Consensus Study Report

NATIONAL ACADEMIES PRESS 500 Fifth Street, NW Washington, DC 20001

This activity was supported by the Gulf Research Program of the National Academies of Sciences, Engineering, and Medicine. Support for the work of the Board on Environmental Change and Society is also provided by a grant from the National Science Foundation (Award No. BCS-2055602). Any opinions, findings, conclusions, or recommendations expressed in this publication do not necessarily reflect the views of any organization or agency that provided support for the project.

International Standard Book Number-13: 978-0-309-70872-2
International Standard Book Number-10: 0-309-70872-9
Digital Object Identifier: https://doi.org/10.17226/27213
Library of Congress Control Number: 2024934365

Cover image: Copyrighted by the Louisiana Sea Grant College Program.

This publication is available from the National Academies Press, 500 Fifth Street, NW, Keck 360, Washington, DC 20001; (800) 624-6242 or (202) 334-3313; http://www.nap.edu.

Copyright 2024 by the National Academy of Sciences. National Academies of Sciences, Engineering, and Medicine and National Academies Press and the graphical logos for each are all trademarks of the National Academy of Sciences. All rights reserved.

Printed in the United States of America.

Suggested citation: National Academies of Sciences, Engineering, and Medicine. 2024. Community-Driven Relocation: Recommendations for the U.S. Gulf Coast Region and Beyond. Washington, DC: The National Academies Press. https://doi.org/10.17226/27213.

The National Academy of Sciences was established in 1863 by an Act of Congress, signed by President Lincoln, as a private, nongovernmental institution to advise the nation on issues related to science and technology. Members are elected by their peers for outstanding contributions to research. Dr. Marcia McNutt is president.

The National Academy of Engineering was established in 1964 under the charter of the National Academy of Sciences to bring the practices of engineering to advising the nation. Members are elected by their peers for extraordinary contributions to engineering. Dr. John L. Anderson is president.

The National Academy of Medicine (formerly the Institute of Medicine) was established in 1970 under the charter of the National Academy of Sciences to advise the nation on medical and health issues. Members are elected by their peers for distinguished contributions to medicine and health. Dr. Victor J. Dzau is president.

The three Academies work together as the National Academies of Sciences, Engineering, and Medicine to provide independent, objective analysis and advice to the nation and conduct other activities to solve complex problems and inform public policy decisions. The National Academies also encourage education and research, recognize outstanding contributions to knowledge, and increase public understanding in matters of science, engineering, and medicine.

Learn more about the National Academies of Sciences, Engineering, and Medicine at www.nationalacademies.org.

Consensus Study Reports published by the National Academies of Sciences, Engineering, and Medicine document the evidence-based consensus on the study’s statement of task by an authoring committee of experts. Reports typically include findings, conclusions, and recommendations based on information gathered by the committee and the committee’s deliberations. Each report has been subjected to a rigorous and independent peer-review process and it represents the position of the National Academies on the statement of task.

Proceedings published by the National Academies of Sciences, Engineering, and Medicine chronicle the presentations and discussions at a workshop, symposium, or other event convened by the National Academies. The statements and opinions contained in proceedings are those of the participants and are not endorsed by other participants, the planning committee, or the National Academies.

Rapid Expert Consultations published by the National Academies of Sciences, Engineering, and Medicine are authored by subject-matter experts on narrowly focused topics that can be supported by a body of evidence. The discussions contained in rapid expert consultations are considered those of the authors and do not contain policy recommendations. Rapid expert consultations are reviewed by the institution before release.

For information about other products and activities of the National Academies, please visit www.nationalacademies.org/about/whatwedo.

