The silver carp is large and clumsy, and Joe Grindyk has to measure it with both hands before tossing the fish overboard into the Illinois River. The nearly 2-foot-long invasive fish now inundating the river has become the centerpiece of a government monitoring program aimed at curbing its rapidly growing numbers.
“They're pretty slimy and pretty strong,” said Grindyk, a seasonal angler at the Illinois Institute of Natural History (INHS), his hands coated in fish slime. “So if you don't grab them correctly, they can be quite difficult to control.”
For decades, local, state and federal officials have worried that the voracious filter feeder, which can eat and outgrow native fish, could bypass Chicago and enter the Great Lakes. There are fears that the carp, which are leaping out of the water and spooking boaters, could reduce populations of native species that locals love to fish for and wreak havoc on the world's largest freshwater ecosystem and the multibillion-dollar tourism, boating and fishing industries that depend on it.
But the battle to keep the carp under control and out of the Great Lakes may now be getting easier. Last week, the state of Illinois announced it had acquired the land needed to build the Brandon Road Interbasin Project, a $1.15 billion barricade designed to keep water threats out of the canal connecting the Mississippi River basin to the Great Lakes.
The Brandon Road Interbasin Project, or BRIP, is an underwater protection system that has long been considered a solution to the carp problem. The project, developed by the U.S. Army Corps of Engineers, is planned to be built on the Des Plaines River, which connects the Illinois River to the Chicago Ship Canal, near the suburb of Joliet. Upgrades to the lock and dam will include a bubble wall, acoustic blasts, an electrical barrier and a flushing mechanism to prevent carp from passing through.
Ashley Rezin/Chicago Sun-Times
The infrastructure project stalled earlier this year due to disagreements between President Trump and Illinois Gov. J.B. Pritzker over federal funding and immigration enforcement. Trump has frozen more than $100 million in federal funds promised to Illinois. In response, Pritzker delayed the initial land transfer of a 50-acre riverbed site from Midwest Generation, the former operator of a coal-fired power plant near the site of the proposed project, to the state. Without this, the Army Corps would not have been able to begin site preparation for the project.
But by spring, the Army Corps told Illinois officials it had received funds to begin clearing the riverbed, and Pritzker and the White House renewed efforts to move forward with the project. Allen Marshall, a spokesman for the Army Corps' Rock Island District, confirmed that the project phase was completed in July.
Tensions rose again in late summer with Trump's threats to send the National Guard to Chicago to fight crime and tighten immigration enforcement. In late August, Trump told reporters in the Oval Office that Pritzker was not cooperating in efforts to get rid of the carp. “The governor of Illinois has suffered perhaps more than anyone else,” Trump said. “I guess until I get that request from this guy, I won’t do anything about it.”
Nevertheless, the megaproject is being implemented. Illinois officials announced last week that they had reached an agreement on Sept. 30 for two small mountain sites totaling 2.75 acres needed for the project. However, this donation could come at a cost to Illinois taxpayers.
Previous report from VBEZ And Fall asleep revealed long-standing concerns among government officials about the site's contamination from coal ash, a toxic byproduct of burning coal. Pritzker has raised concerns about the cost of cleaning up the toxic mess in 2024. letter to the Corps.
“It would be irresponsible to write a blank check to the Corps of Engineers or any other project manager without a better understanding of what we are agreeing to in the long term,” a Pritzker spokesman said in a statement at the time.
The Illinois Department of Natural Resources confirmed that state officials are currently developing a plan to investigate the site and are considering whether any additional land is needed.
But despite these concerns, regional leaders are pushing ahead with funding for the project. Earlier this month, Pritzker joined six other Great Lakes state governors in introducing letter Congress, calling BRIP a “national priority” and calling on lawmakers to provide full federal funding for the project.
The invasive carp – a family of fish that also includes silver carp, black carp and grass carp – first appeared in the Mississippi River about 50 years ago. Experts say the fish began crowding the waterway after leaving Arkansas fish farms where they were imported to limit the growth of algae and weeds. Over the years, the fish expanded its range throughout the river and its tributaries and began to dominate the Illinois River in the 1990s.
Ashley Rezin/Chicago Sun-Times
In 2019, INHS partnered with the Illinois Department of Natural Resources to create an interagency program to monitor the relative abundance of carp up and down the Illinois River. As part of the program, environmental teams catch and monitor the health of carp and native fish between June and October each year.
This data helps the state stay ahead of the carp. If carp populations in one stretch of river increase dramatically, Illinois officials can tailor harvest incentives, the state's primary form of carp control. The program involves contracting with commercial fishermen for a target catch and paying an additional 10 cents per pound of carp. The attempt seems to be working.
“According to this data, we are causing increasing harm to the population,” said Michael Speer, a quantitative ecologist at INHS. “This incentive appears to be paying off.” He pointed to an area near Starved Rock State, one of the northernmost stretches of the more than 270-mile river, where he noted a sharp decline in the carp population over the past five years. The state Department of Natural Resources had not provided a detailed estimate of carp declines at the time of publication.
Spear watched from the stern of the sampling boat as Grindyk and the rest of the crew completed the day's work. While the data is encouraging, he said no one wants to find out what happens if the carp make it upstream from Chicago.
“Carp may be absent from some other Great Lakes states,” Speer said. “But these states are paying a lot of attention because if they get into the Great Lakes, it becomes a much more regional problem.”
