Mumbai-Ahmedabad Bullet Train: Tunnel Breakthrough!

The National High Speed Rail Corporation Limited (NHSRCL) has achieved a major milestone in the Mumbai-Ahmedabad bullet train project with the completion of a 2.7-km continuous tunnel section using the New Austrian Tunnelling Method (NATM).

This breakthrough, accomplished on July 9, 2025, marks a key achievement in constructing the 21-km-long tunnel between Mumbai’s Bandra-Kurla Complex (BKC) and Shilphata in Thane—one of the most complex segments of the high-speed rail corridor. The tunnel includes a distinctive 7-km undersea portion beneath Thane Creek.

Of the total 21 km, 16 km will be excavated using Tunnel Boring Machines (TBMs), while the remaining 5 km—mainly between Shilphata and Ghansoli—will be constructed using NATM. To accelerate work in the NATM section, an Additional Driven Intermediate Tunnel (ADIT) was constructed, enabling simultaneous excavation from both Shilphata and Ghansoli ends.

So far, 1.62 km has been excavated from the Shilphata side, with total NATM progress reaching 4.3 km. NHSRCL has deployed a comprehensive suite of safety measures, including ground settlement markers, piezometers, inclinometers, strain gauges, and biometric access systems, to ensure the highest standards of safety and precision during construction.

News by Rahul Yelligetti.