COMMITTEE ON MANAGED RETREAT IN THE U.S. GULF COAST REGION

JANICE BARNES (Co-Chair), Founding and Managing Partner, Climate Adaptation Partners

TRACIE T. SEMPIER (Co-Chair), Coastal Resilience Engagement Specialist, Mississippi–Alabama Sea Grant Consortium

KAYODE O. ATOBA, Associate Research Scientist, Institute for a Disaster Resilient Texas, Texas A&M University

GARY S. BELKIN, Director, Billion Minds Project, Columbia University Mailman School of Public Health

DEBRA M. BUTLER, Executive Director, American Society of Adaptation Professionals

CRAIG E. COLTEN, Professor Emeritus, Louisiana State University

KATHERINE J. CURTIS, Associate Director and Professor of Community and Environmental Sociology, Center for Demography and Ecology, University of Wisconsin–Madison

HARRIET FESTING (Resigned December 2022), Executive Director and Co-Founder, Anthropocene Alliance

LYNN R. GOLDMAN, Michael and Lori Milken Dean and Professor of Environmental and Occupational Health, Milken Institute School of Public Health, George Washington University

E. BARRETT RISTROPH, Owner, Ristroph Law, Planning, and Research

CATHERINE L. ROSS, Regents Professor and Harry West Professor of City and Regional Planning, and Director, Center for Quality Growth and Regional Development, Georgia Institute of Technology

GAVIN P. SMITH, Professor, Department of Landscape Architecture and Environmental Planning, North Carolina State University

NATALIE L. SNIDER, Science Integrator, University of Maryland Center for Environmental Science Integration and Application Network

COURTNEY S. THOMAS TOBIN, Associate Professor of Community Health Sciences, Associate Dean for Equity, Diversity, and Inclusion, Fielding School of Public Health, and Faculty Associate, Ralph J. Bunche Center for African American Studies, University of California, Los Angeles

Study Staff

JOHN BEN SOILEAU, Study Director

CHANDRA MIDDLETON, Study Co-Director (until December 2022)

THOMAS F. THORNTON, Board Director

GRACE BETTS, Associate Program Officer

SITARA RAHIAB, Senior Program Assistant

HANNAH STEWART, Associate Program Officer (until October 2023)

BOARD ON ENVIRONMENTAL CHANGE AND SOCIETY

KRISTIE L. EBI (Chair), Professor, Center for Health and the Global Environment, University of Washington, Seattle

BILAL M. AYYUB, Professor and Director, Center for Technology and Systems Management, Department of Civil and Environmental Engineering, University of Maryland

EDUARDO S. BRONDIZIO, Distinguished Professor of Anthropology, Indiana University, Bloomington

LISA DILLING, Associate Chief Scientist, Environmental Defense Fund

KENNETH GILLINGHAM, Professor, Yale School of the Environment, Yale University

MARY H. HAYDEN, Research Professor, Lyda Hill Institute for Human Resilience, University of Colorado

LORI M. HUNTER, Professor of Sociology and Director, Population Research Program, Institute of Behavioral Science, University of Colorado Boulder

STEPHEN H. LINDER, Professor and Vice Chair, Department of Management, Policy and Community Health, and Director, Institute for Health Policy, University of Texas Health Science Center; Co-Director, Community Engagement Core, Gulf Coast Center for Precision Environmental Health

GLEN M. MACDONALD, John Muir Memorial Chair and Distinguished Professor, University of California, Los Angeles

GARY E. MACHLIS, Professor of Environmental Sustainability, College of Behavioral, Social and Health Sciences, Clemson University

BENJAMIN PRESTON, Director, Senior Policy Researcher, and Professor, RAND Corporation

JESSE RIBOT, Professor, School of International Service, American University

JACQUALINE QATALIÑA SCHAEFFER, Senior Project Manager, Alaska Native Tribal Health Consortium

MADELINE SCHOMBURG, Director of Research, Energy Futures Initiative Foundation

BENJAMIN KENNETH SOVACOOL, Professor of Earth and Environment, Boston University

ADELLE DAWN THOMAS, Senior Scientist, Climate Analytics, and Senior Fellow, University of The Bahamas

MICHAEL P. VANDENBERGH, Professor and David Daniels Allen Distinguished Chair in Law, Vanderbilt University Law School

CATHY L. WHITLOCK, Regents Professor Emerita of Earth Sciences, Montana State University

THOMAS F. THORNTON, Director

COMMITTEE ON POPULATION

ANNE R. PEBLEY (Chair), Bixby Chair and Distinguished Professor of Population Studies, Department of Sociology, University of California, Los Angeles

