Measuring the Resiliency of the Manhattan Points of Entry in the Face of Severe Disruption

Abstract

Problem statement: Resilient infrastructure systems are able to continue to provide the expected service levels following disruptive events. Implementing resiliency in infrastructure systems requires knowledge of the current resiliency of the system and a methodology by which different resiliency strategies can be evaluated. In the transportation infrastructure in particular, disruptions cause delays, which will in turn incur substantial economic losses and environmental damages. Approach: The Networked Infrastructure Resiliency framework (NIRA) is proposes to assess the resiliency of the road network that connects Manhattan in New York City to the rest of the regions. The framework proposes to create a network model of the system onto which hypothetical disruptions can be introduced and then to measure resiliency as the impact of disruptions on the performance measures of the system. One of the key performance measures of the transportation infrastructure system is the travel time; hence, the base resiliency of the system is measured as the ratio of the travel time preceding a disruption to the travel time following a disruption. Different resiliency strategies that improve the system’s resiliency can be evaluated through the use of decision tree analysis. Results: The proposed NIRA framework is a novel approach for assessing the resiliency of networked infrastructure system by measuring the impact of disruptions on the system’s performance measures. In road transportation networks, such as that connecting Manhattan entry points, resiliency is achievable through reducing the vulnerability of the system and increasing its adaptive capacity. Conclusion: One vulnerability reduction strategy is the clever assignment of vehicles to other routes in the network. The adaptive capacity of the system is enhanced through the deployment of other parallel systems such as ferries.