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Great Lakes Ports & Shipping

4 | Travel between ports

Click for more port information. Ships typically travel in upbound or downbound shipping lanes between ports on the lakes to avoid collisions. If a vessel is downbound, it means that it's headed out of the Great Lakes toward the Atlantic Ocean. Likewise, if a vessel is upbound, it is headed west from the Atlantic Ocean to the Great Lakes.

There are 15 major international ports and some 50 smaller, regional ports on the Great Lakes-St. Lawrence Seaway system. Some of the larger ports include the following:

Click to see larger image.On the Great Lakes (and all U.S. waterways), cargo moving between ports is governed by the Jones Act. The Jones Act is one of several U.S. cabotage laws, which reserve all forms of transportation to American companies employing American workers. The rules of the Jones Act also ensure that shipping on U.S. waters is governed by the world's highest safety and operational standards. The U.S. Coast Guard oversees every aspect of U.S.-Flag shipping on self-propelled vessels, including construction and ship maintenance, and qualifications of the crew.

Issues facing the shipping community
Navigation maintenance dredging: Dredging involves the periodic removal of accumulated sediments on the bottom of waterways, harbors and shipping channels. Commercial navigation could not successfully continue on the Great Lakes without dredging. A ship's draft is the depth of water needed to float a ship. A slight decrease in the depth of a waterway means that a vessel must decrease its draft (i.e., reduce the amount of cargo that its carrying). For example, a 1,000-foot vessel will lose 270 tons of cargo for each inch reduction in its draft!

What to do with dredged material is also a growing issue in the Great Lakes region. In-water disposal was common in the late 1960s but after a century of industrial activity and related pollution around port cities, some of the dredged material now contains highly contaminated sediments. Since dredgers don't want to return these polluted substances back to the lakes, confined disposal facilities (or CDFs) have been built. Also beneficial uses, such as beach nourishment, landscaping and road construction fill, are being explored for the non-polluted dredged material.

More about dredging and contaminated sediments

Ballast water management to prevent the spread of invasive species: Ballast is a heavy substance (in most cases water) used to improve the stability and control the draft of a ship. Research has shown that many of the non-native invasive species, like zebra mussels, that have invaded the Great Lakes have traveled in the ballast water tanks of ships. Since prevention is the key to blocking future introductions, ballast water management is now a priority of the shipping community. U.S. law and Canadian policy now requires an exchange of ballast water in the ocean before a vessel can enter the freshwater system. Other experimental techniques involve filtering, heating or chemically treating the ballast water to kill any unwanted critters that are looking to find a new home in the Great Lakes.

More about ballast water treatment

Graphics: Port of Thunder Bay, Ontario, on Lake Superior; Indiana's International Port at Burns Harbor on Lake Michigan

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