NCHRP
Web-Only Document 400
Considering Greenhouse Gas Emissions and
Climate Change in Environmental Reviews
CONDUCT OF RESEARCH REPORT
Cambridge Systematics, Inc.
Medford, MA
Georgetown Climate Center
Washington, DC
Parametrix
Seattle, WA
Inch and Meter
Philadelphia, PA
Zamurs and Associates, LLC
Slingerlands, NY
Conduct of Research Report for NCHRP Project 25-64
Submitted January 2024
© 2024 by the National Academy of Sciences. National Academies of Sciences, Engineering, and Medicine and the graphical logo are trademarks of the National Academy of Sciences. All rights reserved.
Digital Object Identifier: https://doi.org/10.17226/27888
NATIONAL COOPERATIVE HIGHWAY RESEARCH PROGRAM
Systematic, well-designed, and implementable research is the most effective way to solve many problems facing state departments of transportation (DOTs) administrators and engineers. Often, highway problems are of local or regional interest and can best be studied by state DOTs individually or in cooperation with their state universities and others. However, the accelerating growth of highway transportation results in increasingly complex problems of wide interest to highway authorities. These problems are best studied through a coordinated program of cooperative research.
Recognizing this need, the leadership of the American Association of State Highway and Transportation Officials (AASHTO) in 1962 initiated an objective national highway research program using modern scientific techniques—the National Cooperative Highway Research Program (NCHRP). NCHRP is supported on a continuing basis by funds from participating member states of AASHTO and receives the full cooperation and support of the Federal Highway Administration (FHWA), United States Department of Transportation, under Agreement No. 693JJ31950003.
COPYRIGHT INFORMATION
Authors herein are responsible for the authenticity of their materials and for obtaining written permissions from publishers or persons who own the copyright to any previously published or copyrighted material used herein.
Cooperative Research Programs (CRP) grants permission to reproduce material in this publication for classroom and not-for-profit purposes. Permission is given with the understanding that none of the material will be used to imply TRB, AASHTO, APTA, FAA, FHWA, FTA, GHSA, or NHTSA endorsement of a particular product, method, or practice. It is expected that those reproducing the material in this document for educational and not-for-profit uses will give appropriate acknowledgment of the source of any reprinted or reproduced material. For other uses of the material, request permission from CRP.
DISCLAIMER
The opinions and conclusions expressed or implied in this report are those of the researchers who performed the research. They are not necessarily those of the Transportation Research Board; the National Academies of Sciences, Engineering, and Medicine; the FHWA; or the program sponsors.
The Transportation Research Board does not develop, issue, or publish standards or specifications. The Transportation Research Board manages applied research projects which provide the scientific foundation that may be used by Transportation Research Board sponsors, industry associations, or other organizations as the basis for revised practices, procedures, or specifications.
The Transportation Research Board, the National Academies, and the sponsors of the National Cooperative Highway Research Program do not endorse products or manufacturers. Trade or manufacturers’ names appear herein solely because they are considered essential to the object of the report.
The information contained in this document was taken directly from the submission of the author(s). This material has not been edited by TRB.
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.
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Learn more about the Transportation Research Board at www.TRB.org.
COOPERATIVE RESEARCH PROGRAMS
CRP STAFF FOR NCHRP WEB-ONLY DOCUMENT 400
Waseem Dekelbab, Deputy Director, Cooperative Research Programs, and Manager, National Cooperative Highway Research Program
Michael Brooks, Senior Program Officer
Demisha Williams, Senior Program Assistant
Natalie Barnes, Director of Publications
Heather DiAngelis, Associate Director of Publications
Jennifer J. Weeks, Publishing Projects Manager
NCHRP PROJECT 25-64 PANEL
Field of Transportation Planning—Area of Human and Natural Environment
Bradley M. Sharlow, Michigan Department of Transportation, Lansing, MI (Chair)
Joshua S. Fu, University of Tennessee, Knoxville, Knoxville, TN
John Jamison, North Carolina Department of Transportation, Raleigh, NC
Taylor LaBrecque, Maine Department of Transportation, Augusta, ME
Sharon Natalie Liljenwall, Oregon Department of Transportation, Salem, OR
Jackie A. Ploch, Texas Department of Transportation, Austin, TX
Stacy DeGabriele Williams, TRC, Boston, MA
Rebecca K. Lupes, FHWA Liaison
Christine L. Gerencher, TRB Liaison
AUTHOR ACKNOWLEDGMENTS
The research reported herein was performed under National Cooperative Highway Research Program (NCHRP) Project 25-64 by Cambridge Systematics, Inc.; the Georgetown Climate Center; Parametrix; Inch and Meter; and Zamurs and Associates, LLC. Chris Porter of Cambridge Systematics was the Principal Investigator. Joshua Proudfoot of Parametrix, Annie Bennett and Katie Spidalieri of Georgetown Climate Center, Jelena Matic of Inch and Meter, and John Zamurs of Zamurs and Associates, LLC were the principal subject matter contributors from the project team. Additional research support was provided by Adrienne Heller and Benjamin Eskin of Cambridge Systematics and by Nicole Somers of Inch and Meter and Aaron Toneys of Parametrix. Advisory consulting services were provided by Samuel Jordan (Baltimore Transit Equity Coalition), Thomas LeFebvre (Center for Latino Progress/Transport Hartford), and Harrison Humphreys (Air Alliance Houston).
The project team also acknowledges the assistance of State DOT staff who served as lead points of contact for the pilot application of the guide. These included Theresa Takushi and Matt Muraro (Colorado DOT) and Nastasha Earle-Young (North Carolina DOT).
TABLE OF CONTENTS
Suggestions for Additional Research
CHAPTER 3: Review of Current Practice, Methods, and Tools
CHAPTER 4: Outreach and Implementation Activities
DOT Surveys, Interviews, and Peer Exchanges
NGO/CBO Surveys, Interviews, and Workshop
How the Outreach Informed the Guide
CHAPTER 5: Additional Research
APPENDIX A: State DOT Survey Instrument
APPENDIX B: State DOT Survey Responses
APPENDIX C: State DOT Interview Questions
APPENDIX D: NGO-CBO Survey Instrument
NCHRP Web-Only Document 400 contains the Conduct of Research Report for NCHRP Project 25-64 and accompanies NCHRP WebResource 3: GHG Emissions and Climate Change in Environmental Reviews. Readers can find NCHRP WebResource 3 at crp.trb.org/nchrpwebresource3/.
