Historic Change in the Kavi Subhash–Dakshineswar Metro: Infrastructure Transformed After Four Decades

Sanchita Chatterjee, BS News Agency: Not in a single stretch. Metro authorities decided to execute the work on the Kavi Subhash–Dakshineswar corridor—spanning five sections—by breaking it down into two distinct phases. In accordance with this decision, the work was carried out phase by phase and has finally reached completion. Since 1984, the Kolkata Metro has borne witness to a great deal of history. Its routes have gradually lengthened; non-AC coaches have been phased out; and having emerged from beneath the earth, the Metro now reaches for the sky. And now, a major transformation has taken place within this very Metro system. The project, which had been underway for nearly three years, is now complete. After four decades, the Metro's infrastructure has undergone a fundamental change. This transformation has been implemented along the Kavi Subhash–Dakshineswar stretch—specifically, on the Metro's Blue Line. What exactly is this change in the Kolkata Metro?

The steel third rail has been replaced with an aluminum one. The work proceeded in a phased manner over a period of nearly three years. Finally, the project has concluded. In a historic move, Metro engineers have successfully replaced the old steel third rail with an aluminum one across the entire North-South corridor. After four decades, the Kolkata Metro authorities have succeeded in bringing about a major overhaul of the North-South Metro's infrastructure. As mentioned, this was not accomplished in a single operation; the Metro administration decided to divide the work on the Kavi Subhash–Dakshineswar corridor—originally comprising five sections—into two distinct phases. Adhering to this plan, the work was executed in stages, and ultimately, the third rail across the entire corridor has been converted entirely to aluminum. How was this work carried out?

According to Kolkata Metro sources, the work was primarily executed in two phases. The first phase covered the stretch from Mahanayak Uttam Kumar Station (or Tollygunge) to Dum Dum. The second phase extended from the other end of Uttam Kumar Station all the way to Kavi Subhash Station.

The rail replacement work was carried out incrementally, at a rate of 200 meters per day. Unlike steel rails, aluminum rails do not require welding to be joined together; instead, they are connected using separate joint plates.

Meanwhile, Metro services on the East-West corridor and the Joka–Taratala stretch have only recently commenced operations. In this new service, the third rail has been constructed using aluminum right from the outset. However, the North-South Line—specifically the stretch extending from Kavi Subhash to Dum Dum—constitutes the busiest section of the network. Consequently, the decision to replace the four-decade-old steel third rail with an aluminum one in this section is undoubtedly a pioneering move.

**Annual Electricity Savings of One Crore Rupees**

As a result of this upgrade, Metro trains will operate at faster speeds, and the intervals between trains will be reduced. Metro authorities claim that the use of an aluminum third rail will lead to a reduction in electricity wastage of up to 84 percent. This is expected to result in annual electricity savings amounting to one crore rupees. It is projected that the entire cost incurred for this upgrade will be fully recouped through the electricity savings generated within a span of three years.