October 7, 2025: Work on the long-awaited Thane–Borivli twin-tube tunnel is finally set to accelerate, with construction scheduled to begin this December beneath the Sanjay Gandhi National Park (SGNP). Estimated to cost Rs 16,600 crore, the mega infrastructure project will connect the Western Express Highway in Borivli to the Eastern Express Highway via Ghodbunder Road, cutting travel time between Mumbai’s eastern and western suburbs by nearly three-quarters.
A senior Mumbai Metropolitan Region Development Authority (MMRDA) official confirmed that preliminary work has commenced. “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,” the official said. The project carries a three-year deadline and will adhere to stringent safety and environmental norms.
The twin-tube structure will span 11.8 kilometres, comprising 10.25 kilometres of tunnel and 1.55 kilometres of approach road. Each tunnel will include two lanes and an emergency lane, with cross-passages at every 300 metres. The outer diameter of each tube will measure 13.05 metres.
Construction will be executed in three packages: a 5.75 km tunnel on the Borivli side, a 6.05 km tunnel on the Thane side, and a third covering electrical and mechanical systems such as ventilation, fire safety, and drainage.
The tunnel is designed to reduce the travel distance by 12 km, saving motorists up to 45 minutes and reducing annual fuel consumption by an estimated 10.5 lakh metric tonnes. Vehicles will be able to travel at speeds of up to 80 km/h.
Equipped with advanced ventilation, smoke detection, jet fans, and drainage systems, the tunnel will enhance commuter safety and improve air quality. Once operational, it is expected to cut carbon dioxide emissions by 36% making it one of Mumbai’s cleanest and most efficient transport corridors.
Source: Mid-day
