Achieving breakthrough:TBM Peacock bores through the stretch between Panagal Park and Kodambakkam under Phase -II of the Metro Rail project, on Wednesday.
| Photo Credit: B. JOTHI RAMALINGAM
After 14 months underground, Chennai Metro Rail’s tunnel boring machine ‘Peacock’ made a breakthrough at Kodambakkam on Wednesday, successfully creating a two-km tunnel between Panagal Park and Kodambakkam as part of the upcoming phase II project.
In a couple of years, when the track is laid and stations get ready, you will be able to hop onto this underground line and travel from Kodambakkam to T. Nagar. This section is part of corridor 4 of the phase II project which traverses from Poonamallee to Light House via T. Nagar.
Work began last year
In May 2024, TBM Peacock began boring the earth from Panagal Park. In the last 14 months, the machine created a tunnel under Usman Road flyover and Kodambakkam flyover and the Kodambakkam Suburban Railway Station and snaked its way till Kodambakkam, near Meenakshi College for Women, covering a distance of two km and made a breakthrough on Wednesday afternoon.
The corridor 4 which starts as an elevated section takes a plunge at this point in Kodambakkam, opposite to Meenakshi College for Women, and turns into an underground section till Light House. T. Archunan, director (projects), Chennai Metro Rail Limited (CMRL) said no other tunnel in the city is as long as this stretch (between two stations)and the breakthrough was achieved without unsettling any of the establishments close by. “The diaphragm wall at Kodambakkam was built just three metres away from the Kodambakkam Suburban Railway Line. This was no easy feat. When the TBM bored under the Kodambakkam Suburban Railway Line, the trains passing through the track had speed restrictions of 15 -25 kmph for 15 days. Apart from tunnelling under flyovers and the railway track, the TBM bored under nearly 190 buildings, and a sizable number of them were pretty old, dilapidated ones too,” he said. Dibyendu Choudhuri, former project director for this stretch with ITD Cementation India Limited, said they dealt with mixed soil conditions between Panagal Park – Kodambakkam stretch, which was quite challenging.
“In T. Nagar it was a combination of clayey and sandy soil. Beyond that, it became rock. In some parts in Kodambakkam, while the upper layer was clayey, the lower part was rock which made it a bit difficult to tunnel through. We also had to change the cutter discs on 18 occasions,” he recalled.
Published – July 24, 2025 01:05 am IST
