Breakthrough has been achieved in 4 of the total 8 mountain tunnels on the 508-Km Mumbai-Ahmedabad Bullet Train corridor, while excavation work is progressing on the remaining four, according to National High Speed Rail Corporation Limited (NHSRCL).
NHSRCL is the implementing agency for the high-speed rail corridor.
Of the total 8 mountain tunnels, 7 are located in Palghar district of Maharashtra and 1 is located in Valsad district of Gujarat.
The latest breakthrough was achieved in MT-07 at Ambesari village in Dahanu taluka of Palghar district on 1 June.
The tunnel is 417 metres long and 14.4 metres wide, and has been designed to accommodate both up and down tracks of the bullet train corridor.
Before this, breakthrough had been achieved in MT-08, MT-06 and MT-05. MT-08, measuring 350 metres, recorded breakthrough on 5 October 2023.
Read also: Chennai Metro records 90.15 lakh passengers in May; peak daily ridership crosses 3.45 lakh
MT-06, measuring 454 metres, achieved breakthrough on 3 February 2026, while MT-05, measuring 1.5 Km, achieved breakthrough on 2 January 2026.
Among the remaining tunnels, MT-04 has achieved nearly 60 per cent progress, while MT-03 has crossed 80 per cent excavation progress. Work on MT-02 and MT-01 is also progressing steadily, according to NHSRCL.
NHSRCL said the excavation of MT-07 was carried out from both ends using the controlled drilling and blasting method.
Advanced monitoring systems and geotechnical instruments were deployed during the work to ensure structural stability and safety.
Real-time monitoring systems, including Surface Settlement Points, 3D targets, strain gauges and seismographs, were installed to monitor vibrations, tunnel behaviour and nearby structures during excavation.
The agency said safety measures inside the tunnel included ventilation systems, fire safety measures, controlled access arrangements and continuous geotechnical monitoring.
With the excavation of MT-07, three mountain tunnels have been excavated in Maharashtra within the last five months.
NHSRCL said all three mountain tunnels between Vapi and Boisar bullet train stations have now been excavated.
This stretch includes MT-08, MT-07 and MT-06 and passes through an important industrial region between Boisar in Maharashtra and Vapi in Gujarat.
