During the Fish Passage 2015 conference in June this year, the fish passage project located on the River Tormes at the SSF hydropower plant near Salamanca, Spain, was recognized with the prestigious "Distinguished Fisheries Project in Engineering and Ecohydrology Award 2015" award. This award is proudly presented by the EWRI-AFS Joint Committe on Fisheries, Engineering and Science and recognizes the best international project multidisciplinary approach around the fishways, for collaboration, innovation, education and improvement of ecological value. The award was presented in the 5th World Congress on fishways recently held in Groningen (Netherlands) and is shared with the following affiliations: GEA-ecohydraulics, SSF consortium (town hall and private associates), CHD (Duero River Authority), State Fisheries Section (Castilla y León), Fishermen associations (Cruz de Béjar).
Project Website Link: http://www.gea-ecohidraulica.org/tormes.php
Visit Fish Passage 2015 conference website for more details about the award selection process
The “Salto de San Fernando” hydropower plant is located on the River Tormes (Natura 2000 network), just upstream of the Santa Teresa reservoir (Salamanca, Spain). The structure was built in 2002 and rights are shared between two local villages (Cespedosa de Tormes and Santibáñez de Béjar) and a private society (SSF S.L.). The dam is 13 m high and a pool and weir (with bottom orifice) fish ladder allows potamodromous fish from the Santa Teresa reservoir (Iberian barbel –Luciobarbus bocagei–, Nothern straight-mouth nase –Pseudochondrostoma duriense, IUCN status “vulnerable”– and brown trout –Salmo trutta–) to overcome the obstacle. After construction , several public and non-profit organizations became aware of a problem: Santa Teresa reservoir fish couldn’t reach the spawning areas upstream of the San Fernando dam.
In 2011, the owners contacted the Applied Ecohydraulics research Group of the University of Valladolid to evaluate the problem and research solutions. The fish migration complex is being monitored and has been modified since then. Monitoring consists of daily trapping and counting fish reaching the last pool; fish passage video recording through the orifices and spillways; tagging fish (PIT, T-bar and others) and studying passage metrics (location, entrance, passage time, performance). Public government bodies (local, state and federal) and fishermen associations collaborate actively in the project.
Results have been analyzed as a function of physical and biological variables, including downstream migration to locate fish routes and understand fish behavior. The research has led to identification of passage improvement options which are implemented and assessed in the following migration seasons. An interesting submerged weir and orifice fish ladder was proposed with high slope (15%) and low drop (25 cm), in order to avoid foundation problems and it was tested successfully last year. This overall approach has quintupled fish ladder efficiency and provided a lot of information on Iberian fish behavior and their preferences under different hydraulic conditions. Improvement works cost 116,587 € and research costs were 57,822 € over 3 years. This is a good example of education on fish migration problems and solutions: public engagement through the WFMD 2014 action day; and now supports a national fish pass course for the university and future designers visits; etc.
Photos (c) to Fco. Javier Sanz-Ronda & Sergio Makrakis