Project Profile: Zurich Durchmesserlinie (DML)

The Zurich Durchmesserlinie (DML) is a landmark 9.6 km rail corridor developed to resolve severe capacity limitations at Zurich Hauptbahnhof, Switzerland’s busiest railway station. By constructing a new east-west tunnel and underground through-station, the project fundamentally re-engineered Zurich’s rail network, increasing throughput for both S-Bahn and long-distance services. This profile details the engineering specifications, technological integrations, and strategic impact of this critical infrastructure upgrade.

Technical Specifications

The core of the DML project is the 4.8 km twin-bore Weinberg Tunnel, which provides a direct subterranean link beneath Zurich’s city center. This tunnel connects to the new Löwenstrasse station, an underground four-platform hub constructed 16 meters below the existing tracks of Zurich Hauptbahnhof, effectively doubling the station’s through-traffic capacity. The project’s western approach is facilitated by two major viaducts: the 1,156-meter Letzigrabenbrücke and the 394-meter Kohlendreieckbrücke, which integrate the new line with the existing network towards Altstetten.

To support the increased traffic flow, a comprehensive modernization of the Zurich S-Bahn’s rolling stock was undertaken. The fleet was expanded with high-capacity double-deck Electric Multiple Units (EMUs), including 60 Siemens RABe 514 trains and 50 six-car double-deck EMUs from Stadler Rail. These modern units enhance passenger capacity, improve comfort, and increase operational reliability. The entire DML route is equipped with the European Rail Traffic Management System (ERTMS) Level 2, an advanced cab-signaling system that eliminates the need for traditional lineside signals, allowing for higher train frequencies, increased speeds, and enhanced safety. The tunnel is also fitted with nine emergency access and escape points to ensure passenger safety and provide maintenance access.

Key Takeaways

• Bottleneck Resolution: The project successfully transformed Zurich Hauptbahnhof from a congested terminus into a high-capacity through-station, significantly improving punctuality and increasing train throughput for the entire Swiss network.
• Technological Integration: By implementing ERTMS Level 2 signaling and deploying a new generation of high-capacity rolling stock, the DML set a new standard for operational efficiency and safety in urban rail transport.
• Urban Infrastructure Benchmark: The DML serves as a global model for resolving urban rail congestion through ambitious tunneling, station construction, and effective stakeholder management, demonstrating long-term investment in sustainable public transit.

Frequently Asked Questions (FAQ)

When did the Zurich Durchmesserlinie open?

The Zurich Durchmesserlinie was opened in two main phases. The first phase, for S-Bahn services through the new Löwenstrasse station, became operational in June 2014. The second phase, accommodating long-distance trains, was completed and opened in December 2015.

Who built the Zurich Durchmesserlinie?

The project was led by the Swiss Federal Railways (SBB). Its construction involved a consortium of leading engineering, manufacturing, and technology firms, including Siemens and Stadler Rail for rolling stock, COMLAB for tunnel radio systems, and various civil engineering and planning companies like EBP and Amstein + Walthert.