Tunnelling accelerates under SGNP for Goregaon-Mulund link road
Twin tunnels for the Goregaon-Mulund Link Road are being bored under Sanjay Gandhi National Park using two giant tunnel boring machines.
Work on the underground tunnel for the Goregaon-Mulund Link Road (GMLR) project, taken up to speed up commuting for Mumbaikars, has now picked up significant pace. Construction of the twin tunnels passing under Sanjay Gandhi National Park is underway on a war footing with the help of two massive tunnel boring machines (TBMs) named Tulsi and Vihar.
The project is being carried out under GMLR Phase 3(B), with twin tunnels of 5.30 kilometres each being built using tunnel boring machines under Sanjay Gandhi National Park, between Dadasaheb Phalke Chitranagari in Goregaon (East) and Amar Nagar in Mulund (West). Each tunnel will have three lanes. The first tunnel boring machine, Tulsi, was commissioned on August 17, 2026. So far it has completed 64 metres of excavation, while assembly of the second machine, Vihar, is 92 percent complete.
Tunnelling by Tulsi is continuing steadily, and work on installing the ring-shaped segments, a key component of tunnel construction, is also progressing rapidly. During the 64 metres excavated so far, 27 permanent ring segments and 2 temporary ring segments have been installed with the help of Tulsi.
The twin underground tunnels are being built between Dadasaheb Phalke Chitranagari and Khindipada in Mulund, running parallel to each other, each 4.70 kilometres long. The diameter of these parallel tunnels is generally 14.20 metres, but within the Sanjay Gandhi National Park sanctuary area it is 13 metres.
The Tulsi tunnel boring machine is a single-shield earth pressure balance (EPB) hard rock type machine, with a cutter diameter of 14.49 metres and a total length of 83 metres. This includes a 22-metre-long shield section and a 61-metre-long, three-storey back-up gantry. The machine is fitted with a fully automated muck handling system, including a 340-metre-long conveyor system, cross conveyor and stacker conveyor. This allows muck to be transported efficiently even in challenging geological conditions, making the work safer and more productive.
While Tulsi continues excavating one tunnel, assembly of the second machine, Vihar, is 92 percent complete. Once the entire machine is set up at the project site, a Site Acceptance Test (SAT) will begin from October 13, 2026, to verify its efficiency, safety and the coordinated functioning of all systems. Once all technical tests are completed as per the set standards, actual excavation of the second tunnel will begin from October 22, 2026.
