CHENNAI: One of the two shafts in the underground Metro Rail stretch between Washermanpet and Korrukkupet was completed on Sunday, which officials claimed was five months ahead of schedule.
Metro Rail officials hope the other shaft too would be completed by next month-end and the entire 9 km stretch connecting Washermanpet and Wimco Nagar would be operational by 2019.
Construction of the 1.82 km-long underground stretch between Washermenpet and Korrukkupet started last July after the Centre approved the extension of Metro Rail in north Chennai at an estimated cost of Rs 3,770 crore. “We optimised the space and machinery to run ahead of the deadline. We used smaller and more efficient machinery, and this helped us reduce the space for maintenance outside the track,” said a senior official from Afcons, the company engaged in tunnelling, adding that soil conditions were favourable.
With the completion of the shaft, the major portion of the work in the underground stretch is over and officials say what is left is laying of the tracks on the shaft and building of the stations. There will be two stations in this underground stretch – Theagaraya College and Korukkupet. The remaining stretch of the line will be an elevated corridor.
The officials said these two stations would be only a fourth when compared to other Metro Rail stations. This was to ease both labour and funds involved in construction and maintenance. The existing underground stations have two levels; the second level accommodating ticket counters, smart card top-up kiosks and information desk, and the platform at an average depth of 18m. The new facilities will not have this concourse level.
Sensors were installed in all the neighbouring buildings to check for cracks and impact of the break through of the tunnel. “These sensors were placed at 30m gaps and showed that buildings did not face much impact from the break through,” an official in charge of safety and quality management said.
Once the underground portion is completed, the project will be taken over by IL&FS Transportation Networks Limited.