Namma Metro Pink Line Set For 2025 Launch As TBM Tunga Breaks Records With 308 Metres Of Tunneling in July

Namma Metro's Tunnel Boring Machine (TBM) Tunga has set a new tunneling record. In July, Tunga bored through 308 metres, surpassing the previous record of 273 metres held by TBM Urja from May 2022, as reported by Bangalore Metro Rail Corporation Limited (BMRCL).

BMRCL stated, "In July 2024, we achieved our highest tunneling rate to date. TBM Tunga completed 308 metres of tunneling between K.G. Halli and the Nagawara retrieval shaft, exceeding the previous record of 273 metres achieved by TBM Urja between Cantonment and Pottery Town in May 2022."

BMRCL has deployed nine TBMs for Namma Metro construction across Bengaluru. Seven of these machines-Urja, Varada, Avni, Lavi, Vindhya, Vamika, and Rudra-have successfully finished their tasks.

The eighth TBM, Tunga, began its final drive from K.G. Halli to Nagawara on February 2 for the Pink Line, covering 935 metres. The ninth TBM, Bhadra, is currently working on its final assignment, a 939-metre northbound tunnel from K.G. Halli to Nagawara.

Maximum Tunnelling done in a month in BMRCL so far . In July 2024, 308m of tunnelling is done by Tunga TBM between KG Halli towards Nagawara retrieval shaft by M/s ITD. Earlier best was 273m by Urja TBM between Cantonment and Pottery town in May2022 by M/s L&T. FKI

— ನಮ್ಮ ಮೆಟ್ರೋ (@OfficialBMRCL) August 1, 2024

Tunneling with Tunga was briefly halted in July due to a sinkhole that appeared on the K.G. Halli road surface. Officials estimated the sinkhole, approximately 2.5 to 3 metres wide and 3 metres deep, was likely caused by an air pocket. After repairs, Tunga resumed its work.

Officials anticipate that Tunga will reach Nagawara, the Pink Line's terminal station, by October 30. Having started its final drive on February 3, Tunga has already completed 469 metres of the total 938-metre goal.

The Pink Line is expected to open in 2025. However, progress has faced delays due to factors such as tender cancellations due to high bids, changes in alignment, land acquisition challenges, and other issues. Despite these setbacks, officials remain hopeful that the full stretch will be completed and operational by 2025.