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Transportation Safety: Federal Highway Administration Should Conduct Research to Determine Best Practices in Permitting Oversize Vehicles

GAO-15-236 Published: Feb 26, 2015. Publicly Released: Feb 26, 2015.
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Highlights

What GAO Found

The Department of Transportation's (DOT) Federal Highway Administration (FHWA) has established some federal vehicle size and weight requirements and oversees some state activities. Based on current legislation, FHWA has established rules and regulations for vehicle width, truck trailer length, and vehicle weight standards for certain federal-aid highways aimed at protecting highways and bridges from damage while providing a safe and efficient highway network. FHWA does not, however, have the authority to establish a height requirement, a decision that goes back to the Interstate System's construction in the 1950's, when height clearances already varied from state to state. FHWA also oversees states' processes for enforcing these standards by reviewing states' documentation of enforcement operations. However, FHWA has more limited involvement in individual states' permitting processes and requirements, which the agency considers largely a state matter. For example, it does not provide technical assistance on permitting to states.

Federal Vehicle Size and Weight Standards

Federal Vehicle Size and Weight Standards

State laws and regulations set varying size and weight limits and permitting requirements for vehicles that exceed these limits and that operate on highways and bridges. Specifically, GAO found that the vehicle size and weight limits set by state laws and regulations vary by state, although they are within the parameters of federal requirements. For example, states' length standards vary between the minimum federal standard of 48 feet and 65 feet for a semitrailer. GAO also found that permitting practices for oversize vehicles often vary by state. In some cases, states follow similar practices; for example, most states make use of online permitting systems and escort vehicles that travel with an oversize or overweight vehicle. However, other permitting practices vary by state—such as states' use of automated routing systems to provide a route for oversize vehicles. A National Transportation Safety Board investigation reported that differences among states on the various aspects of truck permitting could be a safety concern. State officials GAO interviewed did not always agree on the benefits of the various permitting practices, and some spoke of the need for more information on this topic. While FHWA is (1) conducting some research on the potential effect of changes to truck size and weight limits and (2) working with the trucking industry to update a best practices guide on escort vehicle operations, it has not studied permitting best practices across states due to lack of authority over state permitting. In GAO's prior work on improving agency performance, GAO found that identifying best practices can help identify changes that might be needed to improve performance. By conducting this type of research, FHWA would be better positioned to help states make sound decisions to improve safety and protect infrastructure.

Why GAO Did This Study

In May 2013, a truck carrying an oversize load crashed into an interstate bridge in Washington state causing it to collapse. This crash raised issues about oversize vehicles and public safety. DOT develops regulations on vehicle size and weight, and states enforce these standards with some oversight from DOT. States also issue their own regulations on vehicle size and weight and issue permits for oversize and overweight vehicles.

The Joint Explanatory Statement of the Consolidated Appropriations Act for Fiscal Year 2014 required GAO to review the role of federal and state agencies in overseeing oversize vehicles. This report discusses (1) how DOT regulates and provides oversight of oversize vehicles and (2) how states regulate oversize vehicles.

GAO collected information from 50 states and the District of Columbia about their permitting practices; reviewed relevant federal legislation and DOT regulations and documents; and interviewed DOT and state officials from a non-generalizable sample of 10 states, chosen based on a variety of considerations, including geographic diversity and types of permitting requirements.

Recommendations

GAO recommends that DOT conduct a study on states' oversize- and overweight-permitting practices, including automated vehicle routing and escort driver certification, to identify areas of best practice and share the results with states. DOT agreed with GAO's recommendation and provided clarifying comments, which GAO incorporated.

Recommendations for Executive Action

Agency Affected Recommendation Status
Department of Transportation To improve stewardship over the nation's highways and bridges, the Secretary of Transportation should direct the FHWA Administrator to conduct a study on state oversize- and overweight-permitting practices, including automated vehicle routing and escort driver certification, to identify areas of best practice and share the results with states.
Closed – Implemented
In February 2015, GAO reported that the Federal Highway Administration has established some vehicle size and weight requirements. However, states develop their own size and weight limits to be enforced in their state (incorporating the federal requirements) and issue oversize and overweight permits for vehicles that exceed these limits and that operate on highways and bridges. GAO found that requirements and permitting practices for oversize vehicles vary by state, such as some states' use of automated routing systems to provide a route for oversize vehicles and most states make use of escort vehicles that travel with oversize or overweight vehicles, but state officials did not agree on the benefits of these various practices. State officials GAO interviewed spoke of the need for more information on different permitting practices and their resulting benefits would be helpful to them to determine ways their state practices could be improved. According to FHWA officials, although they collect limited information on state permitting practices, they do not have research or data that compare state permitting information or identify best practices due to lack of authority over state permitting. However, FHWA has authority to conduct transportation research, including research on issues with national implications that could lead to improvements in highway safety, and in the past has worked with the trucking industry and others to identify best practices for related issues such as escort vehicles. Therefore, GAO recommended that the Department of Transportation direct FHWA to conduct a study on state oversize- and overweight-permitting practices, including automated vehicles routing and escort driver certification, to identify areas of best practice and share the results with states. In 2018, GAO confirmed that FHWA completed a study on state oversize- and overweight-permitting practices to identify best practices. FHWA published the results of this study as a report, available on its website, shared the report with its Division Offices for dissemination to state transportation officials and the trucking industry, and shared the report with the American Association of State Highway and Transportation Officials. As a result of this study, states have information on the range of practices and best practices to assist states in making sound decisions on their oversize vehicle permitting, which ultimately can improve safety and protect infrastructure.

Full Report

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Topics

Federal aid for highwaysFederal aid for transportationFederal lawFederal legislationFederal regulationsHighway researchHighway safetyInterstate commercePublic roads or highwaysStandardsTrucking operations