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A Huge Underwater Electric Fence Is the Great Lakes’ Big Hope Against a Carp Invasion
If they make it past the Chicago River, the results could be catastrophic
The barrier facility looks just like every other stretch of the industrial riverfront several dozen miles outside of Chicago. Coal, gas, and concrete operations joust for space along the shoreline. Stacks send plumes of smoke and flame into the sky. But on this expanse of the Chicago Sanitary and Ship Canal, an alchemy takes place underwater: electrically charged water creates a “fence” intended to stop fish from passing through to the Great Lakes.
This unusually extreme method of aquatic control is run by the U.S. Army Corps of Engineers near Romeoville, Illinois. The facility requires round-the-clock maintenance to keep two electric barriers sending pulses of direct current across a canal that’s nearly 30 feet deep and 160 feet across. The elaborate setup is an attempt to keep out one of the most relentless invasive species in the United States: Asian carp. If these fish ever reach the Great Lakes, the consequences could be catastrophic.
The name Asian carp actually applies to four species of fish: bighead carp, silver carp, grass carp, and black carp. In the 1960s, all four were introduced into commercial fish ponds in the…
