SAFETEA-LU amended Section 142 of the Internal Revenue Code to add highway and freight transfer facilities to the types of privately developed and operated projects for which private activity bonds (PAB) may be issued. This change allows private activity on these types of projects, including development, design, finance, construction, operation, and maintenance, while maintaining the tax-exempt status of the bonds. PABs are issued by a public, conduit issuer on behalf of a private entity. The private entity is the obligor on the PABs.
SAFETEA-LU originally limited the total amount of such bonds to $15 billion. The 2021 Bipartisan Infrastructure Law increased the volume cap to $30 billion. The $30 billion in exempt facility bonds is not subject to state volume caps, the maximum amount of tax-exempt PABs that may be used in a state in a given year.
PAB allocation is managed by the U.S. Department of Transportation Build America Bureau, which maintains information on allocations to date, applying for an allocations, and process.