38% of tunnelling for Mumbai’s underground Metro completed

MMRC completed a fifth tunnel breakthrough at the Chhatrapati Shivaji International Airport (CSIA) — T2 Metro station

The Mumbai Metro Rail Corporation (MMRC) on Wednesday completed 38% — 20km of the total 52km — of tunnelling for the fully underground Metro-3 (Colaba-Bandra-Seepz) corridor. It completed a fifth tunnel breakthrough at the Chhatrapati Shivaji International Airport (CSIA) — T2 Metro station.

Authorities completed a 5th tunnel breakthrough at the Chhatrapati Shivaji Int’l Airport — T2 Metro station on Wednesday. (Pramod Thakur/HT Photo)

SK Gupta, director (projects), who was present at the site, said, “With this, we have completed 35% of the overall work. These are major milestones for us.”

Gupta said there would be 32 tunnel breakthroughs for the fully underground project. The next tunnel breakthrough is expected at Sahar Road in the coming days.

The tunnel-boring machine — Wainganga 3 — made the breakthrough at 4pm amid loud cheers from nearly 150 engineers, technicians and workers at the site. A press release issued by MMRC stated that the machine started its journey from the Pali ground, completing a drive of 1.31kms i.e it bored about 4.2m daily.

This tunnel was part of package 7 that includes three stations — Marol Naka, MIDC and Seepz.

Of the total 7.07km of tunnelling expected to be completed in this package, 3.56km has been completed.

The 33.5km Colaba-Bandra-Seepz corridor is divided into seven packages. The intent of dividing the corridor in many packages is to complete the sections simultaneously, officials said.

The first phase of the underground corridor is expected to be operational from 2021.

On January 31, a twin tunnel breakthrough was completed between the Nayanagar launching shaft and Dadar metro station. Also, the line will be the second metro in the country to have tunnels under a riverbed, with two tunnels of 1.18km in length to be built 12.5m below the Mithi riverbed.