This book offers a comprehensive review of current systems for fish protection and downstream migration. It offers the first systematic description of the currently available technologies for fish protection at hydropower intakes, including accurate and timely data collected by the authors and other researchers. It describes how to design and test them in agreement with the guidelines established from the EU Water Framework Directive. The book includes important information about fish biology, with a special focus on swimming and migration mechanisms. It offers a robust bridge between concepts in applied ecology and civil hydraulic engineering, thus providing biologists and hydraulic engineers with an authoritative reference guide to both the theory and practice of fish protection. It is also of interest for planners, public authorities as well as environmental consultants

International Conference on Fish Migration and Bypass Channels held in Vienna in September 1996. It covers the range of fish pass technologies currently in use throughout the world and attempts to develop a wider, more ecological perspective on this formerly engineering-orientated discipline. Emphasis is placed on enhancing an understanding of fish migration behaviour, and achieving optimum design to meet the behavioural requirements of all known migratory species. Additional attention is paid to comparing the European trend towards constructing nature-like bypass channels with the highly technical solutions dominant in North America.

The success of fish migration through culverts is dependent on the swimming ability of the fish and the hydraulic conditions of the culvert. Properly designed and constructed culverts can minimize the impact on fish passage. Because culverts are typically more economical than bridges, it is appropriate to evaluate when to use culverts and to predict the effects of such culvert installations. During the consideration of alternatives for structures for fish passage, culverts should not be automatically eliminated. This publication has tried to examine the aspects of culvert design and operation relative to the existing information that has been published in previous studies. Ideally, a culvert installation should not change the conditions that existed prior to that installation. This means that the cross-sectional area should not be restricted by the culvert, the slope should not change, and the roughness coefficients should remain the same. Any change in these conditions will result in a velocity change which could alter the sediment transportation capacity of the stream. A truly successful culvert design would include matching the velocities of the fish's swimming zone in the culvert to the swimming capacity of the design fish. Unfortunately, not enough research has been completed to make this an acceptable criterion of culvert design. This approach is preferred because it is easier to reduce the velocities in the swimming zone by increasing the boundary roughness than it is to reduce the mean velocity of the entire culvert. This publication contains some relatively simple guidelines which can reduce the installation problems of culverts in streams containing migrating fish when combined with the expertise of an experience fish biologist, engineer, and hydrologist.