Tuesday, 30 June 2026
PORR has completed the tunnel breakthrough on the ElbX river crossing, marking a key milestone in the construction of the SuedLink electricity transmission project in Germany.
The breakthrough took place on 22 June during work carried out for TenneT Germany and connects the federal states of Schleswig-Holstein and Lower Saxony through a tunnel approximately 5.2 kilometres long beneath the River Elbe.
The crossing forms one of the most important sections of the SuedLink high-voltage direct current (HVDC) transmission corridor, which will transport renewable electricity generated in northern Germany to the country’s southern regions.
According to PORR, the tunnel was excavated using a tunnel boring machine at depths of several dozen metres beneath the river under challenging geological and groundwater conditions.
The company said favourable ground conditions during the final 400 metres of excavation enabled higher advance rates than previously achieved on the project. The tunnel boring machine reached a maximum daily advance of 32.6 metres, while the highest weekly progress totalled 158.7 metres.
Karl-Heinz Strauss, CEO of PORR, said the breakthrough was achieved ahead of the original schedule despite the technical complexity of constructing a tunnel beneath the Elbe.
René Hallbauer, Project Manager for Tunnelling at PORR, said the milestone reflected detailed planning, modern tunnelling technology and close coordination between the project teams.
Following completion of the breakthrough, work will continue with the internal fit-out of the tunnel and installation of its technical systems.
The ElbX crossing extends approximately 5.2 kilometres between Wewelsfleth in Schleswig-Holstein and Wischhafen in Lower Saxony. Once completed, it will carry high-voltage direct current cables beneath the River Elbe as part of the SuedLink transmission system, supporting the delivery of wind-generated electricity from northern Germany to major demand centres in the south.
