To amend title 23, United States Code, relating to establishment of the National Transportation System.

Amends Federal transportation law to establish a National Transportation System (NTS) that will move people and goods in a way that promotes mobility, economic productivity, congestion relief, energy conservation, and air quality improvement.

Directs the Secretary of Transportation to submit to the Congress the designation of the NTS. Prohibits proposed new routes or facilities that are in nonattainment areas for ozone or carbon monoxide, or segments of the National Highway System (NHS), from being included in the NTS until they have been included in a metropolitan or State long-range plan transportation improvement program conforming to a State implementation plan developed pursuant to the Clean Air Act. Authorizes the Secretary to make grants to pay 80 percent of the development and implementation costs of the NTS.

Requires a metropolitan or State long-range plan to identify, at a minimum, transportation facilities, including, among others, airport, port, inland waterway, and railroad, that function as an integrated metropolitan or State transportation system, giving emphasis to facilities that serve important national and regional transportation functions. Requires such transportation systems to serve as the NTS in such metropolitan area or State, unless the Secretary determines it would not be in the public interest or promote the goals of the NTS. Directs the Secretary to set-aside a specified percentage of NHS funds for grants for the developmental costs of the NTS.

Directs States to set-aside a specified percentage of their NHS apportionment to provide intermodal connections to the NHS or connections between the NHS and the NTS. Prohibits the use of State set-asides for projects that add new capacity for single-occupant passenger vehicles (other than for facilities which are part of a system that reduces their use). Sets forth formulae for the apportionment of NHS funds to certain urbanized and rural areas.