The “Pont Neuf” of Aarau

The new Aare bridge, designed by the Basel office Christ & Gantenbein in collaboration with the planning engineers WMM-Ingenieure, Henauer Gugler AG and August + Margrith Künzel Landschaftsarchitekten, is not only an important access point in the town of 20,000 inhabitants in the Swiss canton of Aargau.

The bridge crosses the Aare and connects the old town on the south side with the Scheibenschachen district on the north side. Its special design makes it a new landmark of the city, which many people are currently discovering for themselves. Artistic cyclists, for example, are practising their acrobatic exercises underneath the bridge in the piers with their elliptical, expressive openings. The project name of the Aare bridge is “Pont Neuf” and many thousands of cars and hundreds of buses cross it every day to cross the river.

The design of the “Pont Neuf” follows the traditional type of segmental arch bridge. It is characterized by large clear spans. The entire bridge body has no joints and looks like a huge monolithic sculpture. The classic massive piers, such as the previous bridge from the middle of the 20th century, have been transformed into more delicate, expressive forms. The masses of the piers dissolve into a series of elliptical recesses, as can be clearly seen when crossing underneath the bridge. These inner contours are clearly visible from the promenade, which was also redesigned as part of the construction work. With a length of 119 meters and a width of 17.5 meters, the bridge offers two lanes, sidewalks on both sides and cycle paths. Where the bridge spans the riverside path, large openings offer a view of and across the water. Great importance was attached to the design of the concrete surface: The precisely structured exposed concrete follows an arrangement that gives the bridge an almost textile look and is reminiscent of a curtain from a distance.

While traffic is moving on the bridge, the existing riverside promenades are being reinterpreted and upgraded: On the Old Town side, a spacious, urban promenade is being created with a square-like recreation area and shady trees. On the northern bank, the bridge will be accompanied by green flower meadows and natural riverbank vegetation. The aim here is to significantly increase the quality of stay. The “Pont Neuf” was commissioned by the canton of Aargau and the city of Aarau. According to various media reports, the costs amount to around 40 million Swiss francs. The bridge architecture was designed by a five-person team from Christ & Gantenbein, including Emanuel Christ, Christoph Gantenbein, Mona Farag, Tabea Lachenmann and Jean Wagner.

The competition to build a new bridge was launched in 2010 to replace a concrete bridge built in 1949. Bridge construction has a long tradition at this location: since Roman times, there has been a bridge over the Aare from the historic town center over the Zollrain to the north towards the Jura. It has been replaced several times by new structures. A chain bridge from 1848 and the concrete bridge from 1949 are documented. The bridge is an important link in the city traffic. It is the gateway to Aarau. An auxiliary bridge had to be erected for the duration of the construction work to prevent traffic from sliding into chaotic tracks. It was erected and dismantled like a normal bridge.

The “Pont Neuf” is the link to the urban fabric and at the same time part of the landscape along the Aare. Its calm, balanced structure embeds it in the river landscape, and it also acts as a mediating transition to the historic old town. The seamless transformation of the bridge body into the embankment walls connects the bridge with the river space. The “Pont Neuf” is a technically optimized, modern concrete structure and at the same time has the appearance of a traditional building. Its construction and design refer to the solidity of the many historic stone buildings in Aarau, including the medieval houses along the town wall, the nearby pillars, retaining walls, ramps and bank reinforcements. The concrete is lightly colored to match the urban surroundings. With the many hollow bodies in the piers of the “Pont Neuf”, which make the arched reinforced concrete construction possible, concrete was used sparingly. The five arches with different spans rest partly on the caissons of the old bridge in the riverbed, which could thus be reused. All bridge elements support the load transfer in order to ensure the most sustainable, durable construction possible.