Wedoany.com Report-Dec.16, Chennai Metro Rail Limited (CMRL) initiated operations of a tunnel boring machine (TBM) on December 12, 2025, for the Panagal Park to Boat Club section of Corridor 4, advancing underground construction within the city's Phase 2 metro expansion. This phase encompasses three corridors spanning 118.9 kilometers with 128 stations.

Corridor 4 extends 26.1 kilometers from Light House at Marina Beach to Poonamallee Bypass, incorporating a significant underground segment between Light House and Kodambakkam Flyover. This segment is divided into two packages, UG-01 and UG-02, utilizing four TBMs with a 6.67-meter excavation diameter to construct approximately 16 kilometers of twin tunnels.

The recently launched TBM, part of package UG-02, targets the stretch between Panagal Park and Boat Club. Named "Peacock," this machine previously completed a 2-kilometer tunneling drive from Panagal Park to a retrieval shaft near Meenakshi College on Arcot Road, achieving the first breakthrough for Corridor 4's underground portion on July 23, 2025. That effort involved tunneling beneath active Indian Railways tracks.

Following completion, Peacock was disassembled at Kodambakkam, transported back to Panagal Park, and reassembled for a new 1.89-kilometer drive toward Boat Club Station. It is the first TBM deployed for one of the twin tunnels in this section.

The current tunneling route passes under operational Phase 1 metro tunnels near Nandanam Metro Station, with depths reaching up to 30.2 meters below ground. Starting on the down line of Corridor 4, Peacock will progress from Panagal Park through Nandanam to a retrieval shaft at Boat Club Station.

CMRL anticipates completing this tunneling segment by November 2026. The project reflects ongoing efforts to expand urban transit infrastructure, enhancing connectivity across Chennai through efficient and modern metro systems.

The use of TBMs allows precise construction in dense urban environments, minimizing surface disruption while ensuring structural integrity. Corridor 4's underground design accommodates complex alignments, navigating existing infrastructure like railway lines and metro tunnels with advanced engineering techniques.

This phase of work underscores CMRL's commitment to delivering reliable public transportation, supporting increased mobility and urban development in one of India's major metropolitan areas.