 As the state is bounded by two of the largest rivers in North America, water transportation has historically played a major role in Kentucky's economy.Louisville was a major port for steamships in the nineteenth century.Today, most barge traffic on Kentucky waterways consists of coal that is shipped from both the Eastern and Western Coalfields, about half of which is used locally to power many power plants located directly off the Ohio River, with the rest being exported to other countries, most notably Japan.