The Great Lakes Commission and the Great Lakes and St. Lawrence Cities Initiative released strategies at the end of January on how to prevent an Asian carp invasion of the Great Lakes by modernizing the Chicago Area Waterway System (CAWS).
“Physically separating the Great Lakes and Mississippi River watersheds is the best long-term solution for preventing the movement of Asian carp and other aquatic invasive species, and our report demonstrates that it can be done,” said Tim Eder, executive director of the Great Lakes Commission.
Concerns about Asian carp invading Lake Michigan grew in 2010 when the first live Asian carp, a Bighead carp, was caught beyond electric barriers in Lake Calumet, just six miles from Lake Michigan.
Asian carp, first imported to control algae in fish farms along the Mississippi River, escaped during a flood event in the 1990s. Since then, the carp have moved quickly up the Mississippi River and into the Illinois River, the Des Plaines River, the Chicago Sanitary and Ship Canal, and the Calumet-Sag Channel.
Asian carp can weigh up to 100 pounds, grow to a length of more than 4 feet, and, on average, eat up to 20 percent of their body weight in food each day. They are also extremely prolific. As such, Asian carp pose a major economic concern as they would outcompete other Great Lakes fish species.
Should the Asian carp get into the state’s inland lakes, especially in an area like Oakland County, their impact on the inland lakes’ ecosystems could be devastating, as well.
“When it comes to the spread of Asian carp, we are very concerned about inland waters. (Asian carp) can spread from the Great Lakes (into inland waters) just by moving naturally up the waterway. And we know that Asian carp do very well in small inland waters. While a spawning population may not be produced in such waters, if a number of them occupy the inland lake, it could disrupt that system’s food web,” said Tammy Newcomb, the Research Program Manager in the state Department of Natural Resources’ (DNR) Fisheries Division.
The recent report from the Great Lakes Commission, which is available at www.glc.org/caws, details three separation alternatives. They include a single down-river barrier between the confluence of the Chicago Sanitary and Ship Canal and the Cal-Sag Channel and the Lockport Lock; a mid-system alternative of four barriers on CAWS branches between Lockport and Lake Michigan; and a near-lake alternative of up to five barriers closest to the lakeshore.
All three of the measures include ways to improve the CAWS’ role in flood management, wastewater treatment, and maritime transportation, in addition to preventing the movement of aquatic invasive species.
According to the report, the total cost of one of these projects varies between $3.2 billion and $9.5 billion, depending on the improvements needed to address water quality, flood prevention, and transportation. The construction of the barriers themselves could cost as low as $109 million.
Michigan Attorney General Bill Schuette, who by statute serves on the Great Lakes Commission, praised the speed with which the study was conducted.
“Asian carp are knocking at the front door of the Great Lakes, so we simply do not have until 2015 to complete a study. We need to get started separating these two bodies of water as soon as possible,” Schuette stated in a press release. “The Great Lakes Commission accomplished in months what the Army Corps (of Engineers) hasn’t been able to do in years. With thousands of jobs and a spectacular ecological resource at stake, we can no longer afford to wait for the federal government.”