Developing an equity-focused metric for quantifying the social burden of infrastructure disruptions

Communities in the United States are increasingly dependent upon aging infrastructure systems and challenged by more frequent and intense extreme weather events due in part to climate change. However, prioritizing resilience-related investments in these systems is hindered by the lack of performance metrics that objectively quantify the societal outcomes of infrastructure disruptions, such as power or water outages. This article outlines the process of developing an equity-focused resilience metric that captures the social consequences of infrastructure service disruptions on households. Theoretically grounded in the Capabilities Approach (CA) theory of human development, this metric focuses on estimating the burden of post-event adaptations taken by households to maintain their basic capabilities (e.g., ability to access food and water) and fulfill important household functionings (e.g., maintaining health and well-being). A travel cost method (TCM) that considers travel-related expenses, direct out-of-pocket expenses, and opportunity costs is presented as a way to measure the value of locations (e.g., grocery stores, emergency shelters, etc.) that provide services that enable households to maintain capabilities. A gravity-weighted model of accessibility is also discussed as a way to capture the value of having multiple potential service locations from which to choose and offers a way to capture important factors impacting a household's ability to access important goods and services during outages. The proposed social burden metric equation incorporates the valuation principles of the TCM into the framework of the gravity model, resulting in a novel metric with strong methodological heritage. The article concludes by discussing the types of data needed to populate the proposed metric and future applications of this work that could inform the resilient infrastructure investments and planning necessary to mitigate the social burdens of power outages on vulnerable populations.