Fishway Entrance Gate Orientation Effect on Upstream Migrating Adult American Shad (Alosa Sapidissima)

Increasing fishway attraction efficiency and entry rates is recognized as an important research need within fish passage engineering.  The design of a properly functioning entrance relies on knowledge of the target species behavior and swimming performance.  Nevertheless, a paucity of information exists regarding the correlation between a number of entranceway design parameters and the behavioral response of common target species (e.g. American shad).   Typically, a fishway entrance consists of a fully submerged hydraulic control (e.g. flap gate) located at the downstream end of a rectangular channel that leads fish to the main body of the fishway (e.g. lift, pool-and-weir).  Changes to the hydraulic control design and tailwater levels can influence the hydraulics (e.g. entrance jet velocity, flow pattern) and thus attraction and entry performance.  The aim of this research is to understand how American shad respond to a variety of fishway entrance gate orientations (i.e. angle of the gate to the channel floor) and hydraulic conditions (e.g. water surface elevation, velocity) both upstream and downstream of the gate.  The results will provide guidance on methods to improve fishway attraction and entry rates, and overall fish passage structure performance, to numerous state and federal resource agencies and the hydropower industry.