The U.S. Army Corps of Engineers has proposed spending $275 million to upgrade defenses against an invading force. The enemy? A fish. Specifically, Asian carp that are threatening to break through to the Great Lakes.
In June, a live Asian silver carp was caught in the Illinois Waterway just 9 miles from Lake Michigan. Scientists fear that if the voracious carp establish themselves in the Great Lakes, they could devastate the region's $7 billion fishing industry.
The Corps of Engineers wants to upgrade the Brandon Road Lock and Dam near Joliet, Ill., on the Des Plaines River. The waterway is a link between Lake Michigan and the Mississippi River, where Asian carp are already a big problem. The Associated Press writes, "The Brandon Road complex is considered a bottleneck where defenses could be strengthened against fish swimming upstream toward openings to the lake at Chicago."
The 488-page report also details plans to block the path of the fish "while minimizing impacts to waterway uses and users." The report also looks to using underwater sound systems to deter the fish, building a new approach channel in the Brandon Road area and placing using an electrical barrier to stun fish at the downstream end of the waterway.
The draft report had originally been expected in late February, but its release was blocked by the White House, which wanted to conduct a review.
According to Scientific American:
"Seven species of carp native to Asia have been introduced into United States waters in recent decades, but it's four in particular—bighead, black, grass and silver—that worry ecologists, biologists, fishers and policymakers alike. Introduced in the southeast to help control weeds and parasites in aquaculture operations, these fish soon spread up the Mississippi River system where they have been crowding out native fish populations not used to competing with such aggressive invaders. The carps' presence in such numbers is also compromising water quality and killing off sensitive species such as freshwater mussels."