Gigantic construction project: Tunnel under the Vienna River reaches Vienna!

Gigantic construction project: Tunnel under the Vienna River reaches Vienna!

On the night of Tuesday to Wednesday, March 12, 2025, an impressive tunnel boring machine, also called a “super drill,” arrived in Vienna. This mammoth project for the new Wiental Canal will be the city's largest water protection measure by 2028. The drill, which will cross six districts under the Vienna River, has an external diameter of almost four meters and will help relieve pressure on sewer networks during times of heavy rain and protect the Vienna River from contamination. Climate City Councilor Jürgen Czernohorszky (SPÖ) confirmed this in his announcements, which underline both technological and ecological progress.

The impressive drilling machine was manufactured in several transportable units and had to be transported to Vienna over a distance of around 800 kilometers. Three special transports were required right from the start because the parts exceeded the road traffic regulations. The logistical challenge was appreciated under the eyes of experts, such as that of district leader Wilfried Zankl. “Designing and drilling a sewer tunnel across the city is a huge challenge,” added Czernohorszky, as engineers overcome the challenge with precision and skill. The drilling machine will be assembled in an underground tunnel and should be completed by the end of March before drilling begins in mid-April.

Technical details and schedule

The project extends over several years with a total investment of around 270 million euros. The tunnel will be more than 8.6 kilometers long and include 43 connections to the existing sewer network. The western section is scheduled to last from spring 2025 to summer 2026, while the eastern section will be completed from autumn 2026 to spring 2027. According to Czernohorszky, the initial work has gone without any accidents or complications, which contributes to the optimistic mood surrounding the project. For the people of Vienna, this major project not only brings a long-term investment in infrastructure, but also the certainty that the city is better prepared for future extreme weather events, as reported by OTS.at proven.