Inland waterways transportation
The movement of cargo on inland and intracoastal waterways by barge. About 14% of the bulk movement of commerce in the United States moves by barge, amounting to over 6 × 108 tons (5.4× 108 metric tons) annually. Barges directly serve 87% of all major United States cities, accounting for 65% of all domestic waterborne traffic.
Barges move on the 25,543-mi (41,107-km) network of commercially navigable inland and intracoastal waterways. Generally, barges are either pushed or towed by towboats on the inland waters. Barges require standard operating depths of at least 9 ft (about 3 m). Certain sections of the inland waterways are deep enough to support ocean-going vessels, including the Hudson River to Albany, New York, the Lower Mississippi north to Baton Rouge, Louisiana, the Houston Ship Channel, the Delaware River, the James River, and portions of the Columbia-Snake River.
Three major types of barges are used on the inland and intracoastal waterways: the open hopper, the covered dry cargo, and the tank barge. The open hopper barge is used to transport cargo that does not need to be protected from the elements, such as coal, sand, and gravel. Cargoes that need protection, such as grain, are shipped on covered dry cargo barges. Tank barges carry liquid commodities, such as petroleum and chemicals.
Towboats with barge flotillas commonly operate on the inland waterways, where they are fully protected by land on either side. The barges are kept together by wire rigging and are lashed against the towing knees of the towboat which pushes them ahead. On open channels, such as the Atlantic and Gulf intracoastal waterways, tugboats are used, which pull barges on a hawser.
With the exception of the New York State Barge Canal, which is state-run, the inland waterways of the United States are maintained on a federal level by the Army Corps of Engineers. Since 1980, barge operators have paid a fuel tax that pays for a percentage of the construction, operation, and maintenance costs for inland waterway projects. Before this time, all projects were entirely federally funded with appropriations from Congress.
