07 October,2025 07:52 AM IST | Mumbai | Ranjeet Jadhav
The twin tunnel that will pass under SGNP will feature two parallel tubes, each with two lanes and an emergency lane. File pic/Satej Shinde
Work on the ambitious Thane-Borivli twin-tube tunnel is finally set to gather pace, with construction expected to begin this December beneath the Sanjay Gandhi National Park (SGNP). Estimated at Rs 16,600 crore, the project will directly link the Western Express Highway in Borivli with the Eastern Express Highway via Ghodbunder Road, slashing travel time between the eastern and western suburbs.
A senior Mumbai Metropolitan Region Development Authority (MMRDA) official said, "Work on the Thane-Borivli tunnel has commenced, and we expect to lower the tunnel boring machine (TBM) by the end of this year. This will be the largest tunnel constructed using a TBM anywhere." According to MMRDA sources, the project has a three-year deadline, with strict safety protocols in place.
Project details
The tunnel will stretch 11.8 km, including 10.25 km of tunnel and 1.55 km of approach road. It will feature two parallel tubes, each with two lanes and an emergency lane, and cross-passages every 300 metres. The outer diameter of each tunnel will be 13.05 m.
Three-package execution
Package 1: 5.75 km tunnel on the Borivli side
Package 2: 6.05 km tunnel on the Thane side
Package 3: Electrical and mechanical systems, including ventilation, fire safety, and drainage
Cleaner, faster, greener
The tunnel is expected to reduce the travel distance by 12 km, saving motorists 40-45 minutes and cutting fuel consumption by an estimated 10.5 lakh metric tonnes annually. Vehicles will be able to travel at a top speed of 80 km/h.
Special systems for ventilation, smoke detection, jet fans, and drainage will ensure safety and fresh air inside the tunnel. The project is also expected to reduce carbon dioxide emissions by 36 per cent.
