River Rhine Continuity, extracted from a report by Regiowasser & AK Wasser im BBU
The Rhine was once the largest salmon-bearing river in Europe. 100 years ago, there were millions of salmon (Salmo salar) in the Rhine and its tributaries, all the way to the Swiss Alps. The salmon hatched in freshwater, then travelled to the ocean in Greenland’s waters, only to return to their birthplace in the mountain’s rivers several years later in order to reproduce.
In the 1950s, salmon gradually disappeared from the Rhine River basin. A reintroduction plan initiated in 1991 by the International Commission for the Protection of the Rhine (ICPR) as part of their international programme has been very successful. Salmon now swim upstream once again from Rotterdam to the Iffezheim dam (30 kilometres from Karlsruhe), as well as in the Rhine’s tributaries (particularly the Sieg).
Ever since fishways were added to the Iffezheim and Gambsheim hydroelectric dams, salmon have been able to swim upstream again all the way to Strasbourg, where their journey ends, as 8 more French dams owned by “Electricité de France” block their migratory path.
If these dams became passable, salmon could once again populate both new Black Forest tributaries and their original spawning beds above Basel in Switzerland, as many of the dams in the Black Forest and in Switzerland have already been equipped with fishways.