EMILY M. AGREE, Research Professor, Department of Sociology, Krieger School of Arts & Sciences, Johns Hopkins University

DEBORAH BALK, Professor and Associate Director, Institute for Demographic Research, Baruch School of Public Affairs, Baruch College of the City University of New York

COURTNEY C. COILE, Professor of Economics, Wellesley College

SONALDE DESAI, Distinguished University Professor, University of Maryland, and Professor and Centre Director, National Council of Applied Economic Research, New Delhi

DANA A. GLEI, Senior Research Investigator, Georgetown University

ROBERT A. HUMMER, Professor, Department of Sociology, Carolina Population Center, University of North Carolina

SEEMA JAYACHANDRAN, Professor, Department of Economics, School of Public and International Affairs, Princeton University

HEDWIG LEE, Professor of Sociology, Washington University in St. Louis

TREVON D. LOGAN, Hazel C. Youngberg Trustees Distinguished Professor, Department of Economics, The Ohio State University

JENNIFER J. MANLY, Professor, Department of Neurology and the Taub Institute for Research on Alzheimer’s Disease and the Aging Brain, Columbia University Medical Center

JENNA NOBLES, Professor and Associate Director, Department of Sociology, Center for Demography and Ecology, University of Wisconsin–Madison

FERNANDO RIOSMENA, Professor, Sociology and Demography, University of Texas at San Antonio

DAVID T. TAKEUCHI, Associate Dean for Faculty Excellence, School of Social Work, Center for Studies in Demography & Ecology, University of Washington

MALAY MAJMUNDAR, Director

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:

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 HOLLY REED, Queens College of the City University of New York, and CHRIS D. POLAND, Consulting Engineer, Canyon Lake, California. They were responsible for making certain that an independent examination of this report was carried out in accordance with the standards of the National Academies and that all review comments were carefully considered. Responsibility for the final content rests entirely with the authoring committee and the National Academies.

Contents

Preface

Acronyms and Abbreviations

Summary

PART 1: INTRODUCING COMMUNITY-DRIVEN RELOCATION

1 Introduction

RESPONSE TO THE CHARGE

Gulf Coast Communities

Community-Based Organizations

Regional Organizations, Commissions, and Entities

State Agencies

State Legislatures

Municipal, Parish, and County-Level Government Officials

Federal Agencies and Other Audiences

SCOPE OF GEOGRAPHY AND HAZARDS

UNDERSTANDING MANAGED RETREAT

Who Is Doing the Managing?

What Is the Scale of the Proposed Retreat?

What Is the Difference Between Managed Retreat and Other Forms of Relocation?

