The Asian carp "fish barrier" that is supposed to stop this invasive species from entering Lake Michigan and devastating the Great Lakes, as the fish has done in parts of the Mississippi River system, is remarkably nondescript. Experts agree that the barrier is not enough to stop the Asian carp invasion, so what measures are needed? And what does the future hold for the Great Lakes and the Mississippi River?
When you scope out the scenery from the middle of the 135th Street Bridge in Romeoville, Illinois—the bridge that spans the DesPlaines River and, just to the east, two canals that follow the river’s course—you can’t help but be awed by one of America’s epic industrial landscapes.
To the north, a Citgo refinery sprawls for a mile and a half through the flat river plain, a masterful and bewildering array of tanks and pipes and spindly fraction towers that rise like minarets of the industrial age. From a fat smokestack on this calm March morning, an exclamation point of steam, thick, monolithic and white as snow, gleams radiantly against the blue sky. To the south of the bridge another plant, this fronted by a tremendous pile of coal, pitch black, waiting to feed the power plant that squats here beside the waterways.
Then there are railroads—trains with a hundred cars and more come speeding by. One heads north, air horn blasting, metal wheels rumbling, and soon another heads south, tracing the canal’s edge to who knows where. The jewel of the neighborhood is just up around the bend toward Chicago, the Argonne National Laboratory, where America first learned to make electricity from radioactive elements.
Indeed, the river plain has evolved into a dramatic technological stage where modern and ancient converge, and as such is curiously fitting for another facility recently added here, one that you barely notice perched down on the cutstone bank of a century-old canal. This facility presents as just a gray metal pole building about the size of a doublewide, but like its neighbors it is also involved in an epic drama involving man and nature and, also like its neighbors, is in part a shrine to the principle of unintended consequences—in this case fish that escaped captivity and threaten to take over America’s two vast freshwater realms—the Great Lakes and the Mississippi River system.
Called the Chicago Sanitary and Ship Canal Aquatic Nuisance Species Dispersal Barriers, or “the fish barrier” for short, the little pole building and the electric current it shoots into the water here about 30 miles southwest of Chicago’s waterfront is all that prevents invasive varieties of Asian carp from swimming north to Lake Michigan. If the carp barrier fails and fish thrive in the Great Lakes, some people fear the carp could consume a huge percentage of the plankton that makes up the base of the food web, possibly dramatically reducing populations of small forage fish and ultimately reducing numbers of game fish like lake trout, salmon and smallmouth bass that Midwesterners have come to cherish. The impacts would not be limited to underwater, either. One variety of Asian carp, the silver carp, leaps from the water when disturbed by boat motors and has caused concussions, broken people’s jaws and in at least one case, knocked a jet skier unconscious.