Electric Barrier to Stop Asian Carp Approaching Great Lakes

An electric barrier on the Chicago Ship and Sanitary Canal in Romeoville designed to contain the nonnative, invasive round goby within the Great Lakes and out of the Mississippi River (CW, Summer 1999) has a new charge — to keep Asian carp from swimming the other way.

Two species of Asian carp — bighead and silver — were introduced into the southern United States from eastern Asia for use in aquaculture. They escaped from fish ponds into the Mississippi River and are now in the Illinois River within 30 miles of the electric barrier. These exotic carp can grow to 100 pounds and four feet, are prolific reproducers, and compete with native fish for food. They are currently found only on the Mississippi side of the barrier. "Predicting the Asian carp's impact is to some extent an educated guess, but the risk is great," states John Rogner, field supervisor with the U.S. Fish & Wildlife Service. "We don't want to introduce this species to the Great Lakes system."

Asian carp are filter feeders — they swim with their mouths open, filtering plankton out of the water. The native fish of this region also need plankton to feed and grow. "A second barrier is essential," asserts Gene Fleming, U.S. Army Corps of Engineers (USACE) chief of the Environmental Formulation and Analysis Branch. "Fish wait at the barrier. If we shut one down to do routine maintenance, the fish will get in." The Sanitary Canal is the only aquatic link between the Mississippi River and the Great Lakes.

The USACE has accelerated work on the project and approval is expected before spring. "Hopefully work will begin on the second barrier in August and we'll finish it in a year," stated Fleming. The new barrier will be constructed within 4,000 feet of the first one.

The Corps' project has received important support from Representative Judy Biggert (R-IL). Biggert co-sponsored legislation clearing the way for construction of a second electric barrier. She also co-sponsored the Aquatic Research Species Act, which provides funding to help scientists better prevent invasive species from inflicting damage on the environment and the economy. "We must pass these bills and we must do it fast," said Biggert. "Make no mistake: the Asian carp waits for no one — not even Congress."

— Alison Carney Brown