Invasive Asian Carp Pose Threat to Great Lakes Ecosystem

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The invasive Asian carp, weighing up to 100 pounds and eating 10% of their weight in algae daily, are marching toward the Great Lakes and could pose an existential threat to the region's ecosystems and fishing industries. While a multi-state coalition has been working on a project to build an elaborate system of deterrents at the Brandon Road Lock and Dam to keep the carp out, delays in federal funding have stalled progress, raising concerns about the potential catastrophic impact if the fish reach the Great Lakes.

Why it matters

The Asian carp are an invasive species that could devastate the Great Lakes' delicate ecosystems and disrupt the region's vital commercial and recreational fishing industries if they gain a foothold. Preventing their spread is critical to protecting the ecological and economic health of the Great Lakes.

The details

The four species of Asian carp - bighead, silver, black and grass - were introduced to the U.S. in the 1960s and 1970s and have since spread through Midwest waterways, with their populations booming. The fish pose concerns not only for disrupting food chains and competing with native species, but also for navigation and boater safety, as the startled silver carp can leap several feet out of the water and injure people. To keep the carp out of the Great Lakes, the Army Corps of Engineers developed the Brandon Road Interbasin project, a multi-layered system of deterrents including acoustic and electric barriers, an air bubble curtain, and a redesigned lock and channel. However, the project has been delayed due to a pause in federal funding shortly after President Trump's second inauguration.

• The Asian carp were introduced to the U.S. in the 1960s and 1970s.
• The Army Corps of Engineers began operating an electric dispersal barrier in the Chicago Sanitary and Ship Canal in 2002 to prevent the carp from spreading into the Great Lakes.
• Two additional barriers became operational in 2009 and 2012.
• The Brandon Road Interbasin project was authorized in the Water Resources Development Act of 2020 and supported by the Bipartisan Infrastructure Law with $272 million in funding over two years.
• In May 2025, President Trump directed his administration to implement barriers/measures to keep invasive carp out of the Great Lakes, but singled out Illinois for delaying the project.

What they’re saying

What’s next

The federal government is reviewing the Brandon Road project and has not yet released the critical funds needed to move the project forward. Governors Whitmer and Pritzker, along with Sen. Durbin, have called for the funding to be released so construction can begin as soon as possible to prevent the Asian carp from reaching the Great Lakes.