Kolkata Metro Railway has completed the aluminium third rail upgrade across the underground section of the Blue Line, marking a major infrastructure modernisation milestone aimed at improving operational efficiency and increasing train frequency.
The upgrade has been carried out between Dum Dum and Mahanayak Uttam Kumar stations, covering the underground stretch of the city’s oldest metro corridor.
According to officials, the conventional steel third rail system has been replaced with an advanced aluminium stainless steel composite third rail. The new system offers lower electrical resistance, improved energy efficiency, better current-carrying capacity, and reduced power losses compared to traditional steel-based infrastructure.
The modernisation project is expected to play a critical role in supporting a future train headway of 150 seconds, enabling Kolkata Metro to operate services at much shorter intervals and accommodate rising passenger demand across the busy corridor.
Officials stated that the upgraded system will ensure more stable power supply to trains, improve operational reliability, and support higher-frequency services without compromising safety or performance.
The Blue Line remains one of the most heavily used urban transit corridors in Kolkata, connecting major residential, commercial, and institutional zones across the city. Increasing train frequency is expected to significantly improve passenger movement and reduce platform crowding during peak hours.
The aluminium third rail technology is already used in several modern metro systems globally due to its efficiency, durability, and lower maintenance requirements. Railway officials noted that the transition aligns Kolkata Metro with international urban transit standards and future-ready railway infrastructure practices.
Apart from improving operational performance, the upgrade is expected to contribute to long-term energy savings and lower maintenance costs while enhancing the overall reliability of the metro network.
The completion of the project forms part of broader efforts to modernise Kolkata Metro’s infrastructure as multiple metro expansion projects continue across the city. Kolkata is currently witnessing large-scale investments in new metro corridors, signalling systems, rolling stock upgrades, and multimodal urban transport integration.
Officials highlighted that higher-frequency operations supported by the upgraded power supply system will strengthen the metro’s role as a sustainable and efficient public transportation mode for the city’s growing commuter base.
Industry experts believe the successful completion of the aluminium third rail upgrade will help Kolkata Metro improve network capacity, operational flexibility, and passenger convenience while supporting future ridership growth and urban mobility requirements across the metropolitan region.
