Delhi Metro on Wednesday completed tunnelling work between Chhattarpur and Chhattarpur Mandir Station on the golden line on the Tughlakabad - Aerocity corridor in the presence of Lieutenant Governor Vinai Kumar Saxena and Delhi Transport Minister Kailash Gahlot.

In a statement by the corporation, it stated, “The Delhi Metro Rail Corporation (DMRC) achieved a major construction milestone in Phase 4 with the completion of tunnelling work between Chhattarpur and Chhattarpur Mandir Station on the Tughlakabad-Aerocity corridor.”

It added that a Tunnel Boring Machine (TBM) broke through this morning at Chhattarpur Mandir Station after boring an 865 meter long tunnel. “This tunnel breakthrough was achieved using a mammoth 97-metre-long TBM. Two parallel circular tunnels for up and down movement are being constructed on this stretch as part of the Aerocity - Tughlakabad corridor. The work on the other tunnel parallel tunnel on this section will be completed by September this year,” it said, adding that the new tunnel has been constructed approximately at an average depth of 15 metres and about 618 rings have been installed in the tunnel.

Chief Secretary Naresh Kumar, Principal Secretary to Saxena Ashish Kundra and Officer on Special Duty (UT) of Ministry of Housing and Urban Affairs Jaideep also graced the occasion in the presence of Managing Director of DMRC Dr Vikas Kumar and other senior officials.

“It has an inner diameter of 5.8 metres. The tunnelling work involved innumerable challenges like shifting of 66 KV electrical HT line. In addition, crossing of TBM was carried out below the existing Yellow Line viaduct without disturbing the Metro train operations on Yellow line,” the statement said.

The tunnel has been built with the proven technology of EPBM (Earth pressure balancing method).