Project 2007-2012Realization 2013-2014
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.
The site is screened on two sides by an enclosing timber wall: on the north towards the road and on to the west from adjoining private properties. The southern perimeter facing the river, on the other hand, is open, bounded only by a green hedge. On the eastern front, a timber fence merges into the amenities building, which incorporates the entrance and supporting facilities, while the wall along the northern and western boundaries offers a 200 m long sheltered solarium with recliners. Yet, from all parts of the facility, attention is focused on the bathing pond at the centre of the site. The biological water treatment basins – the non-mechanical “heart” of the baths – are embedded in the sloping landscape on the opposite side of the road. Together with various leisure facilities provided here, they form a recreational area open all year round to the municipal population. In terms of ecological cleaning capacity, the baths are designed to accommodate 2 000 bathers per day.
Herzog & de Meuron, 2014
Located outside Basel, in the valley of the Wiese River, which is a tributary of the Rhine, the Riehen Commune called a competition in 1979 for the purpose of refurbishing its municipal swimming pools, but it took up to the year 2007 for the project to be carried out. In the interim, swimming pool technology had evolved, with old mechanical and chemical water treatment systems giving way to methods which were more respectful towards the environment, based on principles of biological cleansing. These advances were incorporated in the final project. So, for example, the tank of conventional pools, geometric and artificial, was replaced by a natural lake very close to the riverbank. Laid out around this swimming lake, which serves as a functional and symbolic core of the entire complex, is the rest of the program: lockers, changing rooms, and technical areas. Most of this is arranged within a small building which recalls the Badis, the traditional wooden pools situated along the Rhine. With its organic design, the building stretches on to end in a wooden palisade that closes the precinct except on the south border, where it opens to bring in sunlight and offer views of the river. Both the building and the palisade is built with a larch timber structure of asymmetrical porticoes and pieces assembled with simple steel hinges.