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Highway Funding: Information on Variables for Potential New Formula Grant Programs

Government Accountability Office
05/06/2025


Fast Facts

Each year, the Department of Transportation distributes billions of dollars to Tribes, states, and localities to build and repair road infrastructure. Most of these funds are distributed by formula grant programs, which use variables to calculate how much money recipients receive.

As Congress develops new surface transportation legislation, it could create new formula programs. We surveyed current recipients and others, who suggested multiple variables that Congress could consider using to distribute funding in potential formula programs.

These variables included bridge condition, vehicle miles traveled, and road fatality rates.

Highlights

What GAO Found

Each year, the federal government distributes billions in funding through federal highway formula grant programs (commonly referred to as formula programs) to Tribes and states to build highway infrastructure and for other purposes. These grants are distributed to recipients using statutory formulas and may be used to build and repair infrastructure and facilitate the movement of people and goods. GAO interviewed 31 selected highway program funding recipients, subrecipients, and stakeholders and then surveyed them to gauge their level of support for variables that could be used in formulas to distribute funding through potential new highway formula programs.

Most of the 28 survey respondents supported 27 variables that could be used to distribute funding for potential new programs. Almost all the supported variables related to infrastructure condition, freight movement and economic vitality, safety, and system reliability. Specifically, respondents supported variables such as total lane miles, vehicle miles traveled, and bridge condition. While selected funding recipients, subrecipients, and stakeholders identified and rated variables that could be used, they generally did not support creating new federal highway formula programs.

GAO found that federal data sources are available and can be used to measure 22 of the 27 supported variables. Most of the data are maintained by the Department of Transportation, primarily as part of its Transportation Performance Management program and the annual Highway Statistics Series. Of the five supported variables for which GAO did not identify a federal data source, agency officials noted privacy concerns or no requirement to collect such data, among other reasons for not collecting the data.

Why GAO Did This Study

The Infrastructure Investment and Jobs Act authorized and appropriated over $300 billion in funding for highway formula programs for fiscal years 2022 through 2026. As Congress deliberates about what to include in the next surface transportation authorization, it may create new formula programs, which it has done in some prior surface transportation authorizations.

GAO was asked about variables that could be used for potential new federal highway formula programs. This report describes: (1) the views of selected stakeholders with expertise and federal highway funding recipients on variables that could be used for potential new federal highway formula programs and (2) federal data that could measure these variables.

GAO reviewed applicable federal statutes and regulations, notices, and fact sheets to understand which variables are used to distribute funding under current highway formula programs. GAO used interviews and a survey to elicit views from selected federal highway funding recipients, subrecipients, and stakeholders. Specifically, GAO asked 31 interviewees to identify variables that could be used in formulas for potential new federal highway programs, and then surveyed them, receiving responses from 28 on their support for 96 suggested variables. GAO selected a non-generalizable mix of funding recipients, such as Tribes and state departments of transportation, based on their location. GAO also reviewed federal datasets and interviewed relevant agency officials to determine the availability of federal data to measure variables identified by interviewees.

For more information, contact Elizabeth Repko at repkoe@gao.gov.

GAO Contacts

Elizabeth (Biza) Repko Director Physical Infrastructure repkoe@gao.gov

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Sarah Kaczmarek Managing Director Office of Public Affairs media@gao.gov

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Topics

TransportationPublic roads or highwaysFreightFederal-aid highway programBridgesGrant programsSet-asidesSurface transportationSafetyHighway safetyPerformance measurement