Zürich–Winterthur expansion due in 2037
SWITZERLAND: Preliminary works have begun on the 9 km Brüttener Tunnel, the centrepiece of a project to expand the Zürich–Winterthur main line in northeastern Switzerland to four tracks. Swiss Federal Railways (SBB) expects the project to be completed in 2037.
The start of preliminary works moves the project from approval into construction on one of the most important capacity bottlenecks on the Swiss network. SBB said the construction programme had now been fixed together with the appointed construction firms.
That clarifies how the project will be delivered, not just when it is due to finish. Preparatory works are starting first, with tunnel boring due to follow later in the programme.
Brüttener Tunnel anchors phased capacity build-out
The Brüttener Tunnel is the central element in a broader scheme to expand the Zürich–Winterthur corridor to four tracks. The route is one of the busiest in Switzerland and a key constraint on network capacity in the northeast of the country.
SBB has set out a phased build-out rather than a single end-point opening. Station upgrades are due to enter service in stages before the tunnel itself opens.
Tunnel boring is scheduled to start in 2029. First trains are due to run through the Brüttener Tunnel at the end of 2037.
This matters because the project is not just about a new tunnel. It is about releasing capacity across the full corridor through a sequence of civil works, station upgrades and final commissioning.