Tata Projects Limited has launched the first Tunnel Boring Machine (TBM) for Corridor 5 of its Phase II expansion project. Named TBM Kurinji, the machine was deployed at the Kolathur Ramp on February 19, 2025, marking a significant milestone in Chennai’s metro development.

Following the successful implementation of Phase I and its extension, CMRL has embarked on an ambitious Phase II expansion, covering 118.9 km across three new corridors, backed by international funding from JICA, ADB, AIIB, and NDB. Corridor 5, spanning 47 km, originates at Madhavaram Milk Colony and passes through key locations such as Koyambedu, Porur, and Alandur, ultimately linking to Shollinganallur. The corridor features five underground stations and 39 elevated stations.

As part of the tunneling strategy, four TBMs, named after Tamil landscapes—Kurinji, Mullai, Marutham, and Neithal—have been designated for Corridor 5. TBM Kurinji will excavate a 246-meter tunnel from Kolathur Ramp towards Kolathur Station (upline), with completion expected by June 2025. It will then be retrieved and relaunched from the south shaft to tunnel towards Srinivasa Nagar (1.06 km). The second TBM, Mullai, is scheduled to arrive by March 2025, commencing tunneling from Villivakkam Railway Station to Villivakkam Bus Terminus, covering 603 meters. The remaining TBMs will be deployed progressively as site conditions permit.

The 7.8 km underground section of Corridor 5 consists of twin tunnels (3.9 km each) extending from Kolathur Ramp to Nathamuni Ramp. Tata Projects Limited, entrusted with executing this critical infrastructure project, is responsible for mobilizing all four TBMs.

With the launch of TBM Kurinji, Chennai’s metro expansion advances further, enhancing urban connectivity and reducing traffic congestion, paving the way for a more efficient and sustainable transit network.