Chennai Metro Completes Critical Corridor 4 Tunnels
Chennai’s urban transit infrastructure reached a pivotal milestone as the city’s metro authority completed the twin underground tunnels along a key section of Corridor-4 in its Phase-II expansion. The project, running between the Light House and Thirumayilai stations, is expected to significantly enhance mobility across Mylapore, Luz, and surrounding central districts, alleviating congestion in one of the city’s densest urban corridors.
The underground stretch, spanning just under two kilometres, was executed using two tunnel boring machines (TBMs) under a challenging urban environment. Engineers had to navigate rocky strata, minimal soil cover in some sections, deep overburden due to stacked tunnel configurations, and unforeseen pockets of gas. The alignment passes beneath sensitive areas including the Lighthouse precinct, cultural and institutional zones, diplomatic enclaves, and the Buckingham Canal, requiring careful planning to minimise disruption. A senior project official highlighted that the completion of both the upline and downline tunnels removes a long-standing bottleneck in Corridor-4, allowing the city’s metro network to maintain its scheduled timelines for broader Phase-II connectivity. The completion also demonstrates the growing technical capability of urban tunnelling projects in Chennai, balancing efficiency with safety in dense urban settings.
Urban planners note that the enhanced connectivity will support more sustainable commuting patterns, potentially reducing reliance on private vehicles along the corridor’s busy arterial roads. Experts suggest that such metro extensions are critical not only for alleviating traffic but also for promoting compact, transit-oriented urban growth in Chennai, aligning with the city’s wider zero-carbon and climate-resilient development goals. The corridor’s operational readiness is expected to benefit daily commuters, students, and professionals in central Chennai, with improved access to cultural, commercial, and institutional hubs. In addition to daily mobility gains, the metro infrastructure has shown its broader civic relevance: a dedicated train was recently used to transport donated organs from Chennai Airport to a central hospital within minutes, demonstrating how robust metro operations can support critical city services beyond transport.
Analysts emphasise that timely completion of such high-stakes projects under challenging urban conditions is vital for maintaining investor confidence in the city’s real estate and infrastructure sectors. They also point to the potential for integrating green and energy-efficient technologies in upcoming phases to ensure long-term sustainability. With Corridor-4’s underground tunnels now in place, Chennai is poised to advance its Phase-II metro network while providing safer, faster, and more sustainable urban mobility. Authorities are expected to focus next on finishing station construction, system integration, and testing before public operations begin, paving the way for a more connected, equitable city.
