A century ago, engineers cut the Chicago Sanitary and Ship Canal, connecting the Great Lakes with the Mississippi Basin. It might be time to close the canal:
Over the last decade or so, a huge range of interests — from environmental groups to fishermen to shipping experts to politicians — have raised the alarm over just how much this artificial connection has created an opening for invasive species such as the Asian carp to make their way through North America’s waterways. And the costs associated with the damage caused by these species have been high enough to prompt serious consideration of closing off the link between the Mississippi and the Great Lakes.
How high? First, consider the figure $18 billion. That’s the estimate the U.S. Army Corps of Engineers released last week to re-insert a physical separation between the Great Lakes and the Mississippi system.
The proposal would dam the Chicago and Calumet Rivers' connections to the Canal, requiring changes to the Deep Tunnel reservoir system and the flood-control systems in the Western suburbs. Meanwhile, Asian carp have gotten within a few kilometers of Lake Michigan. Twenty of those fish in the lake is all it would take to create a permanent population all the way to the Gulf of St. Lawrence.
Reversing the Chicago River made a lot of sense in 1900, and probably saved thousands of lives from cholera and other diseases. Times change, though. We have new threats today.