Kolkata Metro To Upgrade AC And Tunnel Ventilation In Rs 500 Crore Eco-Friendly Overhaul

Kolkata Metro Railway has rolled out a Rs 500 crore initiative to modernise the air-conditioning and tunnel ventilation systems along the 16 km Belgachhia–Rabindra Sarobar stretch, introducing green technology aimed at conserving 18 crore litres of groundwater each year, according to a Times of India