The proposed adjustable hydraulic structure (AHS) has been uniquely designed to maintain blockage to the upstream migration of sea lamprey. It would utilize inflatable bladders to raise and lower steel gates to maintain sea lamprey blockage criteria established  by the Great Lakes Fisheries Commission. During times when the gates must be lowered to accommodate high flow events, the AHS relies on faster water velocities to prevent upstream sea lamprey migration.

The operational functionality of the AHS would be able to achieve multiple goals, including flood conveyance, sea lamprey control, maintaining target upstream water levels, and potentially allowing upstream fish passage during periods when sea lamprey are not in the river.