Thane-Borivali Twin Tunnel: Infrastructure Update

The Thane-Borivali Twin Tunnel, one of Mumbai Metropolitan Region's most closely watched infrastructure projects, has moved from approvals to active excavation. Tunnelling work has commenced for the 11.84-km Thane–Borivali Twin Tunnel, set to be India's longest urban road tunnel, with the tunnel boring machine 'Nayak' launched by Chief Minister Devendra Fadnavis. According to MMRDA's own project tracker, TBM-01 'Nayak' completed its site acceptance test on 26.02.2026 and was launched in the presence of the Chief Minister and Deputy Chief Ministers on 07.04.2026. A second machine is close behind: TBM-02 'Arjuna' completed its site acceptance test on 25.06.2026 and is now ready for its initial drive, while TBM-03 completed its factory acceptance test on 29.05.2026 in Chennai and is ready for dispatch to the Borivali site.

On the ground, work is progressing across both ends of the alignment. At the Borivali side, casting yard setup is currently in progress and piling activity has commenced at the launching shaft area. MMRDA's latest disclosure puts physical progress of the project at 13.13% till July 2026, with financial progress at 12.86% till June 2026. Land-related hurdles are also clearing: most land acquisition in Thane has been completed, while rehabilitation of project-affected persons in Borivali is currently underway.

The scale of the project explains why it has drawn national attention. The twin-tube road tunnel links Ghodbunder Road in Thane with the Western Express Highway in Borivali, running about 11.84 km, with a substantial section passing underground beneath Sanjay Gandhi National Park. Once complete, it will be a genuine engineering first for the country — it is considered the first instance of tunnels being dug under an environmentally protected area anywhere in India. Each bore is generously sized: the two tunnels have a diameter of 12.2 metres each, span roughly 10.25 km, carry two lanes plus an emergency lane, and include a cross-connection lane every 300 metres.

For commuters, the payoff is significant time savings. Currently it takes 1 to 1.5 hours to travel the 23 km distance between Thane and Borivali via Ghodbunder Road; once the tunnel is operational, this journey is expected to take just 15 minutes. Chief Minister Fadnavis reiterated this at the TBM launch event, noting the tunnel would compress a route that presently takes about 2 to 5 hours over 23 kilometres into just 11.84 km, cutting travel to 15 minutes. He also confirmed a firm delivery target: 'Our plan is to complete this by May 2028'.

Safety and environmental safeguards have been built into the design given the sensitive alignment. The tunnels will be equipped with advanced ventilation systems, firefighting infrastructure, smoke detectors, and LED signboards. At the launch event, the Chief Minister praised MMRDA's design, calling the tunnels among the most advanced with modern firefighting, ventilation, and signage systems, and confirmed that all necessary permissions have been received. The project has not been without scrutiny — an ecological survey identified 18 highly protected species along the alignment, and a 2024 report noted environmentalists raising concerns over biodiversity, aquifers, and geology — but construction has continued under the approvals granted by wildlife authorities.

Why does this matter for homebuyers? The Ghodbunder Road corridor in Thane, long valued for larger homes and integrated townships at relatively accessible price points, stands to benefit directly once the tunnel opens. Ghodbunder Road offers larger homes, integrated townships, and lifestyle amenities at comparatively attractive price points, and thousands of professionals commute daily between Thane and business districts in Western Mumbai. As connectivity improves, the corridor is expected to see continued interest from buyers who currently trade off affordability against access to Western Suburb job hubs. Puravankara has an established presence along this stretch through its Ghodbunder Road residential developments, positioning existing and prospective homeowners there to benefit from the eventual drop in commute times to Borivali and the Western Express Highway corridor.

With excavation now underway on both ends and a stated 2028 completion target, the Thane-Borivali Twin Tunnel has moved from a paper plan into visible construction. Homebuyers evaluating Ghodbunder Road or the western Thane belt should track physical progress milestones each quarter, since infrastructure delivery timelines in the MMR often shift, but current momentum — twin TBMs mobilised and land acquisition largely resolved — suggests the project is past its most uncertain phase.