Sun Apr 20 14:20:13 UTC 2025: ## Chennai Metro’s Tunnel Boring Machines Hit Snag Due to Construction Delays
**Chennai, April 20, 2025** – Six tunnel boring machines (TBMs) used in the construction of Chennai’s Metro Rail Phase II project are currently idle, awaiting the completion of station construction. The delay, according to CMRL officials, is primarily attributed to the cancellation of station construction tenders four years ago due to unreasonably high bids from contractors.
The TBMs, deployed along corridor 3 (Madhavaram to SIPCOT), are stalled at various locations including Moolakadai, Perambur, and Mandaveli. They are unable to proceed until the diaphragm walls and station boxes are completed. While the TBMs themselves began work on time, the protracted delays in station construction have brought their progress to a standstill.
CMRL officials acknowledge the numerous challenges faced, including utility relocation, borewell shifting, and obtaining permissions for traffic diversions. However, they assure that measures are underway to expedite station construction. They expect all TBMs to break through to their respective stations and resume work by the end of the year.
First Piper 