It may cost billions of dollars to keep Asian carp from invading the Great Lakes and ruining its fishing industry, the Army Corps of Engineers said in a new report.
In an extensive document, the corps detailed eight options for keeping the leaping giant—the fish, weighing up to 100 pounds, hurl themselves out of the water en masse when disturbed—from taking up residence in the largest surface freshwater system on Earth. The scenarios range from continuing the current practice of using electric barriers to keep the invasive species cordoned away from the lakes, to completely sealing off the Great Lakes watershed from the Mississippi River basin, which feeds into it.
The corps study focused on the Chicago Area Waterway System, which is where the two watersheds meet, and outlined “a wide spectrum of alternatives ranging from continuing current activities to complete separation of the watersheds,” the corps said.
“Potential aquatic pathways between the basins exist along the nearly 1,500-mile boundary of the two watersheds,” the corps said in its report. “This boundary is the primary focus.”
The invasive species, initially introduced to clean pond scum from catfish farms, has taken hold in most major waterways. The fish could threaten the Great Lakes $7 billion fishery industry.
To completely seal the boundary to carp would take an elaborate combination of screened gates, locks, electric and physical barriers; so-called nonstructural controls such as pesticides, education and physical removal of fish; buffer zones such as digging canals “to control up-and-downstream water flow,” and measures that would protect communities from flooding and drinking-water contamination, project manager Dave Wethington told the Associated Press.
The cost of the most extensive option could be as high as $18 billion and take 25 years, according to the report. The cheapest costs nothing, given that it involves keeping existing measures in place. The latter option consists of things like electrical barriers and chain-link fence across Eagle Marsh, which connects with a tributary to Lake Erie.
The Grand Traverse Band of Ottawa and Chippewa Indians sees the carp invasion as a sovereignty issue, given that the fish’s threat to other species puts their treaty rights in jeopardy. In 2010 the tribes joined the states of Wisconsin, Minnesota, Ohio and Pennsylvania in a lawsuit against the Army Corps of Engineers alleging that the agency wasn’t doing enough to guard the Great Lakes from this species. The issue is also part of the tribal council’s mission statement in the sovereignty section.
Starting January 9, the corps is holding public meetings throughout the Midwest through January 30, with some of them streamed online, the agency said in a media release. Public comment will also be accepted through the agency’s website through March 3.