Resilience for rail systems may be defined by the set of system capabilities that enable the continued or improved functionality of rail systems exposed to multiple types of hazards, including extreme weather events. Assessing the resilience of rail systems and making appropriate investments may reduce the impacts of threats to system users and infrastructure. However, no studies found by the authors to date have proposed a comprehensive set of metrics that address all the commonly cited resilience capabilities: robustness, flexibility, preparedness, survivability, recoverability, adaptive capacity, and transformative capacity. Based on a review of studies across freight, intercity passenger, and urban transit rail systems, metrics for resilience are identified, categorized, and analyzed along the disruption and recovery timeline (from before disruption occurrence to long after system recovery). The intent of reviewing such a diverse set of rail system studies is to find appropriate metrics across different agencies, types of systems, and levels of maturity of the agencies’ resilience-building practices. Building upon the review of rail resilience assessment metrics, this first thrust of this research proposes a rail-specific set of metrics to quantify resilience capabilities along the disruption and recovery timeline. These metrics can highlight what interventions can enhance each resilience capability for improved disruption response. The second thrust of this research applies the multi-capability resilience assessment approach to MARTA.
Additionally, although resilience and sustainability assessments may provide advantageous information to decision makers in the rail industry, there is no formalized framework for integrating such assessments in rail practices in the US. The third thrust of this research presents a framework to integrate resilience and sustainability into rail planning and resource allocation decision making. This element supports investments in rail to prepare for extreme events, protect the natural environment, enhance economic competitiveness, and improve quality of life. The study could be useful for agencies looking to assess the sustainability or quantify the resilience of a rail network. More broadly, this study may be of interest to transportation practitioners, policy makers, and other stakeholders looking to better characterize transportation resilience by considering physical and organizational capabilities.
