The Great Lakes serve as the nation's fourth sea coast by transporting vital commodities to and from the nation's heartland. The communities around the Great Lakes and its tributaries have strong historical ties to waterborne transportation, and total annual commerce averages 175 million tons. 

The Great Lakes navigation system is a continuous 27-foot deep draft waterway that extends from the western end of Lake Superior at Duluth, Minn., to the Gulf of St. Lawrence on the Atlantic Ocean, a distance of over 2,400 miles. This bi-national resource--between Canada and the United States--is composed of the five Great Lakes, the connecting channels of the Great Lakes, the St. Lawrence River and the Gulf of St. Lawrence.

The US Army Corps of Engineers helps to maintain Great Lakes navigation through dredging of channels and harbors, and construction and maintenance of coastal infrastructure.

The communities around the Great Lakes and its tributaries have strong historical ties to waterborne transportation. Commercial and industrial development was concentrated along waterfronts because of the navigation access. Harbors became the focal point of many Great Lakes cities.

The Great Lakes serve as the nation's fourth sea coast by transporting vital commodities to and from the nation's heartland. Waterborne commerce is critical to the regional and national economy. Commercial navigation on the Great Lakes is dominated by the transport of raw materials for steel making, coal-fired power production and construction materials such as limestone, cement, stone gravel. Total annual commerce on the Great Lakes averages over 175 million tons

The St. Lawrence Seaway is a dynamic, international waterway stretching over 2,000 miles from the Gulf of the St., Lawrence Seaway on the Atlantic coast to the tip of Lake Superior at Duluth, Minnesota. The Great Lakes St. Lawrence Seaway generates $5 billion annually in income and directly supports 67,000 jobs. In addition, recreational boating contributes approximately $9 billion annually to the regional economy.

The U.S. portion of the system includes 140 harbors (60 commercial, 80 recreational), two operational locks, 104 miles of breakwaters and jetties, and over 600 miles of maintained navigation channels. In addition, the GLNS is connected to several other shallow draft waterways (Illinois Waterway, New York State Barge Canal, etc.) to form an important waterborne transportation network, reaching deep into the North American continent.

The Great Lakes system includes 47 deep draft ports and 55 shallow draft harbors. Waterborne commerce is more economical and environmentally sound form of transportation and is made possible by partnerships with government agencies and industry in both the United States and Canada.

• The Corps of Engineers has proposed a new lock at Sault Ste Marie, Michigan to keep pace with the demands of the commodities being shipping from Lake Superior to the rest of the Great Lakes system.
• Currently 86 million tons pass through these locks. Over 75 percent of the iron ore produced in the United States transits through the Soo locks and many large vessels are limited by the size of the locks.

Currently the Corps of Engineers is involved in a unique binational study to determine current baseline information for environment and engineering features and economic conditions of the Great Lakes St. Lawrence Seaway System.  The study will evaluate the social, environmental and economic impacts of future investments to operate and maintain the existing navigation system.

Great Lakes navigation requires maintenance by dredging channels and harbors. Approximately 25 activities a year remove 2-4 million cubic yards of lake bottom material. In addition to maintaining the channels for navigation, the Corps of Engineer’s dredging program benefits environmental restoration of the Great Lakes. Over 90 million cubic yards of contaminated sediments, which threaten the health of the surrounding 8 states, municipalities and the fisheries, have been removed and safely confined.

In addition to dredging operations, safe operation and maintenance of the 734 miles of Great Lakes navigation channel is possible by the Corps of Engineers ongoing activities to map and survey the lakes, build and maintain 150 miles of breakwater, operate and maintain 25 lock chambers and 44 confined disposal facilities for dredge materials.