Transportation Research Board Special Report 356

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International Standard Book Number-13: 978-0-309-73161-4
International Standard Book Number-10: 0-309-73161-5
Digital Object Identifier: http://doi.org/10.17226/28591

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COMMITTEE ON DATA, METRICS, AND ANALYTIC METHODS FOR ASSESSING EQUITY IMPACTS OF SURFACE TRANSORTATION INVESTMENTS: PHASE 2 STUDY TO SUPPORT STATE AND LOCAL DECISION MAKING

DEB A. NIEMEIER (NAE) (Chair), Clark Distinguished Chair in Energy and Sustainability, University of Maryland, College Park

ELIZABETH ALDEN, Executive Director, Hillsborough Transportation Planning Organization, Tampa, Florida (retired)

JESUS M. BARAJAS, Associate Professor, Department of Environmental Science and Policy, University of California, Davis

DEANNA BELDEN,¹ Senior Research Scientist, Mobility Division, Texas A&M Transportation Institute

AHMED EL-GENEIDY, Professor, School of Urban Planning, McGill University

RONALD C. HALL, Transportation Program Manager, Upper Great Plains Transportation Institute, North Dakota State University

ANNA ROACH, Executive Director and Chief Executive Officer, Atlanta Regional Commission

KELLY C. RODGERS, Senior Transportation Planner, Climate Friendly and Equitable Communities Program, Oregon Department of Transportation

GREGORY ROWANGOULD, Associate Professor, Department of Civil and Environmental Engineering, University of Vermont

Study Staff

MELISSA WELCH-ROSS, Study Director

THOMAS R. MENZIES, JR., Director, Consensus and Advisory Studies, Transportation Research Board

TIMOTHY B. MARFLAK, Program Coordinator

CLAUDIA SAULS, Program Coordinator

Consultant

SARAH JO PETERSON, 23 Urban Strategies, LLC

Reviewers

This Consensus Study Report was reviewed in draft form by individuals chosen for their diverse perspectives and technical expertise. The purpose of this independent review is to provide candid and critical comments that will assist the National Academies of Sciences, Engineering, and Medicine in making each published report as sound as possible and to ensure that it meets the institutional standards for quality, objectivity, evidence, and responsiveness to the study charge. The review comments and draft manuscript remain confidential to protect the integrity of the deliberative process.

We thank the following individuals for their review of this report:

EVELYN BLUMENBERG, University of California, Los Angeles

DAVID EDERER, U.S. Centers for Disease Control and Prevention

RHONDA FAIR, Oklahoma Department of Transportation

YINGLING FAN, University of Minnesota-Twin Cities

STEVEN FARBER, University of Toronto

MATTHEW FREEDMAN, University of California, Irvine

STEVEN POLZIN, Arizona State University

PRAGATI SRIVASTAVA, Memphis Metropolitan Planning Organization

ELIZABETH WILLIAMS, Massachusetts Department of Transportation

Although the reviewers listed above provided many constructive comments and suggestions, they were not asked to endorse the conclusions or recommendations of this report nor did they see the final draft before its release. The review of this report was overseen by CHRIS HENDRICKSON (NAE), Carnegie Mellon University, and ROBERT A. MOFFITT (NAS),

Acknowledgments

The committee met nine times from January 2024 to October 2024. Portions of five of these meetings were open to the public and used to gather information relevant to the study. The committee thanks Robert Hampshire, Deputy Assistant Secretary for Research and Technology, and Patricia Hu, Director, Bureau of Transportation Statistics, from the U.S. Department of Transportation for their participation in public meetings during the information-gathering process.

The committee thanks the following individuals for participating in the public briefings and contributing to the committee’s work:

Jacqueline Baldwin-LeClair, Center for Indian Country Development, Federal Reserve Bank of Minneapolis

Ariel Bierbaum, School of Architecture, Planning & Preservation, University of Maryland

Andrew Byrd, Principal, Conveyal

Karen Chapple, City & Regional Planning, University of California, Berkeley, and School of Cities, University of Toronto

Elena Craft, President, Health Effects Institute

Casey Dawkins, School of Architecture, Planning & Preservation, University of Maryland

David Ederer, Epidemiologist, Physical Activity and Health Branch, U.S. Centers for Disease Control and Prevention

Yingling Fan, Professor of Urban and Regional Planning and Associate Dean for Faculty, Humphrey School of Public Affairs, University of Minnesota

Yonah Freemark, Metropolitan Housing and Communities Policy Center, Urban Institute

Richard Frenette, President, BF Strategies

Cat Goughnour, Assistant Secretary, Just Communities, Office of the Secretary, Maryland Department of Housing and Community Development

Betsy Harvey, Transportation Equity Program Manager, Central Transportation Planning, Boston Region Metropolitan Planning Organization

Wendy Heaps, Senior Policy Analyst, Office of Policy, Performance and Evaluation, Office of the Director, U.S. Centers for Disease Control and Prevention

Junfeng Jiao, Community and Regional Planning, The University of Texas at Austin

Ashby Johnson, Executive Director, Capital Area Metropolitan Planning Organization, Austin, Texas

Alex Karner, Associate Professor, Community and Regional Planning, The University of Texas at Austin

Eric Lind, Director, Accessibility Observatory, University of Minnesota

Kate Lowe, Associate Professor of Urban Planning and Policy, University of Illinois Chicago

