Kolkata Metro to join international standard after aluminium third rail retrofitment concludes in 2025

Kolkata Metro Railway is re-commits to conclude the replacement of the existing steel third rail with aluminium resorts on the down line of the Blue Line corridor, spreading between Belgachia and Tollygunge (Mahanayak Uttam Kumar), by August 2025, a spokesperson announced on Sunday, January 5.

According to the Press Information Bureau, in Kolkata Metro Railway, the power to the metro rake is supplied to rolling stock at 750V DC through steel third rail. The Third Rail Current Collector (TRCC) made of steel fitted on metro rake collects the current from third rail. Kolkata Metro Railway has been using steel third rail for the last 40 years. Kolkata Metro Railway decided in August 2023 to use composite aluminium third rail in all the upcoming corridors being undertaken for construction along with retrofitment in existing corridors with steel third rail. With this Metro Railway, Kolkata would become a member of an elite club of London, Moscow, Berlin, Munich, and Istanbul Metro which have also shifted from steel third rail to aluminium ones.

A total of 35 kilometres of mainline steel third rail is being upgraded in phasal schedules, which will then result in huge savings in traction energy costs, like a straight saving of  INR 210 crores (USD 25.3 million) capital investment for 35 kilometres of metro railway corridor.

The third rail replacement concluded between the down line of 4-km distance from Shyambazar to Central stations. On September 7, 2024 the first phase of the alteration began with overnight replacement of steel third rail with aluminium alternatives on the North-South corridors. Till December 2024, around 3.5 kilometres of the third rail were replaced, with an additional 4 kilometres now on the pipeline for monthly replacement schedules to meet the deadline. In the beginning, the upgrade was performed only on Saturday nights during power blocks. But, with an agenda to complete within the specified timeline, the work has now been extended to weekdays, adhering to strict safety protocols.

The Metro Railway has given the contract to a German company renowned for its extensive experience in manufacturing and replacing Third Rails for over 20 world-class Metros. The replacement project is scheduled for completion within two years. Aluminium third rails have previously been successfully installed on the East-West Metro (Green Line) and the Joka-Taratala stretch of the Purple Line. This technology will also be implemented across all future corridors of the Kolkata Metro.