Tunnelling work for phase II of Chennai Metro to begin in June

The 21-km stretch between Madhavaram and Taramani to be taken up first

Work on phase II of Chennai Metro is set to begin on a massive scale in June, with tunnelling work all the way from Madhavaram to Taramani.

Giant tunnel boring machines (TBMs) will be back in the city. The tunnelling will be carried out on two stretches — a 9-km stretch from Venugopal Nagar in Madhavaram to Kellys and another 12-km stretch from Kellys to Taramani Road Junction.

According to Chennai Metro Rail Limited (CMRL) officials, they have called for tenders and the contractor for the stretches will be finalised in about two months. “After preliminary works, the tunnelling work will commence at various locations in the city,” an official said.

In phase II, 52 km will be funded by Japan International Cooperation Agency (JICA) and the 12-km stretch is a part of it. Therefore, CMRL had to obtain the agency’s approval before calling for tenders.

“We recently got the go-ahead from JICA and hence called for the tenders. Now that the work will begin by the middle of this year, we hope to maintain speed and finish it at the earliest,” another official said.

2 TBMs to be deployed

Two TBMs — one for onward and another for the return — will bore the earth simultaneously between Venugopal Nagar and Kellys and between Kellys and Taramani as well. Usually, the TBMs complete 6-10 metres a day but this may vary, depending on soil conditions. “We will make sure that there are no cracks in buildings or any other damage due to the tunnelling work. We have checked soil samples every 25 metres so that we know how to handle the machines and operate accordingly without causing any damage,” an official said.

In a few weeks, CMRL will call for tenders to build stations along the 21-km stretch. It decided not to hand over the tunnelling and station construction work to the same contractor in phase II. “Even if one contractor’s work is slow, it won’t affect the other. Depending on one firm for the whole construction could delay the entire project,” the official said.

https://www.thehindu.com/news/cities/chennai/tunnelling-work-for-phase-ii-of-chennai-metro-to-begin-in-june/article30498186.ece