COMMUNITY-DRIVEN RELOCATION

Disaster Recovery Model Versus Year-Round Support

Alternatives to Relocation

ADAPTATION AND RESILIENCE

Adaptation and Adaptive Governance

Resilience and Adaptive Governance

THE STUDY PROCESS

Study Limitations

REPORT STRUCTURE

2 The Scale of the Threat

THE GULF COAST PHYSICAL ENVIRONMENT AND THE SCALE OF CLIMATE CHANGE

Introduction

Environmental Hazards

Climate Change and Its Impacts

The Causes and Impacts of Subsidence

Industrial Impacts on Regional Flood Risks

Summary: The Scale of Climate Change in the Gulf Coast Region

THE SCALE OF THE CURRENT THREAT OF DISPLACEMENT

Displacement Tracking

Future Displacement

Growing Populations in Areas Susceptible to Environmental Hazards

SUMMARY

CONCLUSIONS

3 Examples of Relocation

INTRODUCTION

A BRIEF HISTORY OF COMMUNITY RELOCATION EFFORTS IN THE UNITED STATES

Early Cases

The Great Midwest Floods of 1993 and FEMA-Supported Relocation

BUYOUTS: CHALLENGES, OPPORTUNITIES, AND LESSONS

Eminent Domain/Forced Relocations

The Dutch Strategy of Bottom-Up, Integrated, and Holistic Flood Risk Reduction

CASE STUDIES

Hurricane Sandy in New York and New Jersey

The Village of Newtok, Alaska

Isle de Jean Charles, Louisiana

Grantham, Australia: 2011 Flash Flood

Tohoku, Japan: The 2011 Great East Japan Earthquake and Tsunami

SUMMARY

PART 2: UNDERSTANDING RELOCATION IN THE GULF REGION

4 Understanding the Gulf Region: Historical Context

INTRODUCTION

ADAPTATION AND MOVEMENT

Indigenous Peoples of the Region and European Contact

ENSLAVEMENT

MIGRATION

HISTORICAL LEGACIES

Political Disenfranchisement

Economic Injustice

Geographic Isolation and the Preservation of Culture

SUMMARY

CONCLUSIONS

5 Current Realities of the Gulf Coast

INTRODUCTION

Gulf Coast Demographics

Gulf Coast Economies and Associated Risks

CLIMATE CHANGE AND RECENT/PROJECTED MIGRATION TOWARD AND AWAY FROM THE COAST

In-Migration to the Gulf Coast Region and Gulf Coastal Shoreline Communities

REASONS WHY PEOPLE LIVE ON THE GULF COAST

Place Attachment

Other Reasons to Remain in Place

COMMUNITY PROFILES

Overview of the Following Profiles

City of St. Petersburg, Florida, Including Pinellas County

Mobile County and Community of Bayou La Batre, Alabama

Harrison County and Community of Turkey Creek, Mississippi

Southeast Louisiana (Lafourche and Terrebonne Parishes)

Port Arthur, Texas

DATA AVAILABILITY ACROSS PROFILES

SUMMARY

CONCLUSIONS

6 Sustaining Community Well-Being: Physical, Mental, and Social Health

INTRODUCTION

A HOLISTIC APPROACH TO WELL-BEING

Capabilities for Subjective Well-Being and Capacities for Action

PRE-EXISTING, CONTINUOUS, AND NEW IMPACTS ON WELL-BEING

Pre-Existing and Long-Term Environmental Health Issues for Gulf Coast Communities

Forms of Mental Health Impacts from Climate Change and Climate-Induced Relocation

Policy Implications

ENHANCING RESILIENCE AND WELL-BEING THROUGH TASK SHARING AND NURTURE EFFECTS

Task Sharing

Nurture Effects

SOCIAL CAPITAL, COMMUNITY COHESION, AND COLLECTIVE EFFICACY

All Resources Matter

PLACE ATTACHMENT, RELOCATION, AND WELL-BEING

Place Attachment, Relocation, and Social Capital

Place Attachment and Destination

SUMMARY

CONCLUSIONS

7 Communication, Participation, and Knowledge

INTRODUCTION

Chapter Overview and Outline

A LACK OF DISCUSSION ABOUT RELOCATION AND A DISTRUST IN GOVERNMENT

Distrust of Government

COMMUNICATION

Communicating Relocation as an Option

Transparency

Language, Literacy, and Cultural Considerations

RISK COMMUNICATION

Mental Models for Risk Communication

PARTICIPATION AND KNOWLEDGE

Linking Social Capital to Participation and Civic Leadership

Power Sharing and Participatory Decision Making: Who Decides?

Co-Production of Community-Driven Relocation

PAR and Practice

Local and Indigenous Knowledge in Participatory Planning

Community Knowledge and Protocols

SUMMARY

CONCLUSIONS

8 Receiving and Originating Communities

INTRODUCTION

RECEIVING COMMUNITIES

Characteristics of Receiving Communities

Identifying Suitable Receiving Areas

Resource Needs for Receiving Communities

ORIGINATING COMMUNITIES

Thresholds

Consolidation and Regionalization

Decommissioning and Restoration

Continuing Access

ORIGINATING AND RECEIVING PARTNERSHIPS

SUMMARY

CONCLUSIONS

PART 3: FUNDING, POLICY, AND PLANNING

9 Landscape of Policy, Funding, and Planning

INTRODUCTION

Nested Scales for Regional Planning

Interrelationship of Funding, Policy, and Planning

FEDERAL AGENCIES, AUTHORITIES, AND POLICIES

Maze of Potential Assistance

Disaster-Related Agencies

Agencies Not Primarily Disaster-Related

Federal Nonfinancial Technical Assistance for Flood Events

STATEWIDE RELOCATION AND PLANNING EFFORTS

National Overview

A Case Study of State Agencies and Buyouts: Texas

REGIONAL COORDINATION IN THE GULF REGION

The Need for and Lack of Regional Coordination

Gulf-Wide and State Planning Agencies and Organizations

LOCAL GOVERNMENTS AND COMMUNITIES

Local-Level Buyout Programs and Planning

Case Study of Applying Land-Use Planning to Address Relocation: Norfolk, Virginia

