The U.S. Marine Transportation System (MTS) is the primary system by which goods enter and leave the United States, enabling the uninterrupted flow of maritime commerce. During 2018, over 90 percent of U.S. imports and exports moved through ports, supporting $4.6 trillion of economic activity and generating 23.1 million jobs. Approximately 2.3 billion tons of domestic and foreign commerce are carried annually on the U.S. inland waterways. The MTS touches virtually every aspect of American life-from the clothes we wear, to the cars and trucks we drive, to the food we eat, to the oil and natural gas used to heat and cool our homes. It is vital to American prosperity.
The U.S. MTS encompasses a vast network of waterborne transportation along our Nation's coastlines, our inland river systems, and the Great Lakes. More international trade is carried via the MTS than any other mode of transportation, providing critical support to the entire U.S. economy. The MTS is commonly referred to as a "system of systems" because of the many components that combine to facilitate the water and land supply chains.
The U.S. MTS includes:
- 25,000 miles of navigable channels
- 95,000 miles of shoreline
- 237 waterway locks at 192 sites
- More than 3,700 marine terminals
- 154 shipyards
- Almost 13.1 million U.S. cruise passengers in 2018
- 45,000 aids to navigation
- 75,000 fishing vessels
- 1,400 designated intermodal connections
- 233 ferry operators providing service through 515 terminals
- 361 commercial ports