Kolkata Metro's Oldest Line Gets a ₹500 Crore HVAC Upgrade

Kolkata Metro Railway will invest ₹500 crore to modernise the ageing air-conditioning and ventilation systems along the 16.9 km Rabindra Sarobar–Belgachhia section of the North-South (Blue) Line.

The upgrade will cover 15 underground stations, replacing outdated Environmental Control Systems (ECS) with state-of-the-art HVAC technology. The initiative aims to enhance passenger comfort by delivering improved cooling across platforms, concourses, and tunnels, while also boosting fire safety and evacuation efficiency through an upgraded twin tunnel ventilation system—critical amid rising ambient temperatures.

The existing centralised air-conditioning systems, which include water-cooled chillers, cooling towers, coils, and ducting, will be replaced with modern, energy-efficient alternatives. Metro officials highlighted that the overhaul will not only improve thermal comfort but also ensure greater operational reliability during emergencies.

Launched in 1984 with the 3.4 km Esplanade–Bhowanipore section, the Blue Line is India’s first underground metro and now spans 30 km, running from Dakshineswar to Shaheed Khudiram. However, services have been truncated to Dhalai Bridge since 28 July, following structural concerns at the Kavi Subhash terminal, where cracks were detected in supporting columns.

The tendering process is underway, marking a critical step in revitalising Kolkata’s oldest metro corridor and aligning it with modern infrastructure standards.

News by Rahul Yelligetti.