PRIVATE AND PUBLIC-PRIVATE FUNDING AND PROGRAMS

AN OVERVIEW OF THE MULTI-LEVEL CHANGE NEEDED

SUMMARY

CONCLUSIONS

10 Challenges and Opportunities for Policy

INTRODUCTION

CHALLENGES OF THE EXISTING APPROACH

Communication Challenges

Flood Risk Responsibility

The Role of Insurance

Housing Eligibility Criteria

High-Level Analysis of Complexity, Time, and Post-Buyout Requirements

Economic Justice

OPPORTUNITIES FOR INNOVATION UNDER THE EXISTING LEGAL FRAMEWORK

Knowledge Sharing and Institutional and Peer-to-Peer Learning

Reducing Barriers to Obtaining Grants

Addressing the Cost-Effectiveness Criterion and Buyout Eligibility

Additional Efforts to Increase Fairness in Buyouts

LESSONS TO BE LEARNED FROM OUTSIDE THE UNITED STATES

Buyouts as Part of a National Policy Framework in New Zealand

Threshold-Based Relocation Assistance in Fiji

SUMMARY

CONCLUSIONS

11 Recommendations for Community-Driven Relocation Efforts in the Gulf Region and Beyond

CENTERING WELL-BEING

DEVELOPING AND SUSTAINING LOCAL COLLABORATIONS

Collaborative Planning with Communities

Collaborative Regional Planning

Collaborative Federal Planning

Cross-Sector Collaborations and Capacity Building

Investing in Receiving Communities

STRENGTHENING PREPARATIONS FOR COMMUNITY-DRIVEN RELOCATION

Technical and Planning Assistance

Taking Advantage of Innovative Strategies to Reduce Complexities and Rethink Priorities

Ensuring Equity

References

Appendixes

A Committee Members

B Public Info Session Participants

C Community Profiles

D Key Terms

E Gulf Coast Timeline

Boxes, Figures, and Tables

BOXES

1-1 Statement of Task

1-2 Committee Outreach Activities

4-1 Community Testimonial: Elder Theresa Dardar, Pointe-au-Chien Indian Tribe, Lafourche/Terrebonne Parish

4-2 Community Testimonial: Bette Billiot, the United Houma Nation

5-1 Community Testimonial: Migrating up the Bayou

5-2 Community Testimonial: Cascading Problems—Housing and Transportation

5-3 Community Testimonial: Sea Level Rise, Flooding, and Isolation

5-4 Community Testimonial: Climate-Related Health Concerns

5-5 Community Testimonial: Recent Environmental Disasters and Community Responses and 2021 Piney Point Wastewater Disaster

5-6 Community Testimonial: Cultural Preservation and Relocation

5-7 Community Testimonial: Impacts of Flooding Events and Pollution

5-8 Community Testimonial: Response to Pollution

5-9 Bayou La Batre

5-10 Community Testimonial: Factors Affecting Resilience in the Face of Flooding

5-11 Community Testimonial: Response to Air Pollution and Climate-Related Health Concerns

5-12 Community Testimonial: Environmental Justice

5-13 Community Spotlight: Come Hell or High Water—The Battle for Turkey Creek

5-14 Community Testimonial: Housing and Land Loss

5-15 Community Testimonial: Community Members Understand the Risks, but Still Plan to Stay

5-16 Community Testimonial: Response to Hurricanes

5-17 Community Testimonial: Locals Are Used to Flooding, but Hurricane Ida Brought Damaging Winds, Exposing Community Vulnerabilities

5-18 Community Testimonial: Planning for Protecting Culture Lags Behind Planning for Protecting Land

