European Nature-Like Bypass Channels in Review

Nature-like fishways are popularly applied in Europe for improving the passage of migratory and resident species. The design philosophy for these fishways is ecologically minded, aiming to achieve a good fit with the specific riverine environment they are constructed in. Yet the efficiency of this type of facilities is still debated. This paper is an updated review of recent installations and efforts  to evaluate how effectively they serve for passage and as an impact compensation measure.  We collected the information from literature, visiting case studies and communicating with colleagues active in this area. The paper will present key morphological and hydraulic parameters of the fishways such as slope, head loss design flows as well as target species. The goal is to supply designers and people faced with fish passage decisions with illustrations of the many nature-like fishways already constructed to encourage this type of innovative thinking and nature-like design approach, when feasible.