CHENNAI: The Tunnel Boring Machine (TBM) named Nilgiri (S-96) in corridor 3 of phase 2 metro rail construction had a breakthrough at Madhavaram High Road on Monday.

The Nilgiri drive started in October last year after its inauguration by Chief Minister MK Stalin from Madhavaram Milk Colony Station to Madhavaram High Road.

So far, the tunnel has covered a length of 1.4 km and witnessed a breakthrough at the high road.

The tunnel construction for the first 9 km underground section of corridor 3 from Madhavaram Milk Colony to Kellys is being executed through M/s.Tata Projects limited and seven TBMs have been mobilised for the works.

According to the Chennai Metro Rail Limited (CMRL), tunneling by TBM Servarayan (S-99), which started in May from Madhavaram Milk Colony station to Venugopal Nagar Shaft in the down line, is expected to break through August as well.

Similarly, in June, the tunnel construction for the underground section in corridor 3, from Madhavaram Milk Colony to Kellys, the TBM Anaimalai (S-98) witnessed a breakthrough at Venugopal Nagar shaft.

Anaimalai TBM was transported to the Madhavaram Milk Colony site and lowered into the north side launching shaft in the upline. Subsequently, the drive began in February from Madhavaram milk colony to Venugopal Nagar shaft, covering a bored tunnel length of 415m in four months and achieving a breakthrough in June.

Speaking to media persons, T. Archunan, Director (Project), CMRL said, "There are multiple TBM breakthroughs awaiting in coming months. And, the work for underground construction is pacing at a good speed in corridor 3."

"To make the environment conducive for workers underground, we have made necessary arrangements from supply of oxygen to first aid in case of untoward incidents, " added the director.