5-19 Community Testimonial: Cascading Problems—Housing and Transportation

5-20 Community Testimonial: Flooding Complications

5-21 Community Testimonial: Emissions-Related Health Concerns

5-22 Community Testimonial: Residents Have Few Choices

6-1 Workshop Testimonials: Mental Health

6-2 Community Testimonial: Displacement and Mental Health Concerns

6-3 Implications of Health Service Availability for Relocation and Displacement

6-4 Community Testimonial: Bette Billiot, the United Houma Nation

6-5 Cherry Wilmore and Sherry Wilmore, Residents of Houma, Louisiana

7-1 Community Testimonial: Elder Chief Shirell Parfait-Dardar

7-2 Community Testimonials: Distrust in Government

7-3 Community Testimonials: Community-Led Decision Making and Engagement

7-4 Community Testimonials: Challenges for Effective Communication and Outreach

7-5 Community Testimonials: Lack of Resources and Equity

7-6 Community Testimonial: Lack of Communication

7-7 Community Testimonials: Self-Determination and Tribal Sovereignty

7-8 Case: TEK Used to Aid Restoration Decisions

7-9 Case: Tribal Coastal Resilience Index (T-CRI)

8-1 Community Testimonials: Gentrification and the Cost of Living

8-2 Community Testimonials: Community Acceptance

8-3 Community Testimonials: Relocation for Whom?

9-1 Disconnects Among Federal and Other Governments

FIGURES

S-1 The primary focus of this report: the U.S. Gulf Coast Region

1-1 The primary focus of this report: the U.S. Gulf Coast Region

2-1 Gulf of Mexico region showing basic current patterns in the Gulf of Mexico, including the Loop Current

2-2 U.S. 2022 billion-dollar weather and climate disasters

2-3 Coastal Flood Risk Index for tribal communities

2-4 Coastal Hazard Risk Index for Gulf Coast communities

2-5 Social Vulnerability Index score for Gulf Coast communities

2-6 Orleans Parish days with maximum temperature above 95F

2-7 Projected change in daily, 20-year extreme precipitation

2-8 Fluvial (riverine) flood risk

2-9 SLR at 1 foot

2-10 Gulf Coast Coastal Flood Hazard Composite

2-11 High tide flood events are significantly increasing around the United States

2-12 Visualizing high tide flooding with 12 inches of SLR in the Gulf

2-13 Projected storm surge in Louisiana

2-14 Gulf of Mexico subsidence rates

2-15 Two feet of SLR plus vulnerable communities

2-16 Top Map: Change in population less than 1 m above Mean Higher High Water, by county, along the southeastern U.S. coast, 1990–2020. Bottom Map: Percent of Black residents who live below 1 m, divided by percent of all residents who live below 1 m, by county, 2020 Census

3-1 Erosion on the coast of Newtok in 2020

3-2 The first few houses built in Mertarvik, the new site for Newtok Village

3-3 View of Isle de Jean Charles facing northward

5-1 Among coastal regions, the Gulf of Mexico had the highest percentage of the workforce in construction industries and in natural resources, construction, and maintenance occupations

5-2 National Risk Index, Pinellas County, Florida

5-3 National Risk Index, Mobile County, Alabama

5-4 National Risk Index, Harrison County, Mississippi

5-5 National Risk Index, Lafourche and Terrebonne Parishes, Louisiana

5-6 National Risk Index, Port Arthur, Texas

6-1 Conceptual diagram illustrating the exposure pathways by which climate change affects human health

6-2 The Centers for Disease Control and Prevention’s Framework, Building Resilience Against Climate Effects

6-3 Capabilities leveraged in a task-sharing approach

7-1 An example of the psychological, institutional, and practical barriers to relocation from environmentally high-risk areas

7-2 Bonding, bridging, and linking social capital

9-1 Blueprint for FEMA-funded buyouts

9-2 Sources of federal government support for relocation

9-3 Impact of advisory base flood elevations on elevation requirements during post-disaster reconstruction of the Biloxi, Mississippi, peninsula

9-4 A community plan for reinvestment and disinvestment

10-1 Percent change in insurance premiums during year one of Risk Rating 2.0 (current to risk based)

C-1 The 2020 national overall Social Vulnerability Index for Pinellas County, Florida

