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Methods for State DOTs to Reduce Greenhouse Gas Emissions from the Transportation Sector


Increasingly, State departments of transportation (DOTs) are being asked to reduce greenhouse gas GHG emissions actions from the transportation sector. These requests are coming from the public, state governments (e.g., Governors’ offices), and from Federal Highway Administration (FHWA) (e.g., new requirements for addressing GHG emissions in National Environmental Policy Act (NEPA), potential national GHG performance measures). However, many of the strategies available to reduce GHG emissions from transportation are not under State DOT control (such as vehicle fuel economy standards and low carbon fuel standards). Many states lack the tools to quantify GHG emissions and it is often unclear what specific actions DOTs can take to reduce GHG emissions and the cost and benefits of those actions.

The research will give State DOTs the tools to evaluate the cost-effectiveness of potential GHG reduction actions and allow them to make informed decisions about how to meet current and future state and federal GHG reduction goals, targets, and requirements. It will look beyond enterprise efforts related to state fleets and buildings to identify specific strategies that may include electric vehicle (EV) infrastructure, travel demand management, mode shift, vehicles miles of travel (VMT) reducing projects, or other efforts influenced by State DOTs.


This research would identify specific efforts and strategies to reduce transportation sector greenhouse gas (GHG) emissions that are within the State Departments of Transportation (DOT) control and provide methods for estimating and monitoring their benefits and costs.


The most urgent need for this information is to meet new requirements from FHWA to evaluate GHG emission in NEPA documents. FHWA does not require GHG reductions associated with this effort, but State DOTs expect other stakeholders to make this request. Another benefit is to support the increasing number of states with state GHG reduction goals that they are not on track to meet. Finally, FHWA recently proposed a GHG performance measure; setting reduction targets, and working to achieve them, will require all State DOTs to better understand which GHG mitigation options they can directly implement or affect.

Without this research, State DOTs will be less able to discuss the context of the GHG emission results now required in NEPA documents. Should FHWA finalize a GHG performance measure, without the information and tool from this research, states will face substantially more work and uncertainty in setting goals and making decisions on how to meet them. Finally, State DOTs will continue to build transportation projects, but without an improved understanding of how to reduce GHG emission through their projects and programs will miss opportunities for reductions and could even unknowingly take actions that are counterproductive.

Related Research:

A vast body of work around transportation and GHG emissions has been developed ranging from in-depth discussion of specific strategies, such as installing solar panels in the ROW, to integrating GHG mitigation into planning, and to understanding lifecycle emissions from construction practices. A variety of tools and methods have been developed to calculate emission reductions in the transportation sector, e.g., EERPAT, which evaluates a wide variety of policy options at the state or county level.

However, efforts to apply those results to specific transportation stakeholders, including State DOTs, are lacking. State DOTs need solid information about what they can do to reduce GHG emissions from the transportation sector.

This research will build upon the existing body of research by focusing the information to actions State DOTs can take to reduce emissions.


Potential Order of Work and Deliverables:

· State of the Practice – Identify current State DOT practices and existing tools and information

· Compare tools and strategies to reduce GHG from transportation compared to State DOTs authority

· Identify challenges (specific to State DOTs) for reducing transportation GHG emissions

· Create dynamic tool(s) to evaluate costs and benefits of various GHG reduction strategies pre- and post-implementation

· Train State DOT staff to use the product(s) (e.g., webinar)


Target audience: State DOT staff and their consultants

Key decision makers who can champion implementation of products: AASHTO Resilient and Sustainable Transportation subcommittee

AASHTO committees and others responsible for adoption: AASHTO Air Quality and Climate Change subcommittee, State DOT staff

Early adopters: Several states including CA, CO, MD, MN, OR, WA

*Barriers to adoption: *Will depend on research results and future political climate

Sponsoring Committee:AMS10, Air Quality and Greenhouse Gas Mitigation
Research Period:24 - 36 months
RNS Developer:Karin Landsberg, Washington State Department of Transportation
Source Info:Karin Landsberg
Senior Policy Specialist – Air Quality and Energy
Washington State Department of Transportation
(360) 705-7491

Tim Sexton, AICP, ENV SP
Construction and Operations Section Director
Minnesota Department of Transportation
(651) 366-3622

Noel Alcala, P.E.
Noise and Air Quality Coordinator
Ohio Department of Transportation
(614) 466-5222

Austina Casey
Environmental Policy Analyst
District Department of Transportation
(202) 671-0494

Natalie Liljenwall
Environmental Engineering Program Leader (Air, Noise and Energy)
Oregon Department of Transportation
(503) 986-3456

Dillon Miner
Climate Change Branch
Office: (916) 653-4287

Marilee Mortenson
Air Quality and Environmental Planning Branch Chief
California Department of Transportation
(916) 653-3758

Rose Waldman
Air Quality and Noise Specialist
Colorado Department of Transportation
(303) 757-9016
Date Posted:09/19/2016
Date Modified:09/28/2016
Index Terms:State departments of transportation, Greenhouse gases, Performance measurement, Cost effectiveness, Electric vehicles, Travel demand management, Mode choice,
Cosponsoring Committees: 
Planning and Forecasting
Transportation (General)

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