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| This article is part of a series on the |
| Economy of the United States |
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The vast majority of passenger travel in the United States occurs by automobile for shorter distances and airplane or railroad for longer distances. Most cargo in the U.S. is transported by, in descending order, railroad, truck, pipeline, or boat; air shipping is typically used only for perishables and premium express shipments. Transportation is the largest source of greenhouse gas emissions in the United States.
Ownership and jurisdiction
The overwhelming majority of roads in the United States are owned and maintained by state and local governments. Federally maintained roads are generally found only on federal lands (such as national parks) and at federal facilities (like military bases). The Interstate Highway System is partly funded by the federal government but owned and maintained by individual state governments. There are a few private highways in the United States, which use tolls to pay for construction and maintenance. There are many local private roads, generally serving remote or insular residences.
Passenger and freight rail systems, bus systems, water ferries, and dams may be under either public or private ownership and operation. Civilian airlines are all privately owned. Most airports are owned and operated by local government authorities, but there are also some private airports. The Transportation Security Administration has provided security at most major airports since 2001.
The U.S. Department of Transportation and its divisions provide regulation, supervision, and funding for all aspects of transportation, except for customs, immigration, and security, which are the responsibility of the U.S. Department of Homeland Security. Each state has its own Department of Transportation, which builds and maintains state highways, and depending upon the state, may either directly operate or supervise other modes of transportation.
Aviation law is almost entirely the jurisdiction of the U.S. federal government, and automobile traffic laws are enacted and enforced by state and local authorities except on highways or roads on federal property or in unorganized territories. Economic jurisdiction over tidelands is shared between the state and federal governments, while the United States Coast Guard is the primary enforcer of law and security on U.S. waterways.
Passenger
| Mode of passenger transport | Passenger-miles (millions) |
Percent |
|---|---|---|
| Highway — total | 4,273,876 | 86.93% |
| Passenger vehicles, motorcycles | 3,692,760 | 75.11% |
| Trucks | 268,318 | 5.46% |
| Buses | 312,797 | 6.36% |
| Air Carriers | 580,501 | 11.81% |
| Rail — total | 37,757 | 0.77% |
| Transit | 19,832 | 0.40% |
| Commuter | 11,121 | 0.23% |
| Intercity/Amtrak | 6,804 | 0.14% |
| All other modes (e.g., ferryboats) | 4,156 | 0.08% |
| Source: 2012 estimates by the Bureau of Transportation Statistics[1] | ||
Passenger transportation is dominated by a network of over 3.9 million miles of highways[2] which is pervasive and highly developed by global standards. Passenger transportation is dominated by passenger vehicles (including cars, trucks, vans, and motorcycles), which account for 86% of passenger-miles traveled. The remaining 14% was handled by planes, trains, and buses.[3][4] Public transit use is highly concentrated in large older cities, with only six above 25% and only New York City above 50% of trips on transit. Airlines carry almost all non-commuter intercity traffic, except the Northeast Corridor where Amtrak carries more than all airlines combined.
The world's second largest automobile market,[5] the United States has the highest rate of per-capita vehicle ownership in the world, with 865 vehicles per 1,000 Americans.[6]
Bicycle usage is minimal with the American Community Survey reporting that bicycle commuting had a 0.61% mode share in 2012 (representing 856,000 American workers nationwide).[7][8]