps of actual inundation areas with maps of critical infrastructure. The direct damages of each sector are calculated from the inundation areas in the flood map. The indirect damages are estimated by considering the areas that were not inundated but affected by Sandy through the interconnected infrastructure. The electricity sector was the key sector to propagate risks to other sectors. The examination of new initiatives to increase the resilience of critical infrastructures in New York City after Sandy reveals that these initiatives focus primarily on building hard infrastructures to decrease direct damages. They understate the importance of interdependent risk across sectors. Future disaster risk reduction strategies must address interdependent infrastructures to reduce indirect damages.

This document is an input paper of the 2015 Global Assessment Report on Disaster Risk Reduction.