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EM - Advancing Methods to Evaluate Greenhouse Gas Emissions During Transportation Decision Making and Performance Management

Funding

$300,000

Research Period

24 months

Background Information

State DOTs have access to a growing number of tools that may allow them to evaluate GHG emissions impacts. However, research is needed to understand how such tools can best be incorporated into transportation decision making processes and what additional tools may be necessary.

Existing tools for transportation GHG strategy analysis have not been developed with transportation programming and project prioritization in mind. The available tools are either designed for strategic level evaluation of policies (e.g., EERPAT, VisionEval) or project-level evaluation using data more detailed than is typically available during planning and programming (e.g., FHWA CMAQ Emissions Calculator Toolkit, California Life-Cycle Benefit/Cost Analysis Model or Cal-B/C). Other common tools for transportation evaluation, including statewide and regional travel demand models and emission factor models such as MOVES, are limited in their ability to evaluate GHG reduction strategies and typically require substantial modification and/or combination with other tools and methods.


Literature Search Summary

Existing literature describing transportation GHG evaluation tools and their application for planning and programming includes:
● NCHRP WebResource 1, Reducing Greenhouse Gas Emissions: A Guide for State DOTs (2022).
● Oregon Department of Transportation (2018), Oregon Greenhouse Gas Modeling and Analysis Tools.
● FHWA, Handbook for Estimating Transportation Greenhouse Gases for Integration into the Planning Process (2013).
● NCHRP Web-Only Document 152, Assessing Mechanisms for Integrating Transportation-Related Greenhouse Gas Reduction Objectives into Transportation Decision Making (2010).
Additional literature addresses consideration of air quality issues in programming, with lessons that could potentially applied to GHG consideration:
● Rowangould, G., Nadafianshahamabadi, R., & Poorfakhraei, A. (2018). Programming Flexible Congestion Mitigation and Air Quality Program Funds: Best Practices for State DOTs. Transportation Research Record, 2672(51), 99–108.
Other relevant research in progress includes:
● NCHRP Project 20-05, Topic 54-21, Synthesis of Information Related to Highway Practices: Practices in the Transportation Planning Process to Address Climate Resilience and GHG Emission Quantification and Reduction.
● NCHRP 08-154, Guidance for Agencies to Incorporate Uncertainty into Long-Range Transportation Planning.
● NCHRP Project 25-70, Developing a Framework for Evaluation of Decarbonization Outcomes.


Objectives

The objective of this research is to advance the practice of incorporating greenhouse gas (GHG) emissions evaluation into transportation decision making and performance management. In particular, this will be accomplished by identifying and building upon the state of the practice for state departments of transportation (DOTs) with regard to accounting for transportation related GHG emissions during planning, project prioritization, and performance management. State DOTs have access to certain tools that allow for estimation and evaluation of transportation emissions, but additional tools and methods are needed to inform decision making and align with state and federal GHG emission-reduction goals.

The following research tasks will support the main objective:
Task 1: Review literature and conduct targeted outreach to state DOTs to identify existing methods and tools used to evaluate potential GHG outcomes during transportation decision making processes. For each specific policy making process, describe how available tools, data and information support decision making within that context.
Task 2: Analyze the results of the review/survey to identify gaps where existing tools are not adequate to inform transportation decision making.
Task 3: Develop an analytical basis to fill identified gaps and propose specific additional tools, analytical methods and other information that would be needed to meet the needs of state DOT more fully, aiming to account for the GHG performance of transportation projects during planning, project prioritization and performance management activities


Keywords/Terms

greenhouse gas; performance management


Link to 2021-2026 AASHTO Strategic Plan

This project is aligned with the AASHTO Vision to provide improved quality of life through leadership in transportation. The project would advance goals identified in the AASHTO Strategic Plan, including improving asset performance and evaluating emerging trends in technologies, policies and practices. This project would also support a number of strategies in the Strategic Plan, including establishing frameworks and tools to enable impactful policy decisions, supporting implementation within member agencies, advocating to minimize the impacts of climate change, and applying scenario planning to better weigh options in decision-making.


Urgency and Potential Benefits

Transportation is the largest source of GHG emissions in most U.S. states. As states seek to achieve emissions reductions from the transportation sector, either on their own or to comply with federal regulations, it will be necessary for state DOTs to evaluate the GHG emissions impacts of investment decisions and align future projects and plans with GHG targets. Widely available reliable tools to evaluate GHG emissions will be needed at various stages of state DOT transportation decision making processes, from long-range planning to performance evaluation.

New federal and state requirements increasingly tie GHG evaluation to transportation decision making. The Carbon Reduction Program, established under the Bipartisan Infrastructure Law (December 2021), requires state DOTs and MPOs to develop carbon reduction strategies to support the reduction of transportation emissions. FHWA’s proposed GHG Transportation Performance Management measure would require state DOTs and MPOs to establish and meet declining targets for transportation emissions on the National Highway System. In addition, a growing number of states (including Colorado and Minnesota) have adopted planning standards that require DOTs and MPOs to evaluate the GHG impacts of transportation projects.


Implementation Considerations

State DOT staff, especially those responsible for planning, project prioritization, and performance evaluation, will be engaged to identify current practices and opportunities to incorporate GHG evaluation tools and methods into transportation decision making. DOTs may need to work with partners to inform the development of additional tools based on gaps identified through this research.

There are several other AASHTO and TRB committees interested in greenhouse gas emissions that would likely support this project, including:
• AASHTO:
o Committee on Performance Based Management (CPBM) Task Force on Emerging Performance Measures - Deanna Belden, Minnesota DOT and Kelly Travelbee, Michigan DOT, Co-Chairs
o Committee on Environment and Sustainability
o Committee on Planning
• TRB:
o Performance Management (AJE20) - Michael Grant, Chair
o Air Quality and Greenhouse Gas Mitigation (AMS10)
o Transportation Planning Policy and Processes (AEP10)
o Transportation Planning Analysis and Application (AEP15)
o Environmental Analysis and Ecology (AEP70)

a. Communication and Implementation Funding: [to be completed]
b. Communication and Implementation Period: [to be completed]


Author(s)


Others Supporting Problem Statement

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Person Submitting Statement

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Notes

10. PROBLEM STATEMENT AUTHOR(s): For each author, provide their name, affiliation, email address and phone.
James Bradbury, Georgetown Climate Center, [email protected], (202) 557-6267
Ryan Levandowski, Georgetown Climate Center, [email protected], (802) 558-3566
Kelly Travelbee, Michigan DOT, [email protected], (517) 898-4875
Deanna Belden, Minnesota DOT, [email protected], (651) 366-3734