Abstract: A fishway comprising a channel having spaced-apart side walls and an interconnecting bottom wall for conducting a flow of water therethrough, a plurality of longitudinally spaced vortex generators formed on each channel side wall for providing reversing vortices in the flow stream of water along the channel whereby alternately reversing cross-stream water flows and upstream water flows are created to assist fish using the fishway in upstream travel. The vortex generators are provided by uniformly spaced baffles extending alternately from the channel side walls. The channel can be straight or curved in the form, for example, of a helix.