In a long-awaited report, the U.S. Army Corps of Engineers says new measures are needed to prevent Asian carp from getting into the Great Lakes.
The report says the current defense at the Brandon Road lock in Illinois – an underwater electric barrier – should be beefed up. The Army Corps' recommended plan would add water jets and complex noises – like the underwater recordings of a boat motor.
The total cost of implementing the Army Corps’ “Tentatively Selected Plan” is estimated at $275 million, with 65 percent coming from the Army Corps and the rest from non-federal contributors.
The report analyzes three ways that invasive species like Asian carp enter the Great Lakes: swimming, floating, or hitchhiking. The recommended plan -- which does not include the closure of the Brandon Road lock -- includes several measures that the Army Corps says will help restrict Asian carp:
- Nonstructural methods (which includes educating the public, further research on effectiveness of tools, and manually removing invasive fish)
- Complex noise -- an underwater sound
- Water jets – designed to remove small fish
- Engineered channel – a structure installed downstream of the Brandon Road lock
- Electric barrier – electric shock that stuns fish, placed downstream of engineered channel
- Flushing lock – exchanges water from upstream prior to lock closing – removes floating invasive fish from the lock
- Boat launches – upstream and downstream of Brandon Road Lock and Dam
- Mooring area – located two miles downstream of Brandon Road Lock and Dam
The Alliance for the Great Lakes and other environmental groups said in a joint statement Monday:
"We look forward to reviewing the findings in detail and to continuing the conversation on this critical issue with elected officials and concerned citizens during the public comment period. The U.S. Army Corps of Engineers must listen carefully to public input on the study and then move quickly from study to implementation ... "
Millions of dollars have been spent to keep the invasive species out of the lakes, and defenses are concentrated near the southern tip of Lake Michigan.
Two varieties -- the Silver and Bighead -- pose the biggest threat because of their voracious feeding habits. They consume lots of zooplankton, the microscopic animals that other fish feed on.
In June, a live Asian carp was discovered nine miles from Lake Michigan – beyond the electric barrier.
Politicians have raised concerns too, including Illinois Lt Gov. Evelyn Sanguinetti. Earlier this year, Sanguinetti called the Brandon Road plan an “unnecessary experiment.” In a statement Monday, Sanguinetti says the Army Corps’ recommended plan is “neither cost effective nor environmentally sound.” She says the $275 million project will hurt her state’s economy.
A bipartisan group of Congressmen and Senators recently introduced the Stop Asian Carp Now Act in Congress.
The Army Corps will accept public comment on the study until Sept. 21, and will hold two public meetings.