Rathaus station

U2 construction site: a look into the depths of the city

The new doors have now arrived. They are now being tested.

(Bild: Zwefo)

The reopening of the U2 station at Rathaus has been delayed - longer than originally planned. But we had the opportunity to take a look behind the scenes of the major construction site. 

The news that the U2 extension has once again been delayed has caused a stir among public transport users. One of the main reasons for the delay is the automatic doors, some of which were damaged during the construction work. To gain a deeper understanding of the difficulties, the "Krone" was given the opportunity to take a tour of the currently closed Rathaus subway station and explore the complex world behind the construction fences.

The construction site at Rathaus station is far more than just an ordinary building project. Work is being carried out here at the intersection of two future transport lines - the U2 and the new U5. 

The new tracks at Rathaus station.

(Bild: Zwefo)

One of the biggest hurdles was dealing with the automatic platform screen doors, which are essential for the fully automatic operation of the new subway lines. During the construction work, layers of water were encountered in the Rathaus area. These water ingresses into the shafts and tunnel tubes made the construction work considerably more difficult and in some cases led to unexpected earth movements. These shifts in the ground in turn caused damage to the newly installed doors.

Although we are carrying out test drillings, we cannot drill through the whole of Vienna.

Michael Freidl, Projektleiter

The affected doors had to be replaced, but even that was easier said than done. The doors are manufactured in France and the production company was very busy with preparations for the Olympic Games. These international delays caused additional waiting times, which further disrupted the construction schedule. But the difficulties did not end with the delivery: the transportation of the heavy, delicate doors also posed a logistical challenge, as the special cranes and access points originally planned had been dismantled or closed in the meantime. Wiener Linien is still keeping quiet about the additional costs, "the final invoice will be issued after the end of construction", they say. In total, the project costs will have to be increased by 15 percent or 300 million euros.

If the automatic door system fails, manual intervention is possible.

(Bild: Zwefo)

Finally, the new doors have been installed and wired, but the work is far from finished. Extensive tests have to be carried out before the U2 can go back into operation. 72 test runs are required per station to ensure the safety and functionality of the doors. With eight stations affected, this results in an enormous number of test runs, which together contribute significantly to the delay. And only once these tests have been successfully completed can the doors be finally approved by an independent expert.

"It is an extremely complex construction site, as work is being carried out on several levels and sections at the same time," explains Michael Freidl, Project Manager for the U2 main line. 

View of the lower-lying construction site, along which the U2 will run in future.

(Bild: Zwefo)

During our tour, we had an impressive view into the depths of the excavation pit. Intensive work is being carried out here on the new U2 line and the progress is visible. The construction site is a place of constant activity, where people are working tirelessly to drive the project forward. "We are doing everything we can to make progress as quickly as possible, but unexpected problems can always hold us up and cost us time," says Freidl.