Plans to block carp will re-reverse Chicago River
Andrew Stern - Reuters
This excerpt is from a Reuters article
Keeping the invasive Asian carp out of the Great Lakes will involve re-reversing the flow of the Chicago River -- an engineering marvel completed a century ago through a complex network of rivers, canals, and locks, a new study said on Tuesday.
The study proposed three options to separate the Great Lakes from the Mississippi River basin near Chicago and keep Asian carp and other invaders out but all three would require re-reversing the flow of Chicago river which now carries Chicago's treated waste water away from its Lake Michigan drinking water.
"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, sponsor of the study with several other interest groups.
The prolific Asian carp have populated the Mississippi River and many of its tributaries and now threaten the $7 billion fishery in the lakes, which contain one-fifth of the world's fresh surface water and supply 35 million people with drinking water.
The invasions by Silver and Bighead carp, first introduced to control algae in commercial fish ponds, have prompted promotional efforts to catch them as a source of cheap protein or for sport fishing, but their populations have exploded.
The U.S. Army Corps of Engineers, which is conducting its own long-term study on possible separation of the watersheds that is due to be completed in 2015, has erected electric underwater barriers at a canal bottleneck near Chicago to try to keep the carp at bay, but some marine experts fear the carp may have already bypassed the barriers.
Several states bordering the lakes have demanded stronger action and have filed a suit against the Army Corps calling for quick action to erect separation barriers and speed up its study.
Environmental groups backed the separation plans, with Marc Smith of the National Wildlife Federation saying the study "puts solutions on the table that are both feasible and affordable."