C-2 The prevalence of adults aged 18+ who reported fair or poor health in 2020 in St. Petersburg, Florida

C-3 Percentages of people that live in the floodplain in Pinellas County, Florida

C-4 Critical facilities in the 100-year floodplain in Pinellas County, Florida

C-5 Risk analysis and poverty in St. Petersburg, Florida

C-6 Environmental Justice Index for St. Petersburg, Florida, compared to the state and nation

C-7 The Environmental Justice Index rank for Pinellas County, Florida

C-8 The 2020 national overall Social Vulnerability Index for Mobile County, Alabama

C-9 The prevalence of adults aged 18+ who reported fair or poor health in 2020 in Mobile County, Alabama

C-10 Percentages of people that live in the floodplain in Mobile County, Alabama

C-11 Critical facilities in the 100-year floodplain in Mobile County, Alabama

C-12 Risk analysis and poverty in Mobile, Alabama

C-13 Environmental Justice Index for Mobile County, Alabama, compared to the state and nation

C-14 The Environmental Justice Index rank for Mobile County, Alabama

C-15 The 2020 national overall Social Vulnerability Index for Turkey Creek, Mississippi

C-16 The prevalence of adults aged 18+ who reported fair or poor health in 2020 in Harrison County, Mississippi

C-17 Percentages of people that live in the floodplain in Harrison County, Mississippi

C-18 Critical facilities in the 100-year floodplain in Harrison County, Mississippi

C-19 Critical facilities prone to flooding in Harrison County, Mississippi

C-20 People living below the poverty line in Harrison County, Mississippi

C-21 Environmental Justice Index for Harrison County, Mississippi, compared to the state and nation

C-22 The Environmental Justice Index rank for Harrison County, Mississippi

C-23 The 2020 national overall Social Vulnerability Index for Lafourche Parish, Louisiana

C-24 The 2020 national overall Social Vulnerability Index for Terrebonne Parish, Louisiana

C-25 The prevalence of adults aged 18+ who reported fair or poor health in 2020 in Lafourche and Terrebonne Parishes, Louisiana

C-26 Percentages of people that live in the floodplain in Lafourche Parish, Louisiana

C-27 Critical facilities in the 100-year floodplain in Lafourche Parish, Louisiana

C-28 Percentages of people that live in the floodplain in Terrebonne Parish, Louisiana

C-29 Critical facilities in the 100-year floodplain in Terrebonne Parish, Louisiana

C-30 Critical facilities prone to flooding in southeast Louisiana

C-31 People living below the poverty line in southeast Louisiana

C-32 Environmental Justice Index for Lafourche Parish, Louisiana, compared to the state and nation

C-33 Environmental Justice Index for Terrebonne Parish, Louisiana, compared to the state and nation

C-34 The Environmental Justice Index rank for Lafourche Parish (top) and Terrebonne Parish (bottom), Louisiana

C-35 The 2020 national overall Social Vulnerability Index for Jefferson County, Texas

C-36 The prevalence of adults aged 18+ who reported fair or poor health in 2020 in Port Arthur, Texas

C-37 Population in Jefferson County, Texas, at risk from sea level rise

C-38 Natural landscapes exposed to inundation in Jefferson County, Texas

C-39 Critical facilities prone to flooding in Port Arthur, Texas

C-40 People living below the poverty line in Port Arthur, Texas

C-41 Environmental Justice Index for Port Arthur, Texas, compared to the state and nation

C-42 Flood risk and hazardous waste facilities/infrastructure in Port Arthur, Texas

C-43 The Environmental Justice Index rank for Jefferson County, Texas. Port Arthur has areas with moderate to high environmental justice indexes

E-1 Gulf Coast timeline

TABLES

2-1 Days Over 95F (Historic and Projected) Across the Gulf Coast

2-2 Gulf Coast State Homes at Risk of Chronic Inundation in the Next 30 Years (i.e., by 2045)

4-1 Enslaved Populations in Gulf States, 1860

5-1 2010 Population for Shoreline Counties Along the Gulf Coast and Percentage of Population Change Between 1970 and 2010

