• Roads are eligible for federal-aid if they are classified as rural major or urban collector, or any arterial. These are also called federal-aid highways.
• Roads shown as thick, Blue, Purple, Red, Green, and Orange lines are federal-aid highways.
• Roads shown as thick, Yellow lines -- rural minor collectors -- are eligible for federal-aid per current federal law.
• Roads shown as thin, Black lines -- local roads -- are NOT eligible for federal-aid.
• Most federal aid funding for road improvements goes either to the NHS (National Highway System) or roads eligible for STP (the Surface Transportation Program). NHS roads can be seen on the NHS Maps website
• STP funds may be used on any federal-aid highway, following the project selection process established by federal legislation.

Program-specific information can be found on the Grant Program website