Transportation for America Uses Artificial Intelligence to Analyze IIJA Spending

Greensboro Metro Station with cars to the left on Route 7 and a 7000-series train on the rails by Kyle Anderson licensed under Creative Commons.

The transportation sector is the largest emitter of greenhouse gases (GHGs) in the United States, producing 29 percent of total U.S. GHG emissions. Federal policy plays an outsize role in funding the highways and related road infrastructure that directly enables transportation emissions. In 2021, the government doubled down on that federal impact: the Infrastructure Investment and Jobs Act (IIJA) injected $600 billion into federal highway and public transportation projects.

To assess how states are spending IIJA funds, Transportation for America (T4A), a Summit grantee, conducted an AI-assisted review of over 57,000 IIJA-funded project descriptions. T4A’s analysis comes as experts have found that the lack of guardrails on the IIJA means that what was initially touted as a climate-friendly bill might end up increasing emissions overall. Those concerns are well-founded: T4A’s research shows that, by 2040, the IIJA is likely to produce 69 million more tons of carbon emissions than would otherwise have been created had the legislation not been enacted. This is because state Departments of Transportation (DOTs), which have wide latitude in deciding how to use federal funds, are using IIJA dollars to expand highways and roads, which increases carbon emissions by encouraging more car travel and associated congestion.

Early in IIJA’s authorization period, legal experts determined that up to 50 percent of IIJA highway formula funds can be flexed for transit and multimodal projects. However, T4A’s report determined that over a quarter of the law’s formula dollars—$33.5 billion, to be more exact—are being used to finance road capacity expansion projects that will drastically increase emissions. Moreover, their research indicates that state DOTs have been comparatively slow to allocate funds for transit and other emissions-reducing projects.


T4A’s analysis of IIJA spending illustrates the challenges in current IIJA deployment but also makes clear what state DOTs need to do to right the course. Fortunately, Transportation for America is among a larger group of electrification and multimodal transportation advocates who are unifying around a demand that state DOTs use IIJA funds to chart a path forward that addresses climate, equity, and economic opportunity through smarter transportation investments. If their efforts succeed, state Departments of Transportation could go from being some of the biggest contributors to greenhouse gases to leaders in the fight against pollution and climate change.


The IIJA is a climate time bomb. Will states defuse it?  – Transportation for America

At its two-year anniversary, the bipartisan infrastructure law continues to rebuild all of America – The Brookings Institution

Issue Brief: Estimating the Greenhouse Gas Impact of Federal Infrastructure Investments in the IIJA – Georgetown Climate Center

Issue Brief: Flexible Federal Funding Opportunities for State and Local Clean Transportation Investments – Georgetown Climate Center

The Congestion Con – Transportation for America

Transportation GHG Emissions  – U.S. Environmental Protection Agency

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