STN: The Kolkata Metro Blue Line is set for a major upgrade after the central government approved Rs 671.7 crore for improvement work on this busy metro corridor. The project aims to improve train frequency, increase speed, and reduce crowding for daily commuters.
The Kolkata Metro Blue Line is the oldest metro corridor in India and remains the busiest route in the city. Around 6 lakh passengers use this line every day. With rising passenger numbers, the current system is under pressure, especially during peak office hours.
Officials believe this upgrade will help improve daily travel for lakhs of commuters by cutting waiting times and making train movement smoother.
Kolkata Metro Blue Line Upgrade Project Details
Here is a quick look at the project:
| Details | Information |
|---|---|
| Corridor | Kolkata Metro Blue Line |
| Upgrade Cost | Rs 671.7 crore |
| Total Rail Project Approval | Rs 895.3 crore |
| Daily Passengers | Around 6 lakh |
| Main Upgrades | Power system, CBTC signalling, third rail replacement |
| Current Train Gap | 5 minutes |
| Planned Train Gap | 2.5 minutes |
The metro line started operations over 40 years ago. It was built for a much smaller number of passengers. Over time, the number of daily commuters has grown sharply.
Today, crowded platforms and packed trains have become common. Metro authorities now want to increase train frequency so passengers can travel with less waiting.
Major Work Planned for Kolkata Metro Blue Line
A major part of the project focuses on upgrading the power system.
The planned work includes:
- Seven new traction substations worth Rs 297 crore
- Modernisation of older substations
- Power supply upgrade from 11 KV to 33 KV
- Better power support between Esplanade and New Garia
- Improvement work on elevated sections between Netaji and Kavi Subhas
Metro officials said many existing systems have become old. Spare parts are also becoming harder to source.
The railway will also replace the current steel third rail with aluminium rails. Aluminium conducts electricity better. This can reduce power loss and improve train performance.
Officials expect trains to accelerate faster after this upgrade.
Most underground sections are already covered under earlier upgrade work. The next phase will focus on the elevated stretch between Tollygunge and New Garia.
Kolkata Metro Blue Line to Get Advanced Signalling System
The Kolkata Metro Blue Line currently uses the older TPWS signalling system.
Metro Railway now plans to install Communication-Based Train Control (CBTC), which is a more advanced signalling system.
This technology allows trains to run safely at shorter intervals. That means more trains can operate on the same route without affecting safety.
At present, trains run every five minutes on most sections. After the upgrade, the gap could reduce to 2.5 minutes.
Officials also said the system may eventually support train intervals of just 90 seconds in the future.
This change could make a big difference for daily commuters.
Speed Increase Planned on the Corridor
Train speed is also expected to improve.
Currently, trains on most sections of the Blue Line run at a top speed of 55 kmph.
Only the Noapara to Dakshineswar stretch allows trains to run at 80 kmph.
Metro officials now plan to increase speed on more sections after the upgrade work is complete.
Faster trains will help reduce travel time across the corridor.
Kavi Subhas Station Reconstruction Work
The southern end of the line has faced operational issues since July 2025.
Cracks appeared on a platform at Kavi Subhas metro station, which affected normal train movement.
Since then, trains have only been operating up to Shahid Khudiram station on that side.
Metro Railway plans to begin reconstruction work at Kavi Subhas soon.
Once the station reopens fully, commuters using the southern stretch will benefit from smoother services.
What This Upgrade Means for Commuters
For daily passengers, this project could bring practical benefits.
These include:
- Less crowding during peak hours
- Shorter waiting time on platforms
- Faster journeys
- Better service reliability
- Improved passenger safety through modern signalling
The Kolkata Metro Blue Line remains a key part of public transport in the city. This upgrade could help prepare the corridor for future passenger growth.
FAQs
A: Metro Railway has announced the approval, but the full completion timeline has not been officially confirmed yet.
A: CBTC is a signalling system that helps trains communicate in real time. It improves safety and allows trains to run closer together.
A: The Kolkata Metro Blue Line is India’s oldest metro corridor, with operations starting in the 1980s.
A: Officials have not announced any fare changes linked to this project.
A: The Blue Line connects Dakshineswar in the north to Kavi Subhas in the south.