Bangalore Metro – September 1 Tunneling Update

With the Krishna TBM’s breakthrough at Chickpet station behind us (See: [Pics] TBM Krishna Finally Makes a Breakthrough at Chickpet), we’re now down to the last 4 tunneling drives that have to be made to complete Phase 1 of the Bangalore Metro project. All 4 tunneling drives will occur on the 24.20 km north-south Green line that is being constructed from Nagasandra to Puttenahalli. The east-west Purple line’s tunnels are complete and trial runs are expected to begin in the next couple of weeks.

The contractor of the underground section from the North Ramp (just south of the Sampige Road station) to the south ramp (north of National College station), a joint venture of Coastal-TTS, has deployed 4 TBMs which are in various stages of tunneling. Incidentally, the tunneling schedule has been configured in such a way that 3 breakthroughs will take place at the Majestic interchange station in the heart of the city and 1 breakthrough will take place at the North Ramp.

Here’s a map to just show the general launching point & direction of the tunneling drives. It does not represent the actual distance covered by the TBMs.

• Green Arrow – The Godavari TBM was originally launched from the north ramp towards Majestic station in August 2014 but after covering a distance of 352 meters, it ran into hard rock right before the railway line (where the arrow above unintentionally points). As such, the cutterheard was severely damaged and that rendered the machine immobile for months as a new cutterhead worth Rs 5 crore had to be ordered from a company called Palmeiri based in Italy. That cutterhead was fixed in late July (See: New Cutterhead Fixed on TBM Godavari) and tunneling is expected to resume in the next couple of days.
Distance left – 615 meters

• Maroon Arrow – The Margarita TBM started tunneling from the Majestic station towards the north ramp in October 2014. It is an advanced stage of tunneling and is expected to make a breakthrough in about one and a half months (mid October).
Distance left – 200 meters

• Blue Arrow – The Kaveri TBM was launched from the Chickpet station in February 2015 and has completed roughly 350 meters. This is expected to make a breakthrough at the Majestic station in January 2016.
Distance left – 400 meters

• Orange Arrow – The Krishna TBM just made a breakthrough at Chickpet station from the KR (City) Market station (See: [Pics] TBM Krishna Finally Makes a Breakthrough at Chickpet) after a slow and tiring journey of 22 months. The TBM will now take some much needed rest and go through repairs for roughly 45 days during which parts of it will be dismantled for transportation to the other end of the station. After that it will continue its northward journey to the Majestic station for one final drive. Tunneling on that section is expected to start in mid October and hopefully end by February/March 2016.
Distance Left – 747 meters

The BMRC’s official newsletter for this month will be published soon and that will provide the “official” distance covered by each TBM. Whenever that is published, I will make sure to make a follow up post.

For more updates on the Bangalore Metro, check out the Bangalore section of the TMRG!

– TMRG