319 Naturbad Riehen

The Swiss municipality of Riehen, bordering the city of Basel, lies in the gently widening valley of the River Wiese, near to its confluence with the Rhine. For decades, the local population has yearned for a new public swimming pool to replace the obsolescent baths by the riverbank, with various attempts having failed. After winning a design competition in 1979 and several unrealised projects in the following years, Herzog & de Meuron again started to ponder the options for a new bathing facility. The changed perspectives brought by the intervening years prompted the idea of abandoning the conventional pool concept with its mechanical and chemical water treatment systems in favour of a pool closer to a natural condition with biological filtration. This approach was publicly discussed by the citizens of Riehen and officially approved by a municipal vote. The standard geometric swimming pool transforms into a bathing lake where the technical systems and machine rooms vanish, to be substituted by planted filtering cascades. This concept led to the notion of modelling the natural pool on the local “Badi”, Basel’s traditional wooden Rhine-side baths, which combine a lively atmosphere with a timeless appearance.