Army Corps considers new front in Asian carp war

TRAVERSE CITY, Mich. - A new line of defense against invasive Asian carp may be opened on a river near Chicago in hopes of providing further short-term protection for the Great Lakes while a permanent solution is debated, officials said Tuesday.

The U.S. Army Corps of Engineers announced plans to consider measures that could be used to block the path of bighead and silver carp at Brandon Road Lock and Dam on the Des Plaines River near Joliet.

The site is about 5 miles downstream from electric barriers on which the Army Corps now depends to prevent the aggressive carp from reaching Lake Michigan, where scientists say they could starve out native fish and eventually spread to the other Great Lakes. The barriers are in the Chicago Sanitary and Ship Canal, about 37 miles by water from the lake.

If effective obstacles can be mounted at Brandon Road, the site could stop Asian carp and other exotic fish species from using the Des Plaines River to reach the sanitary and ship canal and other area waterways that lead to the lake.

Brandon Road's potential as a choke point "makes it an ideal location to evaluate potential control technologies," project manager Dave Wethington said.

Aside from creating additional electric fields in the water, the Corps might use air cannons or special gates with flushing chambers to stop invasive species from being pulled between water bodies in currents created by boat traffic, he said.

A Brandon Road barrier wouldn't be a final solution, in part because it wouldn't be a two-way obstacle that would stop invaders native to the Great Lakes from reaching the Mississippi River system. But it would be far less expensive than the complete physical separation demanded by environmentalists and some Great Lakes states, which could cost up to $18 billion and take 25 years to complete, Wethington said.

And it would buy time as the search for a final answer continues.

"We've heard from stakeholders that they're looking for something to be done more rapidly than not," he said.

A public comment period will run through Jan. 17, 2015. Public meetings are scheduled for Dec. 6 near Joliet and Dec. 9 in Chicago.