Doka supports expansion of what will become the world’s largest enclosed drinking water reservoir

What may at first appear to be a purely functional structure is part of a highly sensitive supply system: the Neusiedl am Steinfeld drinking water reservoir is currently one of Europe’s largest reservoirs and plays a key role in supplying Vienna with drinking water. The expansion of the site has been underway since December 2024. Once completed, the expanded reservoir will become the world’s largest enclosed drinking water reservoir, setting a new global benchmark for drinking water storage. Large wall areas with heights of up to twelve meters are a defining feature of the construction process. For these wall sections, Doka is using the high-performance framed formwork system Framax Xlife plus.

Slab solution at a height of twelve meters
A precisely coordinated solution is also required for the slab areas. 1,200 m² of DokaXdek tables are being used on a twelve-meter-high supporting construction with the Load-bearing tower Staxo 100. The infill areas around the 70 cm round columns are particularly demanding. Using DokaXdek suspension clamps in combination with H20 beams, these areas can be formed efficiently. This reduces the need for additional supporting measures in the infill areas – and, with more than 100 columns, significantly lowers both labor and material requirements.

Safe access, stable working areas
Safety plays a central role in an infrastructure project of this scale – particularly for a public client such as the City of Vienna. On the twelve-meter-high walls, the Xsafe plus platform system provides safe working platforms and integrated access directly on the formwork. For the reinforcement work, Ringlock provides double-width scaffolding that gives crews more space and stability.

“At this challenging working height, we need sufficient space and secure footing for the reinforcement work. The double-width Ringlock configuration next to the formwork gives the crew more freedom of movement and creates a stable working base,” says Paul Schein, site foreman at Gebrüder Haider & Co Hoch- u. Tiefbau GmbH.

More storage capacity for a growing metropolis
The expansion is part of the “Wiener Wasser 2050” strategy, through which Vienna is adapting its drinking water infrastructure to population growth and climate change. The existing reservoir consists of four water chambers and holds around 600 million liters of water. In the coming years, four additional chambers will be built, and the existing chambers will be refurbished. Once completed, the storage volume will amount to around one billion liters, or one million cubic meters.

This makes the project more than a concrete structure: it strengthens Vienna’s long-term water security and shows how reliable formwork and scaffolding solutions contribute to the safe delivery of essential infrastructure.