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Enough is Enough: Plug the St. Lawrence Seaway

 Humankind has a rich history of conceiving environmental disasters. From profit hunting ignorance like the Exxon Valdez oil spill to honest mistakes like the “before 10am” wildfire suppression policy, we have committed atrocious crimes to our Earthly home, our living, and our nonliving neighbors. But few of these anthropocentric travesties have been as senseless and drawn out as the St. Lawrence canal.

The manmade trough connecting the Great Lakes to the Atlantic Ocean has been a highway for invasive species since its construction in 1959. Each decade brings a new hitchhiker from foreign waters, primed to decimate the ecosystems found in the largest freshwater source found anywhere on the planet’s surface. Now that environmental costs tower over the measly shipping profits derived from the seaway, we are out of excuses. Plug the St. Lawrence Seaway.

Prior to its construction, the five Great Lakes were isolated from the great oceans. No continuous route could be made between the freshwater oasis and the surrounding saltwater expanse. That ecological buffer was broken in 1965, when Queen Elizabeth proudly announced the engineering feat that was the Saint Lawrence Seaway. It’s hard to determine when exactly the Quagga and Zebra Muscles’ began their assault on the freshwater metropolis. The Eurasian species were both officially found in the 1980s. Since then they have become the dictators of all five lakes. NOAA Scientist Thomas Nalepa estimates that there are 437 trillion Quagga mussels in Lake Michigan alone, while Zebra mussels have been found in droves as strong as 700 thousand per square mile (p. 751, 2013). The mollusks’ dominance has brought  incredible strain to the lakes. Both species eat the microorganisms that serve as the foundation for all trophic levels in the lakes.

But the mussels are just two of the foreign species ravaging the lakes. Alewives, a small fish from the Atlantic Ocean, have pushed the delicate whitefish-walleye competitive balance to the brink. Sea Lampreys, another Atlantic invader, attach onto fish with razor-like teeth and quite literally sap the life out of their native host over two-to-four weeks. The Round Goby is a Caspian Sea native which feeds ferociously on the organic matter needed to support the bottom successional stage of life in the lakes (Eagan, pp. 22-35, 2017).

All of which have used the St. Lawrence Seaway to enter the Great Lakes.

The environmental crises felt within each drop of Great Lake water has taken financial, ecological, and intrinsic tolls wildly disproportionate to the gains made from the St. Lawrence Seaway. The U.S. Fish and Wildlife Service estimates that nonnative species cost the Great Lakes Region $200 million to control annually ( But those are only the costs incurred fighting these aquatic invaders. The commercial fishing, tourism, and sport fishing industries has been ravaged by these invasive species.

The Whitefish industry is valued at seven million dollars annually by the Michigan State Department of Natural Resources. Whitefish catches have been drastically declining and, in turn, the commercial fisherman in the great lakes region is a dying breed. Thousands of fishing businesses in the 1950s have shrunk to just 21 (Malewitz, 2019).

The economic losses from this ongoing ecological holocaust –both the quantifiable and the unquantifiable– cannot in anyway be justified by the St. Lawrence Seaway’s existence. University of Wisconsin urban planning researcher Harold Mayer explained the state of the Seaway’s usage,

“General cargo traffic between the Great Lakes and overseas has been declining rapidly since 1970, largely as the result of the rapid development of container ships, and the Interstate highway system, which increases the competitive advantages of salt-water ports. (p. 119, 1978).”

This trend has continued and, 42 years after Mayer’s findings, the Seaway accounts for just a sliver of the economic activity it was promised to produce. According to the U.S. Department of Transportation, the seaway accounted for $7.7 billion in cargo in 2018 ( Though billions annually seem sizable. The money made from these shipping ventures is largely diluted away from the Great Lake region. International corporations and foreign ships stock their hulls with cargo and fill their ballasts with noxious species, proceeding to drop off both in waters unimportant to them: the money largely leaves with each ship, but the environmental destruction remains.

The Great Lakes are dying. They are dying at the hand of a dying economic innovation: The Saint Lawrence Seaway. Its construction may have been an honest mistake. Its prolonged existence is a product of an inexcusable complacency by both the U.S. and Canadian Governments. Countless unspeakable ecological crimes have been committed by profiteers from half a world away, all the while our leaders have watched. For Decades. Enough is enough. Plug the St. Lawrence Seaway. Give the Lakes, its ecosystems, and its peoples the right to try and return to the delicate equilibrium that the five Great Lakes rely on.


  • NALEPA, T.F., J.S. Houghton, R. Paddock, and J. Janssen. Video Clip 3: Close-up view of inhalant siphons of quagga mussels (Dreissena rostriformis bugensis, deepwater morph) on the Midlake Reef Complex in Lake Michigan. In Quagga and Zebra Mussels: Biology, Impacts, and Control, Second Edition. T.F. Nalepa, and D.W. Schlosser (Eds.). CRC Press, Boca Raton, FL, 751 pp. (2013).
  • Mayer, H.M. Current trends in Great Lakes shipping. GeoJournal2, 117–122 (1978).
  • Egan, D. (2018). The death and life of the Great Lakes. New York: W.W. Norton & Company.