It was just last week this column reported officials plan to poison a 5.5-mile portion of the Chicago Sanitary and Ship Canal as a temporary measure to keep destructive Asian carp from reaching the Great Lakes while engineers work on one of two electric fish barriers near Romeoville.

Since then, they say tests have revealed the measure may already be too late.  The University of Notre Dame notified the U.S. Army Corps of Engineers water samples taken from the area between the barriers and Lake Michigan tested positive for DNA from Asian carp. 

Three species of fish, the bighead, silver and black carp, are collectively known as Asian carp. They were released into the Mississippi River when stocked ponds were flooded several years ago. Silver and bighead carp are filter-feeding fish that grow huge eating vast amounts of plant and animal plankton, which all fish eat when they’re small. Biologists fear competition could hurt multibillion dollar sport fisheries throughout the Great Lakes.

The IDNR and Army Corps will still go ahead and use the poison in the first week of December while the corps tinkers with the newer permanent electric barrier, officials said.  A temporary barrier in place there for several years apparently isn’t enough to guarantee more potentially destructive fish won’t move closer to Lake Michigan while the new barrier is offline for maintenance. 

The poisoning process, which might have to be repeated in six months, will cost $1 million to $2 million.

The recent tests, which detect trace amounts of DNA, were conducted on water samples taken Sept. 23 and Oct. 1 about eight miles from Lake Michigan, officials said.  It’s the first time any sign of the carp has been reported beyond the barriers.  The main advance of Bighead and silver carp remains in the Illinois River near Starved Rock State Park at Utica.

 “We will continue to work with the group and our partners on how best to address this new issue and move forward with achieving our overall goal,” said IDNR Assistant Director John Rogner.

In response to the recent development, the Natural Resources Defense Fund repeated its belief Lake Michigan can only be protected by closing the manmade century-old connection between the lake and the Illinois River/Mississippi River waterway, which is referred to as the Chicago Diversion.

  “The Army Corps of Engineers needs to stop reacting to events, and get ahead of this problem with real solutions,” said Henry Henderson, director of the Natural Resources Defense Council’s Midwest Program.

“Physical barriers in the waterways need to be put in place quickly, along with a clear plan to move aggressively toward closing off the Chicago Diversion and returning the ecological barriers that used to protect the Great Lakes from these threats. The only thing aggressive about the virtual fish fence has been its multi-million dollar price tag.”

Scott Richardson is Pantagraph outdoor editor.  Contact him at (309) 820-3227 or e-mail srichardson@pantagraph.com.  Share stories and read past outdoor and fishing columns at

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