British-era rail bridge over Mithi River replaced with steel girders

MUMBAI: This week, the local trains will slow down each time they enter the Bandra-Mahim stretch. This is owing to the 20-30 kmph speed restriction enforced by the Western Railway (WR) over the Mithi River, which be slowly eased to 45 kmph by the end of the week. During the weekend, the British-era cast iron piles of the rail bridge, over which the tracks are placed, were replaced with steel girders.

Over two intervening nights between Friday and Sunday, the WR authorities carried out the second phase of replacing the old cast iron screw piles, which is the last on Indian Railways, with steel girders. WR used a block of 9.5 hours each night, and the two mega blocks led to the cancellation of 334 services.

According to WR engineers, as part of phase-2, they dismantled the abutments on cast iron piles and rebuilt it. They also launched steel girders, electrical, and signal and transmission (S&T) gears.

“The work was executed by deploying 700MT crane with one standby crane, 10 dumpers, a Poclain, two JCBs, a tamping machine, tower wagons, and about 150 manpower. This will benefit the safe running of trains, which used to be an issue as the cast iron pile foundations were in poor condition,” said a WR official. The cast iron pile foundations, due to its age, posed a threat of sudden collapse.

The official said some challenges were faced such as the finalization of a suitable plan to reduce the impact on suburban rail traffic and the construction of a ‘coffer dam’ on the east and west sides of existing piers in Mithi River for having a two-way water flow to prevent water ingress while work was going on. As there no direct way to approach the bridge site, all machinery and materials were moved by blocking 3 stabling lines, which is used to park trains at night.