Chennai: A tunnel-boring machine (TBM) named Nilgiri worked at a speed of 1.5 metres a day for the past 10 months at around 15 metres depth to complete a 1.4-km-long tunnel from Madhavaram Milk Colony to Madhavaram High Road on Monday.
It was the second machine to complete tunnelling in the 116.1km phase-2 project at Madhavaram. In 2024, 23 TBMs will be working in tandem across the city.
On Monday evening, the 700-tonne Nilgiri broke through a concrete wall 15 metres under the busy Madhavaram High Road to loud cheers from workers. The stretch is part of the 42km corridor-3 with 46 stations from Madhavaram Milk Colony to Siruseri Sipcot.
