Mumbai’s 22-km Versova-Dahisar Link Road project has moved closer to construction, with two massive tunnel boring machines (TBMs) undergoing factory testing in Chennai ahead of their deployment in the western suburbs. The machines will excavate twin underground road tunnels between Mindspace in Malad and Charkop Creek as part of the Brihanmumbai Municipal Corporation’s (BMC) Coastal Road (North) project.
With cutterhead diameters of 15.6 metres, the machines are among the largest being deployed for a road tunnel project in India. Manufactured in Germany, they are being assembled at the Herrenknecht India facility in Chennai. BMC officials recently inspected one machine’s systems during factory acceptance testing.
“We inspected all the machine parameters, including the rotation of the cutterhead, functioning of the shield, grouting system, pressure levels and thrust jacks that propel the TBM forward, as well as the segment-lifting mechanism,” a civic official told TOI.
The machines, each approximately 87 metres long when assembled, will be dismantled and transported to Mumbai in components using around 95 to 100 trailers. Limited storage space along the alignment and challenging conditions near creek and mangrove areas have added to the logistical difficulties.
“There is little space to store the machines’ large components along the alignment. This differs from the south Coastal Road project, where reclaimed land provided some room to handle and store construction material,” a BMC official told TOI.
Preparatory work on the launching shaft at Charkop began in August. Measuring approximately 31 metres by 120 metres, the facility will accommodate the machines before tunnelling begins, which is scheduled for May 2027.
The twin tunnels will extend 3.9 km, with approximately 3 km excavated using TBMs and the remaining 900 metres constructed through the cut-and-cover method. Each tunnel will have a finished internal diameter of 14.2 metres and pass nearly 40 metres underground through hard basalt rock.
The corridor is expected to ease pressure on the Western Express Highway and improve suburban connectivity. However, environmental concerns remain, with around 45,000 of the estimated 60,000 mangroves in the project’s influence zone expected to be impacted. Compensatory plantation is planned in Bhayander and Chandrapur.
Source: Economic Times
