Some 41 states are served by over 25,000 miles of navigable rivers and canals of which 12,000 miles are operated and maintained by the federal government as commercial waterways.

Commercial carriers pay a special user tax of 20 cents per gallon on fuel consumed while operating on these waters. These taxes are deposited in a trust fund in the U.S. Treasury to help finance future improvements.

Locks and dams are constructed on most waterways to overcome the natural fall of the river from its headwaters to its mouth. The "slack water" pools formed by these structures help ensure more dependable channel conditions. Like much of the nation’s infrastructure, the 235 locks operating on the waterways are aging and are becoming outmoded. The average age of all the locks now exceeds 50 years.

Water transportation is the most efficient, less expensive, and most environmentally safe means of shipping large volumes of bulk-type commodities or heavy products long distances.