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Atlanta Regional Commission Reduces Regional Greenhouse Gas Emissions through Performance-Based Transportation Project Selection
OVERVIEW
The Atlanta Regional Commission (ARC) incorporates greenhouse gas (GHG) emissions as a scoring criterion for its regional transportation project selection process to promote investments in sustainability and performance-based planning decisions.
BACKGROUND
ARC is the metropolitan
Score Criteria Components
planning organization (MPO) Mobility &
Evaluates whether the project relieves
for the 20-county Atlanta,
Access
congestion, how many people it serves, can
Georgia region and has been
efficiently improve travel times and reliability,
an active advocate for
and connects people to destinations.
reducing GHG emissions in
Equity
Evaluates if the project serves underserved
the area. ARC has developed
populations based on where the project
a multi-faceted scoring
physically is located, who the project services,
system for quantifying the emissions associated with transportation projects. This approach allows ARC to demonstrate its progress toward State performance measures, while also working towards its own regional goals for improving access, mobility, connectivity, and air quality. ARC has shown
Safety Resiliency
and the kinds of outreach the sponsor has conducted. Evaluates if the addition of this project addresses the transportation safety issues present in the project area. Evaluates how much the project will reduce emissions, greenhouse gases, and if it addresses stormwater management issues present in the project area.
Table 1: TIP Key Scoring Criteria
leadership in climate action in the absence of state-level goals and guidance on GHG emissions
reductions. With a grant from the Environmental Protection Agency, Georgia is developing their first
ever Climate Action Plan, which will influence ARC's future approach and investments towards emissions
reductions. The document will serve as roadmap for how the state will manage the effect of climate
change and reduce statewide GHG emissions. Initial drafts are expected to be available by early 2024.
INTEGRATION WITH TRANSPORTATION PLANNING
ARC's latest metropolitan transportation plan (MTP), Atlanta Region's Plan, emphasizes sustainability and includes strategies to reduce GHG emissions. The MTP guides transportation investments and policies in the Atlanta region through 2050. ARC also includes GHG reduction as a scoring criterion for project selection and programming.
To guide project selection and prioritization for its Transportation Improvement Program (TIP), ARC created the ARC TIP Project Evaluation Framework, also known as the "The Project Evaluation Cookbook" or "TIP Cookbook." The framework outlines scoring criteria, measures, and metrics and demonstrates how they apply to different project types. Each criterion includes a combination of quantitative and qualitative analysis elements.
First, ARC planners filter projects that do not align with regional policy and goals through normalized scoring across projects of similar types. ARC uses nine general project types, each of which is subject to four primary scoring criteria: Mobility and Access, Equity, Safety, and Resiliency (Table 1). These four categories parallel Federal transportation priorities.
The Resiliency category includes air quality and emissions considerations, in addition to how projects will impact natural disasters resiliency and hazard mitigation. The specific formula varies by project type, but GHG reduction typically comprises 25 percent of the air quality score, which is typically 70 percent of the full Resiliency score. Resiliency comprises between 15 and 20 percent of the total project score, depending on project type, therefore GHG reduction typically comprises between three and five percent of the final project score.
After the score is tallied for a project within its project category, ARC staff then weigh projects across the entire potential portfolio and the transportation goals for the region. The project evaluation framework also assesses project proposals for their project deliverability, benefit-cost ratio, and costeffectiveness.
Measure
Metric
Nature of Metric Sponsor Provided
Percent of Criterion Score
Changes in NOx
Numerical; in
Yes
25%
emissions
kg/year
Changes in VOC
Numerical; in
Yes
25%
emissions
kg/year
Project Emissions Changes in PM2.5 Numerical; in
Yes
25%
emissions
kg/year
Change in
Numerical; in
greenhouse gas
kg/year
Yes
25%
emissions CO2(e)
Table 2: Metrics for Evaluating the Bicycle & Pedestrian Air Quality & Climate Change Criterion
Source: ARC TIP Cookbook 2021
or use of similar Excel-based calculators will be considered for project evaluation based on their ability to reliably predict emissions impacts of individual or packages of projects.
The TIP Cookbook is continually undergoing evaluation and improvement to better guide the region toward reducing GHG emissions, and ultimately, an improved transportation network. ARC is also considering opportunities to incorporate more emphasis on housing and land use considerations into its transportation planning processes.