Office of Naval Research - National Transportation Library

Rivers have restricted throughput for some of the facilities. Because of these infrastructureconstraints, the types of vessels used to carry cargo on these waterways have effectively beenrestricted to tugs and barges. 9 Because barges have traditionally carried low-value goods atlow speeds, the conventional expectations of the SSS growth potential in the U.S. have beenfor a low-growth scenario.Compared to over-the-road truck transportation, water transportation carriers receive only afraction of the total domestic freight revenues, less than 2 percent of the value of thedomestic freight carried in the lower 48 states. By tonnage, however, domestic waterborneshipping account for larger shares of the national cargo volume, depending on how the sharesare calculated. The data indicate the following distribution of freight shipments by value,tonnage, and ton miles for domestic shallow water and deep-water facilities. 10Table 1 – SSS Freight Traffic by Value, Tonnage, and Ton-milesMarine Facility Type Value (% U.S. CargoShipments)Tons (% U.S.Tonnage Carried)Ton Miles (% U.S.Ton Miles)Shallow Draft 0.7 3.9 6.7Great Lakes - 0.3 0.4Deep Draft 0.4 1.6 1.8Total Waterborne 1.1 5.8 9.0Source: Bureau of Transportation Statistics, U.S. DOT; the figures exclude wet bulk shipments and watertraffic on the nation’s inland waterways.The second factor contributing to the low levels of revenue generated in domestic waterbornemarkets is the continuing decline in the ton-miles or cargo carried on domestic waterways.As noted above in reference to the trends depicted in Figure 2, the tonnage carried on MTShas remained stable around 1 billion tons in the past decade; whereas the length of shipmentshas declined steadily. The average length of coastwise shipments declined from 1,496 milesin 1960 to 1,269 in 2004. Lower waterborne ton miles of freight not only reduce the level ofrevenues generated in the service, they also reduce the break-even distance at which domesticwater transport becomes a viable option. The total ton miles of domestic waterborne traffic(on coastal, Great Lakes, and inland waterways) declined from 873 billion ton-miles to 591billion ton-miles between 1986 and 2005 (Figure 3.)9 Of the 25,000 miles of navigable inland waterways and intra-coastal/coastal channels, 12,000 miles of thenavigable inland waterways capable of handling commercial traffic; there are over 1800 shallow waterterminals with channel depth of 14 feet or less (1,748 on the Mississippi River system, and 64 onColumbia/Snake River.)10 “Shipment Characteristics by Mode of Transport for the United States,” US Department of TransportationBureau of Transportation Statistics, available fromhttp://www.bts.gov/publications/commodity_flow_survey/2002/united_states/html/table_01_b.html.ONR SSS Final Report 12