Résumé :
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Fish passes are of increasing importance for the restoration of free passage for fish and other aquatic species in rivers as such devices are often the only way to make it possible for aquatic fauna to pass obstacles that block their up-river journey. studies of existing devices have shown that many of them do not function correctly. the present guidelines first refer to the underlying ecological basics and discuss the general requirements that must be understood for sensible application of the complex interdisciplinary matters. these general considerations are followed by technical recommendations and advice for the design and evaluation of fish passes as well as by proposals for choosing their hydraulic dimensions correctly and testing the functioning. fishways can be constructed in a technically utilitarian way or in a manner meant to emulate nature. bypass channels and fish ramps are among the more natural solutions, while the more technical solutions include cnventional pool-type passes, slot passes, fish lifts, hydraulic fish locks and eel ladders.
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