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Scott Whitney of the Army Corps of Engineers stands on a Des Plaines River peninsula carved nearly a century ago to make way for the Brandon Road Lock and Dam in Joliet.
As the Army Corps’ chief of project management, Whitney helps ensure that the invasive carp that took over parts of the Illinois River in the 1990s don’t make it to the other side. Soon, the Army Corps could put into motion its nearly decade-long plan for this site and create a barrier to those pesky fish.
To prevent these prolific fish from leaving Illinois waterways and reaching Lake Michigan and beyond, the Army Corps plans to build a $1.416 million set of high-tech barricades to deter the fish from moving upstream. . The Brandon Road Interbasin Project It could take at least six to eight years to complete once it is built. The Army Corps and the state department of natural resources are still working to finalize a partnership agreement.
“One technology alone is no good, but four or five technologies together will give us what we need,” Whitney said of the megaproject that will include an electric barrier, a bubble wall, sound blasts and a discharge lock.
Invasive carp is short for a family of giant fish that can eat, grow, and reproduce more than native fish. In parts of the Illinois River, researchers say there are more carp than anywhere else on the planet. The carp populations further upstream are found approximately 14 miles downstream. But Whitney and other scientists worry that there are increasing opportunities for carp to survive and disrupt the food web within the Great Lakes. Carp could decimate the entire recreational and commercial fishing industry that has sprung up around the lakes and is valued at $7 billion a year.
“The fisheries resources of the Great Lakes are a phenomenally rich resource that represents billions of dollars a year,” Whitney said. “Fish that come and feed at the bottom of the food chain affects the entire ecosystem.”
Whitney said on any given day about 15 barges carrying petroleum products pass through here. The river has been an important economic thoroughfare since Illinois decided to open the Great Lakes to the Mississippi River starting in the 19th century with a system of canals.
The union of the two basins made Illinois an important connector for a trade route from the Gulf of Mexico to beyond Canada. Each year, hundreds of tons of goods and commodities worth billions of dollars flow through the Chicago Sanitary and Ship Canal.
There is a place near the confluence of the Illinois and Des Plaines rivers that the fish simply won’t cross. Scientists have theorized that pollution in Chicago’s waterways has kept carp in check for years.
“If you sample fish from that leading edge and compare them to those from the downstream edge, we see higher rates of stress in animals that live on the upstream edge,” said Cory Suski, professor of aquatic resources at the University of Illinois. Urbana-Champaign.
Suski found that fish closest to Chicago showed signs of greater exposure to pollutants than their downstream counterparts. More recently, Suski and his collaborators tested how young silver carp behaved in river water. Chicago Area Waterways System (CAWS). They discovered that the carp’s behavior was incorrect and that simply inhabiting the water upstream required more energy than usual.
But the water quality at CAWS is better than ever. Although 70% of the water in the CAWS comes from wastewater treatment facilities, fish species are beginning to thrive there. And that is a concern.
“There is a lot of work being done to improve water quality.” Suski said. “And if something changes, maybe we could start to see a change in carp movement.”
According to Molly Flanagan, there are already more than 180 invasive species in the Great Lakes. she is with him Great Lakes Alliancean advocacy organization working to protect the interconnected freshwater ecosystem.
Flanagan says carp could turn Lake Michigan into a propagation pathway.
“The concern is that invasive carp will reach the lakes through the Chicago Canal,” Flanagan said. “And then they move into rivers and streams in the Great Lakes region.”
Whitney, of the Army Corps, said that is why construction of the megaproject is necessary.
“We rarely have opportunities like this, to really stop something in its tracks, because usually, once they’re here, they’re here to stay,” Whitney said.
This story was originally published on January 24, 2024. It is republished with permission.
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