Dogus-Soma Restarts Mumbai Metro’s TBM 1239 towards Mahalaxmi

This past weekend, workers from Doğuş-Soma JV recommissioned their second tunnel boring machine (TBM) 1239 from Science Museum Station’s southern-end towards Mahalaxmi Station for Mumbai Metro’s 33.5 km underground Line-3 (Aqua Line).

This Ø6.65m Robbins slurry machine, nicknamed Tansa 2, had achieved a breakthrough at Worli Station in March 2020 from Science Museum Station after a 2057 meter journey for building the down-line tunnel to record the second out of 6 planned for package UGC-03 (Worli – Mumbai Central). Following that, its cutterhead and shields – weighing 480 MT – were retrieved as one complete unit in August, transported through the city’s streets, and lowered back into Science Museum in September.

This weekend, the TBM began its second assignment to build the 1118m up-line tunnel towards Mahalaxmi Station from where it will be dragged to the station box’s southern-end and recommissioned onwards to Mumbai Central Station for its final 837m assignment.

Its sister machine TBM 1238 (Tansa-1), which was recommissioned in September for the parallel down-line tunnel, has since built 74 rings (approx. 103 meters) towards Mahalaxmi Station.

With this development – here’s a table displaying UGC-03’s tunneling plan and status of each tunnel (best viewed on a desktop device). Note that TBM 1238 and 1239 had switched positions (up-line to down-line and down-line to up-line) for their onward journeys.

TBM	Line	From	To	Distance	Status
1	Up	Science Museum	Worli	2072m	Completed Jan 2020
1	Down	Science Museum	Mahalaxmi	1136m	In Progress
1	Down	Mahalaxmi	Mumbai Central	830m	Pending Start
2	Down	Science Museum	Worli	2057m	Completed March 2020
2	Up	Science Museum	Mahalaxmi	1118m	In Progress (This Post!)
2	Up	Mahalaxmi	Mumbai Central	837m	Pending Start

In other tunneling news, L&T-STEC JV’s Robbins TBM Surya-1 on Package UGC-01 will today likely make its third of fourth planned breakthroughs at Hutatma Chowk Station for the 649m up-line tunnel from Churchgate. Stay tuned for a post with pictures!

For more updates, check out the Mumbai section of The Metro Rail Guy!

– TMRG