8-1 Poverty Rates of Coastal Resettlement Destinations within 75–100 Miles from the Coast of Alabama, Mississippi, and Louisiana, by County, 2020 National and State

C-1 Population Sociodemographics

C-2 Hurricanes Impacting St. Petersburg, Florida, That Led to Federal Disaster Declarations Since 2000

C-3 Hurricanes Impacting Mobile County, Alabama, That Led to Federal Disaster Declarations Since 2000

C-4 Hurricanes Impacting Harrison County, Mississippi, That Led to Federal Disaster Declarations Since 2000

C-5 Hurricanes Impacting Lafourche and Terrebonne Parishes, Louisiana, That Led to Federal Disaster Declarations Since 2000

C-6 Hurricanes Impacting Port Arthur, Texas, That Led to Federal Disaster Declarations Since 2000

Preface

With increasing numbers of climate-related disaster events in Gulf Coast states (232 events occurring between 1980 and 2023, with twice as many per year from 2018 to 2022 as in the previous years) and extraordinary human and capital impacts (deaths of 10,838 people and costs on average of 1 billion dollars per disaster from 1980 to July 11, 2023), the consideration of how to reduce such impacts must grapple with the question of whether and how to relocate people and assets out of harm’s way. Frequently termed “managed retreat,” the topic of relocation receives scant attention in post-disaster recovery, when building back is prioritized; even less attention in pre-disaster mitigation planning; and almost no attention from regional planning organizations. This is not surprising, as the nation currently lacks consistent policy or programmatic guidance to enable communities and their governing bodies to tackle the uncomfortable issue of retreating from the coasts.

Recognizing the need for guidance, the Gulf Research Program (GRP) of the National Academies of Sciences, Engineering, and Medicine empaneled a committee of experts to study the issue of managed retreat in the Gulf Coast. The committee approached the study by reviewing the history of the region, by examining the science that characterizes the region’s future and helps to explain its disaster record, and by considering the overall impact of chronic stressors on community well-being. This study offers new guidance meant to improve our understanding of the intersectionality of community well-being, planning processes, government policy, and implementation funding.

Managed retreat remains an emerging area of research with few practical examples to date. Of the examples that exist, many lack coordination, large-scale support, or buy-in from the community. Important to understanding this context, the task challenged the committee to tackle not only the issues surrounding managed retreat but also the very language of managed retreat. Through the study process, this term evolved to become “community-driven relocation.”

We appreciate the range of perspectives, the depth of knowledge, and the ongoing efforts of members of the committee whose constructive debates and meaningful challenges to the very systems propagating disadvantage and the public health construct of well-being broadened the process to one of recognizing the need for transformative relationships between disciplines as much as transformations in participatory planning, funding, and regional collaboration. Thank you to the members of the committee.

The National Academies hosted workshops with frontline community members and municipal leaders from each of the Gulf Coast states whose stories echoed so many others in telling of the types of chronic stress that stems from the repetitive experiences of such disasters. We are grateful to those who participated in the workshops, sharing their lived experiences and raising questions to help guide the committee in the consensus study. We also extend heartfelt thanks to all workshop participants. We encourage each of you to continue to share those stories as your powerful voices help others to better understand the essence of the challenge.

With such challenging topics and range of activities, the committee relied heavily on the expertise of the National Academies staff who guided the process according to the National Academies standards and offered resources throughout the study to help the committee better characterize the issues for various audiences. Thanks to the National Academies staff whose commitment to this study and whose patience enabled the committee to tackle such a complex issue.

Community-driven relocation across the Gulf Coast is difficult to envision, even as sea level rise and subsidence combine to make the Gulf one of the most vulnerable areas in the nation. We thank the GRP for investing in such a challenging topic and, in doing so, catalyzing discussions that may in turn reduce risks while encouraging new collaborations and offering hopeful futures.

We wish to express our deep appreciation to the members of the committee for their diligent and dedicated contributions to developing this report. The diverse expertise and experience offered by the members of the committee were indispensable to the formulation of the report.

Janice Barnes, Co-Chair
Tracie Sempier, Co-Chair
Committee on Managed Retreat in the U.S. Gulf Coast Region

Acronyms and Abbreviations