Highways
Infrastructure Act Spending Could Impact Emissions Reduction Efforts, Analysis Says
Georgetown Climate Center study projects carbon dioxide emissions will drop over 10 years
Researchers say building new highways with infrastructure package funds may slow efforts to reduce carbon emissions, while focusing the money on maintenance and lower-carbon strategies could cut emissions faster.
Photo courtesy of North Dakota Dept. of Transportation
How new Infrastructure Investment and Jobs Act funding is spent could lower greenhouse gas emissions—but also boost them, Georgetown University researchers say.
In an analysis of the just enacted infrastructure package, the Georgetown Climate Center, part of the Washington, D.C., school's Law Center, assessed possible effects of the $599-billion chunk of the law's total $1-trillion that is estimated to be allocated for surface transportation. Researchers contend that the selection of projects to be funded has the potential to either hasten an expected decline in GHG emissions or slow efforts to cut them.
The analysis uses a baseline transportation emissions scenario that projects a decrease in GHG emissions over the next decade and settled on two scenarios designed to show the highest and lowest potential emissions impacts related to infrastructure package surface transportation projects. The baseline is projected to decrease from more than 1.35-billion metric tons of transportation-related carbon dioxide emissions in 2022 to about 1.13-billion metric tons by 2032.
The high-emission scenario projects 1.6% more emissions in 2032, while the low-emission scenario projects 1.3% less than the baseline.
“Where the actual outcome falls within that range will depend on the decisions made by state, federal and local governments about how to spend the money made available by IIJA,” the researchers wrote in a summary of their findings.
Highway spending in particular may swing the infrastructure package’s impact one way or the other. The high-emission scenario assumes that 27% of the money would support highway expansion and 23% spent on existing highway maintenance. The low-emission scenario drops the amount spent on new highways to just 4% and allocates 38% toward maintenance. That scenario also reflects other low-carbon strategies, with greater portions of the money allocated tor infrastructure for pedestrians, cyclists and electric vehicles. The researchers wrote that they expect reality to fall somewhere between the two scenarios.
While it will take time for most projects funded by the infrastructure act to get underway, some transportation officials already are taking steps to make them more sustainable and resilient.
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The Federal Highway Administration released guidance on Dec. 16 that encourages state and local agencies to prioritize maintenance and modernize existing transportation infrastructure—rather than build new roads.
Several state transportation departments also have moved to reduce highway project GHG emissions.
In Colorado, officials recently approved a new rule to move money to more environmentally friendly projects by requiring GHG emissions estimates in planning, setting emission reduction levels and restricting funds from projects that don’t mitigate emissions.
“What all this will likely mean in practice is greater investments in projects that improve quality of life and air quality for Coloradans, such as adding sidewalks and protected bike facilities, improving local and intercity transit and supporting compact and walkable land use,” Kelly Blynn, transportation climate change specialist for the Colorado Energy Office, wrote in a blog post about the rule.
State transportation departments and local planning organizations will be key to choosing projects funded by the infrastructure act and ensuring they are executed in a climate-conscious way, the Georgetown researchers wrote.
State governments also will be able to help shape federal regulations, such as the Federal Highway Administration’s GHG emissions performance measure, they added.
