Barges and the Electric Dispersal Barrier, Chicago Sanitary and Ship Canal

Several electrical barriers are operating in the Chicago Sanitary and Shipping Canal to block the movement of Aquatic Nuisance Species between the Great Lakes and Mississippi River Basins. These barriers are unique, as compared to other electrical barriers of the world, in that they operate in a large canal used for navigation by large commercial barges. The overarching objective of the study was to determine the potential for barges to entrain fish past the barrier as they passed from the Mississippi River Basin to the Great Lakes Basin. We placed either tethered or caged Gizzard shad (Dorosoma cepedianum), in front of moving barges, or in junction spaces around barges, as and before barges traversed the barrier system. A variety of barge configurations and navigation methods were tested. Fish were entrained past the barrier, to varying degrees, in every configuration and navigation method attempted. Despite these troublesome findings, the study results do shed light on pragmatic management recommendations that can limit the risk of fish entrainment.