Equity Considered Infrastructure Decision-Support for Improved Community Resilience to Natural Hazards
Advisor: Professor Eun Jeong Cha
Abstract
Infrastructure provides critical services to a community and its provision or absence greatly dictates a community’s impacts, functionality, and resilience post hazard. However, the impacts of infrastructure failures after hazards are not uniform across a community but are often disproportionately clustered among vulnerable populations (e.g., minority, low-income) who are also often serviced by infrastructure more prone to failures only to exacerbate the likelihood of disproportionate impacts. Community resilience necessitates the holistic support of a community. If equity considerations, such as reducing these inequitable impacts, are not integrated into infrastructure decisions (e.g., retrofit, restoration) then infrastructure is not equitably serving a community nor is community resilience best supported. This dissertation presents novel equity-based infrastructure decision support tools for improved community resilience to natural hazards.
Equity is not easily defined but is best viewed as being defined by five dimensions each with their own definition: recognitional, distributional, restorative, transgenerational, and procedural. This dissertation appraises the current state of infrastructure decision support and their amenability to accommodate all equity dimensions. This work further identifies current gaps in equity-based infrastructure decision support. While four of the five dimensions are greatly lacking in support tools, this dissertation primarily focuses on two dimensions. First, an innovative infrastructure outage impact criticality analysis that enables the assessment of infrastructure components from a social impact perspective in support of recognitional equity is derived. The framework is built upon the integration of a network analysis approach with social impact models. Secondly, an equity retrofit metric to quantify the inequity in service provision to vulnerable population subsets in support of restorative equity is developed. The metric is derived upon Theil’s T and supplemented with network reliability quantifications for the infrastructure application. Further, the metric is utilized to compare distributional equity-based and restorative equity-based retrofitting for Galveston’s electric network. Thirdly, an equity restoration metric to prioritize restoration for those who face the most outage burden is developed along with methods to characterize this outage burden in support of restorative equity. This metric is derived upon the individual Theil’s T. This metric is applied to restoration for Lumberton, NC’s electric distribution network. The equity-conscious decision support tools of this dissertation orient the investigated decisions to improve equity, yet these tools can also be utilized in other equity-based infrastructure decision applications, such as resource allocation, management, and operational decisions. Ultimately, the decision support tools of this dissertation support the overall decision paradigm shift from one that is purely life safety to one that is community resilience and equity conscious.
