Understanding infrastructure dependency during natural hazards events for actionable disaster responses

One major focus of the Sendai Framework for Disaster Risk Reduction 2015-2030 is to “Build Back Better” in recovery, rehabilitation and reconstruction to achieve disaster risk reduction and resilient communities. While forecasting and decision-making tools help predict and understand future impacts of natural hazards, given the interdependency of infrastructures, predictive approaches fail to identify long-term impacts of an extreme event on infrastructures and recovery time. As seen following hurricane Maria's impacts in Puerto Rico, the failure of power infrastructure not only isolated the island from the outside world, but also contributed to the lack of supply of clean and filtered water, and sewage treatment. While there have been several decision support tools that look at the vulnerability and resilience of different critical infrastructure systems as a single system and/or coupled systems, there still exists a gap in quantifying system vulnerabilities due to cascading impacts. In this paper, we present a conceptual framework for quantifying dynamic resilience of interdependent infrastructure systems. The proposed approach should provide the knowledge needed for stakeholders and decision-makers to prioritize their efforts during recovery to build resiliency.