Clad in shirt and denims and wearing a yellow safety helmet, the young foreman climbs the makeshift stairs — equivalent to a seven-storey building — to reach the top of the underconstruction Metro line at Dhaula Kuan.
The lushgreen Delhi Ridge sprawls before him. The city’s landmarks — Gopal Das Towers, Civic Centre, Antriksh Bhawan — can be seen in the distance. A train speeds by on the Airport Express Line. Further below, traffic moves smoothly on the Ring Road.
The foreman directs all workers to climb down. The Prime Minister’s cavalcade is scheduled to pass through the route in an hour and police have asked the Delhi Metro Rail Corporation (DMRC) to stop all activity until the cavalcade has passed.
The 59-km Brown Line, also known as the Ring Road Metro Line, from Majlis Park to Shiv Vihar will pass over the Airport Express Line (Orange Line) between Delhi Cantt and South Campus stations. It is being touted as an “engineering achievement” by the DMRC.
While the Airport Express Line runs 11.7m above the ground, the height of the Brown Line at this spot will be 23.6m — as high as a seven-storey building. It will also be the highest point of the Delhi Metro so far, surpassing the Karkardooma station, where the tracks run 19m above the ground.
At 12.30 am on Thursday, the foreman and his team will begin installation of the last segment of the viaduct passing over the Airport Express Line.
Since the task involves construction above an already operating line, DMRC officials said they have just 3.5 hours — from half past midnight until 4 am — to ensure the segments are lifted from the ground and attached together to Macalloy bars suspended at that height.
DMRC engineers at the site said “extreme precaution” needs to be taken when the segments are being lifted. “These segments weigh 45 tonnes. The maximum a segment can weigh is 50 tonnes and minimum 30 tonnes. Normally, it takes us just half-an-hour to lift a segment. But at this stretch, it takes us about three hours to complete the process of lifting and joining the segments. We are extremely careful because if the Over Head Electrical (OHE) wires of the Airport Line get damaged due to construction work, it will pose a major issue for commuters. There is also a serious risk of electrocution,” a Metro official said.
DMRC has reportedly installed CCTV cameras at various locations on the viaduct of the Airport Line to monitor construction.
A span of 37m, comprising 13 segments, has been used to construct the viaduct. The launching operation above the Airport Express Line is being done only during the non-operating hours to avoid any disruption to traffic on the Orange Line.