Tunnel created below Najafgarh Nullah
First Delhi Metro construction below a water body
The water now flows above the Metro tunnel
NEW DELHI: After constructing rail tracks for the Metro both under and above ground, the Delhi Metro Rail Corporation (DMRC) has successfully created a tunnel below the bed of the Najafgarh Nullah (drain) on the Vishwavidyala-Jahangirpuri corridor of Phase-II.
This is the first time a part of the Delhi Metro network is being constructed below a water body, DMRC official claimed.
“The final tunnel breakthrough took place today when the last portion of soil that separated tunnels being dug from both sides was finally broken through. The top of the tunnel is about 0.5 metres and its base 6.7 metres below the bed of the drain. The total length of the tunnel on the Vishwavidyalaya-Jahangirpuri section is 1 km of which 40 metres is directly below the drain,” said DMRC Chief Public Relations Officer Anuj Dayal.
Work began in May
The construction work on the tunnel started in May this year.
“The construction of the Delhi Metro below the Najafgarh Nullah, which is near the Vishwavidyalaya station, presented a unique challenge as the tunnel had to be constructed below the bed of the drain and a bridge above it, thus making it a three-tier crossing,” Mr. Dayal said.
Explaining how the work was carried out, he said two temporary steel bridges were built above the drain to avoid a traffic blockade.
Care was also taken to ensure that the flow of the drain was not stopped at any time, as that would have resulted in inconvenience to the public.
Original flow restored
The original flow of the drain has since been restored and the water now flows above the Metro tunnel. The original road above the drain will be restored within three months.
The 6.36-km Vishwavidyalaya-Jahangirpuri corridor is scheduled to be opened in October 2009 and construction is progressing according to schedule.