Surya-1 Makes Final Breakthrough for Mumbai Metro Line-3’s UGC-01

Besides the start of trial runs on Line-2A and Line-7, another signficant milestone was recorded today!

Moments ago, Tunnel Boring Machine Surya-1 operated by Larsen & Toubro – Shanghai Tunnel Engineering Company JV arrived at Chhatrapati Shivaji Maharaj Terminus on Mumbai Metro’s 33.5 km Line-3 (Aqua Line).

This was L&T-STEC JV’s 8th and final breakthough for the 4.25 km Package UGC-01’s tunnels between Cuffe Parade and CSMT. Overall, this was Line-3’s 38th of 42 planned TBM breakthroughs.

This Robbins Crossover XRE TBM (XRE2114-408) had recorded a breakthrough in November at Hutatma Chowk Station’s southern-end from Churchgate, and was then dragged to its northern-end through the 233 meter long station box using hydraulic jacks.

It was then re-commissioned for its 4th assignment on December 31 on its 4th assignment towards CSMT (or CST) Station to build its final 551 meter long tunnel for Line-3’s up-line.

With this development, here’s a recap of Package UGC-01 between Cuffe Parade and CST / CSMT stations where all tunneling works are now over.

This table is best viewed on a desktop device –

TBM	Line	From	To	Distance	Status
1	Up	Cuffe Parade	Vidhan Bhavan	1128m	Completed
1	Up	Vidhan Bhavan	Churchgate	498m	Completed
1	Up	Churchgate	Hutatma Chowk	649m	Completed
1	Up	Hutatma Chowk	CST	551m	Completed (this post!)
2	Down	Cuffe Parade	Vidhan Bhavan	1254m	Completed
2	Down	Vidhan Bhavan	Churchgate	481m	Completed
2	Down	Churchgate	Hutatma Chowk	653m	Completed
2	Down	Hutatma Chowk	CST	556m	Completed

Tunneling works on 6 out of 7 underground civil packages have been wrapped up –

• UGC-01: Cuffe Parade – CST (4.25 km) – Final breakthrough recorded by TBM Surya-1 today!
• UGC-02: CST – Mumbai Central (4.049 km) – Final breakthrough recorded by TBM T59 (Vaitarna-2) in April 2020
• UGC-04: Worli – Dharavi (6.08 km) – Final breakthrough recorded by TBM S1073 (Krishna-1) in December 2020
• UGC-05: Dharavi – MVS near CSIA T1 (4.94 km) – Final breakthrough recorded by TBM S64 (Godavari-4) in August 2020
• UGC-06: Santa Cruz MVS – CSIA T2 (4.45km) – Final breakthrough recorded by T62 (Tapi 2) in February 2021
• UGC-07: CSIA T2 – Sariput Ramp (4.157 km) – Final breakthrough recorded by TBM D213 (Wainganga-2) in December 2019.

Roughly 95% of Mumbai Metro Line-3’s tunneling has been completed and now just 2 TBMs are actively tunneling from an all time high of 17.

A total of 38 breakthroughs have been recorded so far with the following 4 pending on UGC-03. Both Robbins machines have been struggling on this section with frequent interventions and replacement of parts required.

I will add both machines’ progress when available.

Package	Section	Distance, Status
UGC-03	Science Museum – Mahalaxmi (up-line)	1118m, In Progress
UGC-03	Mahalaxmi – Mumbai Central (up-line)	837m, Not Started
UGC-03	Science Museum – Mahalaxmi (down-line)	1136m, In Progress
UGC-03	Mahalaxmi – Mumbai Central (down-line)	830m, Not Started

For more updates, check out my Home Page!

– TMRG