Aquatic Nuisance Species Dispersal Barrier

Limiting Invasive Species on the Chicago Sanitary and Ship Canal

Apr 9, 2009

Natural resource agencies are cooperating to prevent passage of invasive non-indigenous fish species with an electric barrier while protecting the safety of boaters.

Boaters operating in Illinois on the Chicago Sanitary and Ship Canal (CSSC) will encounter something new in the water because of efforts being made to prevent the migration of aquatic invasive species between Lake Michigan and the Mississippi River Basin. Infrastructure put into place in the CSSC uses a weak electrical current to form a barrier to the passage of fish.

The Illinois Department of Natural Resources and U.S. Army Corps of Engineers (USACE) have worked together since 2002 to develop what is being called the Aquatic Nuisance Species Dispersal Barrier. The barrier project introduces electrical power into the water at an equivalent field strength of one volt per square inch.

Resource managers chose to use an electric barrier for two reasons; the technology is non-lethal to fish and the barrier doesn’t interfere with vessel navigation. An initial demonstration project labeled Barrier I was put into service that used steel cables laid on the bottom of the canal to transmit low-voltage direct current into the water. The next phase of the project called Barrier IIA was recently put into operation. Fish find electrical fields to be uncomfortable and will not swim across them.

The Threat of Invasive Non-Indigenous Species

Waters of Lake Michigan and the Mississippi River Basin are directly connected by the man-made Chicago Sanitary and Ship Canal, which the only shipping link found between them. The project was built in 1900 and involved reversing the flow of the Chicago River. Construction of the canal grew out of concern for protecting the quality of Chicago’s drinking water.

Non-indigenous aquatic species can utilize the Canal to access new habitat and prey on native species or compete for food. Natural resource managers are greatly concerned with the possible introduction of Asian carp into the Great Lakes.

Boating Safely Near the Dispersal Barrier

The U.S. Coast Guard has concerns with the safety of boaters that transit through the electrical barrier. A regulated navigation area (RNA) was established by the agency to insure the safety of mariners that use the CSSC. This special area lies between mile 295.0 and 297.5 of the river. Commercial vessels carrying hazardous cargo are required to use an escort as they pass over the barrier. The Coast Guard is asking all boaters to exercise caution while passing through this area by staying out of the water, closely supervising children and pets, remaining seated in the boat, and wearing a Type I personal flotation device (PFD) while on deck.

Boaters are asked to contact the Coast Guard Marine Safety Unit Chicago with any questions or concerns about the project and its safety at 630.986.2155. The Aquatic Nuisance Species Dispersal Barrier is an unique collaboration of state and federal agencies to protect the environment and insure the safety of boaters in Illinois. The U.S. Army Corps of Engineers maintains the Chicago Fish Barrier Homepage where boaters can learn more about this effort.

The copyright of the article Aquatic Nuisance Species Dispersal Barrier in Green/Clean Boating is owned by Alan Sorum. Permission to republish Aquatic Nuisance Species Dispersal Barrier in print or online must be granted by the author in writing.