December 3, 2025: Around 14% of construction on the underground tunnel connecting Orange Gate on the Eastern Freeway to Marine Drive has been completed, the Mumbai Metropolitan Region Development Authority (MMRDA) announced on Tuesday. The Rs 8,056-crore project, designed to significantly improve east–west connectivity in the city, is slated for completion in 54 months.
Once operational, the tunnel will shorten travel time by 15–20 minutes, reduce fuel consumption, and help lower air and noise pollution. It is set to become the first urban tunnel in India to pass underneath a densely populated area, cutting below the Central and Western Railway corridors as well as Mumbai Metro Line 3 at a maximum depth of nearly 50 metres.
The total tunnel stretch measures 9.96 km, including about 7 km of underground roadway. Each tunnel will include two 3.20-metre traffic lanes and a 2.50-metre emergency lane, with a planned speed limit of 80 km/h. For safety, cross passages will link the two tunnels every 300 metres. The depth along the alignment ranges from 12–52 metres, and the system will incorporate mechanised ventilation, fire-resistant installations, intelligent lighting and an Intelligent Transport System (ITS) to ensure smooth operations.
A key advantage of the underground alignment is minimal land acquisition, helping preserve the urban landscape and limit disruption. The tunnel will integrate seamlessly with major projects such as the Coastal Road and Atal Setu, strengthening Mumbai’s overall mobility network.
Construction will rely on a slurry-shield tunnel boring machine (TBM), chosen for its suitability to Mumbai’s coastal geology and high water ingress conditions. MMRDA stated that this advanced technology will ensure precision, stability, and safety throughout excavation, marking a major milestone in the city’s ongoing infrastructure transformation.
Source: The Free Press Journal
