The Mumbai-Ahmedabad High-Speed Rail (MAHSR) project has achieved a major milestone with the successful breakthrough of a 2.7-kilometre tunnel section. The National High Speed Rail Corporation Limited (NHSRCL) announced this as the first breakthrough in the 21-kilometre tunnel between Bandra-Kurla Complex (BKC), Mumbai, and Shilphata, Thane.
This tunnel is a critical segment of India’s first bullet train corridor. Out of the total 21 km, 16 km will be constructed using Tunnel Boring Machines (TBMs), while the remaining 5 km – especially between Shilphata and Ghansoli – is being built using the New Austrian Tunnelling Method (NATM). The project also includes a 7-km undersea tunnel section beneath Thane Creek, a first-of-its-kind challenge in Indian tunneling history.
To speed up progress, an Additional Driven Intermediate Tunnel (ADIT) was constructed, allowing excavation from both Ghansoli and Shilphata sides simultaneously. So far, around 1.62 km has been excavated from Shilphata, taking the total NATM progress to 4.3 km.
Advanced safety systems have been implemented at the site, including ground settlement markers, piezometers, inclinometers, strain gauges, and biometric access controls to protect surrounding infrastructure and communities.
While the NATM portion has made significant progress, Tunnel Boring Machines for the remaining 16-km stretch are yet to be delivered, though all launch shafts and supporting equipment are ready.
The ₹1.08 lakh crore project is being funded by the Union Government (₹10,000 crore), the states of Gujarat and Maharashtra (₹5,000 crore each), and a low-interest loan from Japan at just 0.1%.
This milestone marks a significant leap forward in India's ambition to introduce high-speed rail infrastructure, promising faster, safer, and more efficient intercity travel in the near future.
