Resilience Quantification of Nonstationary and Compounding Threats

Technological advancements and management adaptations have improved engineered systems functions in response to flooding. Other natural and anthropogenic disturbances such as pandemics, utility hijacking, infrastructure destruction, and biochemical releases can stress a system beyond acceptable limits or in ways not previously conceived. Such threats can be direct or indirect and often result in large-scale disruption to the critical functions of the system. Traditional risk management approaches, while effective for known and predictable threats, are not adequate preparation for compound disturbances that are often unpredictable and not well defined. These approaches are additionally flawed when applied to non-stationary threats such as future coastal flooding impacted by sea level rise and changing riverine inflows. Rather, a resilience-based approach is required.

Resilience-based approaches acknowledge that multiple disruptions to the system will occur while focusing on the recovery and maintenance of critical functions such as interaction of impending hurricanes and evacuation complications due to pandemic. The system can be stressed with multiple disturbances to determine its capacity to resist and recover. Analysis of these capacities or subsequent failures can then be used determine the resilience of the system and provide insight into remedial actions or improvements.

A framework combining hydrologic modeling and network science can be used to determine critical weaknesses in transportation infrastructure due to compounding threats. This determination could be used to address pre-disaster staging by identifying areas that are likely to be isolated and to identify the characteristics of a resilient network to incorporate into future designs. Three locations have been identified for case studies. To analyze resilience under compounded disturbances, flood modeling is combined with hypothetical vehicle bridge failure in New York City, USA. Camp Lejeune, NC, USA was used to analyze resilience under both compound disturbances and non-stationarity. Finally, NAS Gulfport, MS, USA was studied to quantify resilience under non-stationary climate conditions.