Long-delayed Army Corps report outlines plan to stop Asian carp from infesting Great Lakes

Asian carp (Wisconsin Department
of Natural Resources photo)

The U.S. Army Corps of Engineers released a draft report Aug. 7 detailing a $275 million plan to keep invasive Asian carp from entering the Great Lakes via Chicago-area canals that lead to Lake Michigan. "The best way to keep invasive Asian carp from entering and wreaking havoc on the Great Lakes would involve a series of water jets, flushing locks and electrical barriers on the Illinois River," Cecelia Smith-Schoenwalder reports for Environment & Energy News.

The 488-page study focuses on the Brandon Road Lock and Dam in Joliet, Ill., which occupies a critical strategic point in the Illinois River system. The plan entails a series of physical and nonphysical barriers, some using experimental technology, to keep the fish from passing through. Proposed barriers include water cannons, noise obstacles, electrical barriers, boat launches, and more. Marc Smith, the conservation director for the National Wildlife Federation, says the NWF likes the concepts, but "we also know that this is not enough." Some barriers are not completely effective on their own, but the effects of so many working in tandem have not been studied. Would the combination of barriers increase effectiveness or could they cancel each other out sometimes and let a few fish through?

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The complexity of all these factors together is one reason the Corps says the report, which was due in February, was delayed so long. Lawmakers and environmental groups complained that the delay wasted time and put the Great Lakes in danger, and introduced several bills to demand that the report be released. A dozen Democratic senators from eight Great Lakes states sent a letter to the Trump administration on April 10 requesting the release of the plan. The request took on added urgency after a live carp was discovered just nine miles from Lake Michigan, 34 miles closer to the Great Lakes than ever before, and far past an electric barrier designed to keep them out.

Now the Army's old slogan "hurry up and wait" comes into play. The Corps will accept comments from the public about the plan until Sept. 21, and will schedule several public meetings to discuss the report. "After a feasibility study and series of federal and state reviews, a final report is scheduled for release in August 2019, John Flesher of The Associated Press reports. 'Congressional approval and funding would be required to get construction underway."

The major players all know that every carp that makes it into a Great Lake is a problem. Marc Gaden of the Great Lakes Fishery Commission said as few as 10 males and 10 females could establish an Asian carp population in the Great Lakes. They would directly compete with bass and walleye for habitat, and would "completely disrupt the food chain. Asian carp would dine on the plankton and small plant materials at the bottom of the food chain, causing population declines in forage fish," Smith-Schoenwalder reports.