The Chicago Sanitary and Ship Canal Aquatic Nuisance Species Dispersal Barrier
Philip B. Moy, Irwin Polls, and John M. Dettmers
Abstract.—The Chicago Sanitary and Ship Canal is a 50 km-long, man-made canal that connects the Great Lakes and Mississippi River drainages. The canal, which is important for navigation and storm and wastewater drainage, forms an aquatic pathway for nonnative aquatic species to spread between these two major Midwestern ecosystems. Construction of the Chicago Sanitary and Ship Canal aquatic nuisance species dispersal barrier was authorized by the National Invasive Species Act of 1996. The barrier currently consists of a micropulsed DC electric array. A demonstration barrier began operation in April 2002 and is nearing the end of its design life; a larger, longer lasting barrier is now under construction. The demonstration barrier has been effective in repelling radio-tagged common carp Cyprinus carpio and is expected to have similar effectiveness on other large fish. The new more powerful barrier will be more effective in repelling small fish. In the near term, addition of alternative technologies such as acoustic bubble arrays may augment effectiveness of the electric barrier. In the long term, separation of the Lake Michigan and Mississippi River drainages will provide the surest means of preventing the range expansion of aquatic invasive species via this pathway. Funding, authorization and existing waterway uses will continue to challenge development of a fully effective barrier system.