The B1M

Switzerland’s $2BN Tunnel U-Turn

Switzerland is constructing a second Gotthard road tunnel to replace the aging 1980s tube and allow a full renovation of the original without halting the vital A2 corridor. The $2 billion project, slated for completion by 2030, runs parallel to the existing tunnel and will carry traffic in one direction while the refurbished tube handles the opposite flow, preserving a key north‑south European link. The twin tunnel boring machines, Alisandra from the north and Paulina from the south, have been advancing simultaneously. In June, Paulina hit a 400‑meter shear zone of fractured rock, forcing the machine to stop and adding roughly 20 million Swiss francs to the budget. Engineers responded by switching to conventional drill‑and‑blast in that segment and accelerating other work to keep the overall schedule on track. The project showcases innovative practices: underground concrete plants reduce surface footprint in avalanche‑prone areas, and about half of the 7.5 million tonnes of excavated rock is recycled into concrete, road surfacing, or habitat creation in Lake Lucerne. Additionally, a new high‑voltage power line will run beneath the tunnel, replacing unsightly pylons on the Gotthard Pass. By delivering a second tube, Switzerland safeguards uninterrupted trans‑Alpine traffic, enhances safety with separate directional lanes, and meets constitutional limits that prevent capacity expansion. The tunnel’s environmental measures and resilient design set a benchmark for large‑scale infrastructure in geologically complex regions.