Construction begins on the A7 tunnel at Altona

Symbolic groundbreaking with representatives from politics in front of the future tunnel entrance.

Bridge demolition during full closure of the A7 in the area of Hamburg-Altona.

Visualization of the Hamburg “Deckel” and the A7 that runs beneath it.

A few days ago work officially began on construction of Hamburg’s third “covered interstate”, forming a tunnel for the A7 highway in the city’s Altona district. This ushers in the third and final phase of one of the Hanseatic city’s most important infrastructure projects: With the current construction work between the exits at Hamburg-Othmarschen and Volkspark, which follows on from the sections covered over in Stellingen and Schnelsen, the third and final noise-protection tunnel on the A7 is taking shape alongside an increase in lanes from six to eight.

By the end of March, three bridge structures spanning the highway had already been semi-demolished in a concerted effort lasting just 79 hours. This is a preliminary measure that will now be followed by four primary construction phases running through 2028 that will involve extensive and intricately interwoven construction activities – all planned to limit disruption to traffic as much as possible. The goal makes it all worthwhile, however: The tunnel is both effective noise protection and an urban planning opportunity at the same time. The areas of the city that have for decades been sliced through by a thoroughfare can now merge again, connected by new green spaces.

WTM Engineers has already worked on the A7 tunnel at Schnelsen, and in the Altona section collaborated with engineering firm Grassl to develop the plans for the 2,230-meter-long tunnel, the 900-meter noise protection walls, and a number of temporary measures and construction aids.