Planning Center of Expertise for Inland Navigation (PCXIN) Outreach

Published Jan. 18, 2024


State Profiles
State Profiles
Planning Center of Expertise for Inland Navigation (PCXIN) State Profiles
Photo By: Huntington District
VIRIN: 240319-A-A1409-001

This site provides information on Waterborne Commerce in the United States, with a focus on the Inland Navigation data.

Navigation was the Corps of Engineers' earliest Civil Works mission, dating to Federal laws in the 1820’s authorizing and funding the Corps to improve safety on the Ohio and Mississippi Rivers by removing snags, debris, and other obstructions. These rivers and the coastal ports were the primary routes of commerce for the new nation.

This authorization set the nation on a course for the next two centuries of dredging channels, building locks and dams, wing dikes and other structures to create an inland waterways transportation system for the movement of goods on the nation’s rivers. The system includes rivers such as the Mississippi, Missouri, Ohio, Illinois, Columbia, Tennessee, Arkansas, Monongahela and Kanawha. Other smaller rivers are also included along with the Gulf Intracoastal Waterway (GIWW).

Today the inland waterway transportation system provides an important alternative to truck and rail. It is a highly cost-effective and energy efficient means for transporting commercial goods, especially major bulk commodities like coal, grain, and petroleum products. This system is also a key component of state and local economies and job creation efforts and is essential in order to maintain economic competitiveness.

Contact Us
The Planning Center of Expertise for Inland Navigation can be reached at (304) 399-5635.
Comments and requests for more information can be sent to

The state profiles provide an annual snapshot of waterborne commerce occurring in and around each state. These profiles provide an eye-opening view of how much cargo is transported on the inland waterway system and how each state plays an important role in the nation’s supply chain.

Navigation was the Corps of Engineers' earliest Civil Works mission, dating to Federal laws in 1824 authorizing and funding the Corps to improve safety on the Ohio and Mississippi Rivers and several ports. The Corps provides safe, reliable, efficient, and environmentally sustainable waterborne transportation systems (channels, harbors, and waterways) for movement of commerce, national security needs, and recreation.

What is a lock and dam system?

Major water transportation routes such as the Panama Canal and much of the navigable portion of the Mississippi River system are made possible by a series of locks and dams.

The dams form lakes, called navigation pools, behind them. Most pools in the United States are maintained at a constant minimum water depth of nine feet for safe navigation. Locks at each of the dams provide a passageway through the dam and more generally allow vessels to move through bodies of water that are at different water heights.

Why are lock and dams necessary for navigation?

Rivers often experience significant changes in water depth depending upon rainfall in their watersheds. Pools behind the dams provide reliable water depths for modern towboats pushing barges loaded with cargo.

Using locks and dams, massive ships can navigate through shallow or steep sections of river, traveling much further than natural terrain would allow.

Locks and dams can also be used to link waterways separated by natural divides. The Panama Canal is a good example. Vessels entering the Canal system at sea level on the Pacific side are stair-stepped through a series of locks to waterways at higher elevations, before being stepped through a series of locks back down to sea-level on the Atlantic side.

How does a lock work?

Boat locks work as a sort of "water elevator" to raise ships to higher or lower elevations. This is necessary to help big and heavy boats get through shallow or steep river areas.

A lock is a big chamber that sits in the water. It has rigid sidewalls and moveable gates at each end that can be opened to allow a vessel into the chamber and then closed once the vessel is on the chamber.

How does a lock work?
How does a lock work?
How does a lock work?
Photo By: USACE
VIRIN: 221230-A-A1409-018

For a ship going downstream, the lock is filled with water by opening the filling valve. Then the drain valve and upstream and downstream gates are closed so the chamber water level rises to the upstream level. Then the upstream gate opens and the boat moves in. To lower the boat, the gates are closed behind it, the filling valve is closed, and the drain valve is opened.

The higher water in the lock chamber drains to the downstream level in a few minutes. Then, the downstream gate is opened and the boat moves out on the lower water level. The process is reversed for a boat going upstream.