Life...working on a Metro when Mumbai winds down for the night

As Mumbai winds down for the night, traffic diversions are put it in place at midnight on the Western Urban Road. Halogen lamps are switched on, and the stage is set for a team of about 40 men, comprising launching engineers, supervisors and riggers, to execute detailed plans and give actual shape to the 16.5-km Mumbai Metro 7 project from Dahisar (East) to Andheri (East). Every night, this team ensures that work on the Metro route progresses by 25 metres.

While the ground work of piling and laying pillars continues through the day, it's during the graveyard shift that construction work intensifies on this key infrastructure project, meant to provide a more comfortable commute to Mumbaikars, and ease the burden on the suburban railway network.

At 11:50 pm at Pathanwadi Naka on the Western Urban Road in Malad on a weekday, traffic flows smoothly on the highway. At the construction site, day shift workers pack up and call it a day after hours of gruelling piling work, even as the night shift team waits for police to arrive and close the road to traffic.

At around 12:30 am, the traffic cops divert north-bound traffic on the highway through 'counter-laning', creating a dedicated lane for north-bound traffic on the south-bound arm of the highway. The section of the highway along the metro construction site at Pathanwadi Naka is closed to traffic.

An otherwise low drone at the construction site is gradually replaced by the loud clamour of the motors of heavy machines and three massive cranes swing into action. A lifting crane, to carry workers up to the necessary elevation, and two other cranes to lift the U-girder on which the Metro tracks will be eventually laid, start moving into position for 'launching' operations. The team gathers at a spot where a launching engineer briefs them on the work to be done.

After briefing, the team is divided into four groups. The lifting crane carries two teams up to the pillars to inspect them and lay a pedestal, bearings, plates and industrial glue, over which the U-girder will be placed. Two other teams clear the way for the two cranes to take their position alongside two successive pillars. As the cranes take their position, the team begins counterweighing them.

According to the launching engineer, every night, two U-girders are supposed to be laid in parallel atop two successive pillars or piers. To execute this task, the two cranes are placed beside the two pillars at a distance of 120 feet from each other. The booms and lifters of these two cranes are then connected to the two ends of the girder, which is then lifted to the height of the piers and placed on them.

"After coming around 12 am every night, I move the crane into position, keep the counter weights on the crane and then lift the girder to place it on the piers after the launching engineer gives the signal to place it. There are two safety managers who give permission after checking the status of the crane," says a crane operator.

Amit Kapoor, a launching engineer at the site says, "Launching the girder is a major task for us. It is brought to the site at around 3 am every night and positioned between the two piers. The cranes capable of lifting 400 tonnes each are then connected to the girder. Two teams are sent up to the two piers, and they signal the crane operators to ensure the girder is placed."

"As soon as the traffic police closes this section of the highway, we have to prepare the machines, keep the counterweight on the cranes and have to clear the way for the trailers to enter. We can't go wrong as an error could lead to a major mishap as well as a delay in launching the girder," Kapoor says.

He adds, "We usually finish our work by 5 am, but sometimes we get delayed as cannot take a risk with the heavy machines."

The work of piling is done during the morning shift. Piling machines dig up to a depth of 50 metres from the road surface to set the base or 'footer' for the piers. A steel structure is then put in place, and concrete is poured into it to create piers. T-shaped pier caps are installed, on which the ends of the U-girder will be placed later.