BENGALURU: The final two Tunnel Boring Machines (TBMs) working on Bengaluru Metro’s underground stretch of the Pink Line, from Kalena Agrahara to Nagawara, have encountered rocky terrain, significantly slowing progress. This challenge makes it unlikely to meet the original tunnelling deadline of August-September 2024, pushing the completion to year-end and jeopardizing the March 2025 opening date set by Bangalore Metro Rail Corporation Limited (BMRCL).
Seven of the nine TBMs have finished their tasks, but the last stretch between KG Halli and Nagawara South remains. TBMs Tunga and Bhadra, still drilling, are encountering unexpected rock, slowing their pace to half the usual speed. ITD Cementation India is handling this phase of the project.
A Metro source reported that 19.66km of the 20.99km tunnelling is complete, but the remaining 940 meters are rocky, contrary to geological reports indicating soil. Currently, TBMs cover only 3km per day through rock, compared to 5km through soil.
Completion of this segment is critical, as the Pink Line includes 18 stations, 12 of which are underground. Despite tunnelling delays, additional work at stations and other areas also contribute to the overall timeline.