Samuel Marshal, Data & Performance Management Advisor, City of Seattle, Department of Transportation, Asset & Performance Management

Mary Wolfe McKinley, Associate Director of Research Innovation & Development, Center for Health Equity Research, University of North Carolina at Chapel Hill

Andrew Owen, Lead Researcher, Accessibility Observatory, University of Minnesota

Matthew Palm, Department of City and Regional Planning, The University of North Carolina at Chapel Hill

Ruth Steiner, Department of Urban and Regional Planning & Center for Health and the Built Environment, College of Design, Construction & Planning, University of Florida

Anson Stewart, Project Lead, Analysis and Research, Conveyal

Nicole Tyler, Director of Equitable Transportation, PennDOT

Emily Wornell, Indiana Communities Institute, Ball State University

The committee thanks Hannah Twaddell for preparing a commissioned paper on current practices for assessing equity.

Melissa Welch-Ross, Senior Program Officer, managed the study and assisted the committee in the preparation of this report with research and writing support from Sarah Jo Petersen, 23 Urban Strategies, LLC. Thomas

Contents

PREFACE

ACRONYMS AND ABBREVIATIONS

EXECUTIVE SUMMARY

1 INTRODUCTION

Extending Performance-Based Planning

Study Origins and Charge

Committee Scope and Approach

Report Organization

2 A FRAMEWORK FOR CONNECTING TRANSPORTATION TO SOCIETAL OUTCOMES

An Evolving Understanding of Equity

Causal Chain Analysis and Transportation’s Role in Societal Outcomes

Operationalizing Transportation Equity Metrics

Access to Destinations

Environmental Justice and Public Health

Chapter Summary

3 A REVIEW OF CURRENT PRACTICE, DATA, AND METRICS

Commonly Used Indicators and Metrics

How Metrics Are Used

Equity Analysis and American Indian/Alaska Native Peoples and Tribal Governments

Key Characteristics and Considerations for Equity Indicators and Metrics

Using Qualitative Information as an Indicator or Metric

Chapter Summary

4 EMERGING PRACTICES AND INNOVATIONS THAT HOLD PROMISE

Proximity to Destination Indicators

Transportation Insecurity as an Equity Metric

Environmental Justice and Public Health Burdens

Chapter Summary

5 VISION, RECOMMENDATIONS, AND FUTURE RESEARCH NEEDS

Recommendations

Implementation Considerations for American Indian/Alaska Native Peoples and Tribal Governments

Suggestions for Pending Pilot Testing

APPENDIX: STUDY COMMITTEE BIOGRAPHICAL INFORMATION

Preface

This report is the second in a series of three study reports of the National Academies of Sciences, Engineering, and Medicine to support consideration of equity in decisions about surface transportation investments at federal, state, and local levels of government. In November 2021, Congress passed the Infrastructure Investment and Jobs Act, later renamed the Bipartisan Infrastructure Law, which included significant new federal funding for both formula and discretionary surface transportation programs. It also contained many provisions to advance equity in transportation, including increased funding for tribal transportation and public transit and the creation of numerous equity-oriented competitive grant programs, including programs to upgrade the accessibility of transit rail systems for people with disabilities, reconnect neighborhoods isolated by transportation infrastructure, and fund projects to benefit communities who have experienced disadvantages that may persist. The Transportation Research Board (TRB) Executive Committee elected to sponsor a study that would provide recommendations to the U.S. Department of Transportation (USDOT) on how to best elevate equity in transportation decision-making processes. USDOT’s Office of the Assistant Secretary for Research and Technology, in recognition of the value that such advice could provide to the department in shaping its many new and redesigned surface transportation funding programs, matched the funding that the TRB Executive Committee offered to fully fund a study. Consequently, USDOT’s competitive grant programs were the focus of that study committee’s report, Elevating Equity in Transportation: Recommendations for Federal Grant Programs.

In the Consolidated Appropriations Act of 2022, Congress called on USDOT to sponsor two TRB studies on equity metrics and analytic tools applicable to a wider array of surface transportation funding programs.¹ This report is the culmination of a consensus study to advise on metrics and tools that warrant further study. It will be followed by a subsequent phase to pilot test this study’s recommendations.

To conduct this study, the National Academies appointed a multidisciplinary committee of nine experts with experience in state and local transportation planning and policy, urban and regional planning and policy, environmental justice analysis, statistics and metrics, qualitative assessment methods and public engagement, and transportation in underserved communities and tribal lands. This report represents the consensus efforts of these nine individuals, who served uncompensated in the public interest. Their biographical information is provided in the Appendix.

The study committee began its information gathering by meeting with USDOT officials to learn more about their interest in the study. During its additional information-gathering sessions, the committee considered an array of topics, including the following:

• Current practices used to assess equity and environmental justice outcomes by state departments of transportation and metropolitan planning organizations;
• Uses of data and metrics in transportation decision making;
• Equity outcomes considered in fields of education, health, housing, and studies of economic opportunity;
• Research on how transportation affects education, health, housing, and economic opportunity outcomes;
• Definitions of the populations of interest, including people in “areas of persistent poverty” or who are “historically disadvantaged”;
• Data sources and methods for measuring transportation experiences; and
• Community-informed approaches to understanding transportation needs.

The study committee and TRB wish to thank the many individuals who participated in these public sessions and who are identified in the Acknowledgments section.

Acronyms and Abbreviations