Lock Treatment System Needed to Stop Aquatic Invasive Species
We must stop the two-way movement of aquatic invasive species through the Chicago Area Waterways System.
Recently, the U.S. Army Corps of Engineers held a public meeting in Chicago on their proposed plan to stop aquatic invasive species (AIS) from passing through the Chicago Area Waterways System (CAWS). While we appreciate the Corps’ investment of time, consideration, and resources to develop these recommendations, we feel that they do not go far enough in protecting two of our country’s most valuable freshwater resources: the Great Lakes and the Mississippi River. Only one concept on the table has the potential to prevent the passage of AIS and maintain navigation: a Lock Treatment System.
There is no question that action must be taken to stop the two-way spread of aquatic invasive species (AIS) in the CAWS, a man-made connection between Lake Michigan and the Mississippi River. We also agree that per the Corps’ proposal, the Brandon Road Lock is the right place to start. Any potential invader that floats, swims, or is attached to shipping vessels must pass through this lock from the Mississippi River basin in order to enter the Great Lakes.
The Corp’s recently released study proposes a number of enhancements at the Brandon Road Lock: an engineered channel, an electric barrier, water jets, complex noise, and a flushing lock system. The total cost for their Tentatively Selected Plan is $275 million, of which $161 million is associated with the electric barrier.
We believe a more effective and less costly option is an AIS Lock Treatment System. With this solution, boats and barges would first pass through measures to deter fish, such as water jets and complex noise, as they move into an engineered channel with a treatment chamber. Once the chamber gates are closed, the held water is chemically treated to kill all organisms to prevent the passage of aquatic invasive species. After treatment, the chamber water is detoxified and the vessels released to the lock to complete their journey into the CAWS. The treatment system components and building are estimated to cost $43 million. The Corps’ engineered channel design can be modified to incorporate the treatment chamber, just leaving gates as the only other additional expense. This would cost significantly less than the electric barrier.
Two additional AIS Lock Treatment Systems will need to be located in CAWS to prevent AIS from Lake Michigan entering the Mississippi River basin.
It's no exaggeration to say that aquatic invasive species are one of the biggest threats to our native fish and wildlife, with significant economic impact in the Great Lakes. A 2012 report by Anderson Economic Group commissioned by The Nature Conservancy revealed that it costs hundreds of millions of dollars to control aquatic invasive species. Industries like sport and commercial fishing, water treatment, power generation, and tourism, as well as local residents who use the lakes for recreation, are all affected by this threat. With so much at stake, we urge the Army Corps of Engineers to seriously consider the lock treatment system option we’re proposing, so that these incredible freshwater resources are protected for people and for nature for generations to come.