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Elvira, B., G. G. Nicola and A. Almodovar (1998). A catalogue of fish passes at dams in Spain. Pages 203-207 in M. Jungwirth, S. Schmutz and S. Weiss, eds. Fish Migration and Fish Bypasses, Fishing News Books, Vienna (Austria).

An inventory of fish passes at Spanish dams was made, and their effectiveness and level of maintenance were estimated. A total of 108 passes were catalogued, 31% of which were constructed after 1990. These passes are placed at weirs and dams of moderate height (1.5 to 25 m). Many of them are located in northern Spain and are mainly devoted to salmonid passage. Thus, 61% of the passes coincide with the occurrence of brown trout Salmo trutta, and 28% with the occurrence of both Atlantic salmon Salmo salar and brown trout. The most common fish pass design is the pool-and-weir (87%), followed by the Denil type (5%). With regard to effectiveness, it was estimated that 58% of surveyed facilities can be passed by target species. As for maintenance status, 61% of the passes are in good condition. A significant result of the survey is that a large majority of the approximate 1100 large dams built in Spain lack fish passes. Likewise, it was confirmed that alternative fish passage facilities, i.e. fish locks, fish lifts or bypass channels, are still absent from Spanish dams.