Mumbai: Orange Gate Road Tunnel Project Begins With Geotechnical Survey

The Mumbai Metropolitan Region Development Authority (MMRDA) has commenced the geotechnical investigation work for the proposed underground Orange Gate Road Tunnel Project.

This comprehensive assessment will delve into the physical properties of the soil and rocks along the proposed routes.

According to an Indian Express report, surveys are presently ongoing at about 35 sites, with testing already concluded at seven of them. The report also indicates that survey operations are anticipated to wrap up in the coming days, setting the stage for the commencement of actual tunneling operations after the monsoon season.

The Eastern Freeway, linking Mankhurd to Chembur Junction and Orange Gate on P'Dimello Road, has notably enhanced transportation access to South Mumbai. However, the increased traffic at Orange Gate poses a significant challenge for both the Mumbai Port Trust and the Main Post Office square on P'Dimello Marg.

To mitigate these concerns and establish a seamless road network, the MMRDA is constructing a 9.23 km corridor that will link the Orange Gate at Eastern Freeway and the coastal road at Marine Drive.

The project includes a 6.51 km twin-tube underground tunnel, with each tunnel accommodating 2+2 traffic lanes, 1+1 emergency lanes, and pedestrian walkways.

The project blueprint also includes the construction of a viaduct for vehicle access at the Eastern Freeway Orange Gate, open cuts, and access roads flanking both sides of the corridor.

Safety considerations are paramount, particularly concerning the nearby Mumbai Metro Line-3 project. Therefore, the tunnel's depth will be approximately 40 metres from ground level, ensuring it does not interfere with central rail lines or high-rise building foundations.

In September 2023, the MMRDA approved the appointment of Larson & Toubro (L&T) as the contractor for the construction of the underground tunnel.

The major scope of work for the project comprises of design and construction of twin road tunnels, using Tunnel Boring Machines (TBMs), and connecting these tunnels to the existing elevated Eastern Freeway at Orange Gate near its southern terminal through transition ramps and to the Marine drive at Mumbai. 

The project alignment will run primarily under the Sardar Vallabhbhai Patel Road and is to be completed within 54 months.