Thane-Borivali twin tunnel project gains pace as first TBM ‘Nayak’ set for launch

Tunnel boring machine ‘Nayak’ at the project site in Manpada, Thane. Pics/Ashish Raje

The Thane-Borivli twin tunnel project is set to gain momentum with the launch of its first Tunnel Boring Machine (TBM) ‘Nayak' on Monday. The 11.84-km underground corridor is being implemented by Mumbai Metropolitan Region Development Authority (MMRDA)and executed by Megha Engineering & Infrastructures Ltd. mid-day got an exclusive look at the preparations on site.

Team behind TBMs ‘Arjuna' and ‘Nayak', which are being launched in phases at Manpada, Thane, on Friday

Four of the largest TBMs used in Mumbai will be deployed, each equipped with a 13.2-metre cutterhead. These machines will excavate twin three-lane tunnels beneath Sanjay Gandhi National Park, connecting Ekta Nagar in Borivali to Manpada in Thane at a depth of up to 23 metres. Cross-passages will be constructed every 300 metres for evacuation and maintenance.

Tunnel boring machine ‘Nayak', which is set to begin tunnelling for the Thane-Borivli twin tunnel project

Authorities have planned measures to minimise disruption during construction. A dedicated corridor will be used for debris transport so that dumpers do not enter residential areas. Traffic will be regulated with limited vehicle movement, round-the-clock monitoring, and systems to control dust
and noise.

An inside view of tunnel boring machine ‘Nayak'

With more TBMs set to be deployed, the project is expected to significantly improve connectivity between Mumbai's western suburbs and Thane while maintaining a strong focus on safety and environmental safeguards.

Tunnel boring machine ‘Nayak' positioned for launch at the Thane-Borivli twin tunnel project site

11.84 km
Length of underground corridor

Work planned for monsoon

Authorities have made provisions to ensure work continues during the monsoon. Dewatering pumps will be installed across the site to quickly drain accumulated rainwater.

Round-the-clock work
Tunnelling will continue 24 hours a day, with around 300 workers deployed at any given time.

Minimal disturbance to park
As tunnelling will pass beneath the national park, methods are being used to keep vibrations negligible and avoid disturbing wildlife movement.

Real-time monitoring
A central control room will oversee TBM operations, supported by CCTV and live camera feeds for continuous monitoring.

Project snapshot
Thane-Borivli twin tunnel project
. First TBM ‘Nayak' set for launch
. Part of an 11.84-km twin tunnel corridor
. Project by MMRDA, executed by MEIL
. TBMs manufactured by Herrenknecht AG

Key features

. Four mega TBMs will be deployed, each with cutterhead measuring 13.2 metres in diameter. The twin tunnels span 11.8 km. There will be three lanes in each tunnel that links Ekta Nagar to Manpada. They have a maximum depth of 23 metres.

TBM rollout plan

. TBM "Nayak" to launch in the coming days
. Second TBM "Arjuna" expected in about a month
. Two more TBMs to be deployed from the Borivli side

Traffic management

. Dedicated corridor for dumpers, avoiding residential roads
. Barricaded roads for residents
. Maximum of eight dumpers per hour, in regulated batches
. 24x7 traffic wardens and signal systems