# Blue Line (Kolkata Metro)

Blue Line, also known as North–South Metro, is a rapid transit metro line of the Kolkata Metro in Kolkata, West Bengal, India. It consists of 26 operational stations from Dakshineswar to Kavi Subhash, out of which 9 of the stations are elevated, 2 are at-grade and the remaining 15 are underground. With a total distance of 32.13 km (19.96 mi), the line connects Dakshineswar and New Garia and uses 5 ft 6 in (1,676 mm) broad gauge tracks. This line was the first underground railway to be built in India, with the first operations commencing in October 1984 and the full stretch that was initially planned being operational by February 1995. On 28 December 2010, Kolkata Metro became the 17th zone of the Indian Railways. Being the country's first, and a completely indigenous process, the construction of the Kolkata Metro Blue Line was more of a trial-and-error affair, in contrast to the Delhi Metro, which has seen the involvement of numerous international consultants. As a result, it took nearly 23 years to completely construct around 15 km (9.3 mi) underground railway from Birpara up to Tollygunge.
It connects Green Line at Esplanade and Orange at Kavi Subhash, and will eventually connect Purple Line at Esplanade and Park Street, Yellow Line at Noapara and Pink Line at Baranagar. Public transport experts have suggested that the line be extended from Dakshineswar to Bally (where it can connect with Howrah Division of Kolkata Suburban Railway) and eventually to Dankuni, an emerging industrial hub of Kolkata metropolitan region.

## History

The laying of the founding stone was done in 1972, but actual construction of Blue Line started only in 1978. Blue Line is 31.38 km (19.50 mi) long with 26 stations (see above). Running of the first metro car on the line by 1984 was considered a great engineering challenge. Former railways minister A. B. A. Ghani Khan Chowdhury took a massive effort to perform it. The first section opened between Esplanade & Bhawanipore (now called Netaji Bhawan). First day Metro Railway Kolkata was started by Sri Tapan Kumar Nath and Sri Sanjay Sil. There were no connections of this stretch with the two depots at Dum Dum & Tollygunge (Now called Mahanayak Uttam Kumar). So metro cars had to be put down on the track near Esplanade by crane, by directly digging the road surface. Initially, only four-car trains were run until 1986. There were no magnetic gates or escalators at that time and ordinary revolving gates served as exits. The Metro too operated on only a single line. Two years later, Blue Line extended up to Tollygunge, at the southern end. At the same time, the metro service was extended to the double line. Magnetic tickets and more entry gates were also introduced at that time. The number of compartments in each train was increased to eight.
Metro service was also started from Dum Dum, at the northern end, to Belgachia in parallel with the extension of the line to the south. But this short portion was not popular and the service was closed down to be restarted when the entire stretch along the north–south corridor was completed.
After 1986 many political incidents hampered the construction, and work almost stopped for nearly six years. After restarting work, the Dum Dum to Shyambazar metro service was started in 1994. This portion was served by four-car trains. Two months later, the Esplanade – Chandni Chowk section was opened and Chandni Chowk – Central section opened three months later. The service from Dum Dum to Tollygunge started in 1995, with Mahatma Gandhi Road metro station, opening in 1996. During this time, more magnetic gates and escalators were added and the revolving gates were slowly phased out.
In 2009, a large number of stations on Blue Line were renamed by then Minister of Railways Mamata Banerjee.
On 22 February 2021, the Noapara – Dakshineswar stretch was inaugurated by Prime Minister Narendra Modi.
On 21 July 2024, the entire stretch from Dakshineswar to Kavi Subhash, crossed 1.92 lakh passenger mark for the first time on a single day.

## Timeline

The following dates represent the dates the section opened to the public, not the private inauguration.
History :
| Extension date | Terminals | Terminals | Length |
| 24 October 1984 | Esplanade | Bhowanipore | 3.40 kilometers (2.11 mi) |
| 12 November 1984 | Dum Dum | Belgachhia | 2.15 kilometers (1.34 mi) |
| 29 April 1986 | Bhowanipur (now Netaji Bhavan) | Tollygunge (now Mahanayak Uttam Kumar) | 4.24 kilometers (2.63 mi) |
| 13 August 1994 | Belgachhia | Shyambazar | 1.63 kilometers (1.01 mi) |
| 2 October 1994 | Esplanade | Chandni Chowk | 0.71 kilometers (0.44 mi) |
| 19 February 1995 | Shyambazar | Girish Park | 1.92 kilometers (1.19 mi) |
| 19 February 1995 | Chandni Chowk | Central | 0.60 kilometers (0.37 mi) |
| 27 September 1995 | Central | Girish Park | 1.80 kilometers (1.12 mi) |
| 22 August 2009 | Tollygunge (Mahanayak Uttam Kumar) | Garia Bazar (now Kavi Nazrul) | 5.85 kilometers (3.64 mi) |
| 7 October 2010 | Garia Bazar (now Kavi Nazrul) | New Garia (now Kavi Subhash) | 3.00 kilometers (1.86 mi) |
| 10 July 2013 | Dum Dum | Noapara | 2.09 kilometers (1.30 mi) |
| 22 February 2021 | Noapara | Dakshineswar | 4.1 kilometers (2.5 miles) |
| Total | Dakshineswar | New Garia (now Kavi Subhash) | 31.3 kilometers (19.4 mi) |

## Stations

The stations of this Line are:
Blue Line :
| # | Station Name | Station Name | Location | Phase | Opening | Connections | Layout | Platform Type | Depot | Coordinates | Notes |
| # | English | Bengali | Location | Phase | Opening | Connections | Layout | Platform Type | Depot | Coordinates | Notes |
| 1 | Dakshineswar | দক্ষিণেশ্বর | Dakshineswar | 7 | 22nd Feb 2021 | Dakshineswar Dakshineswar Bus Stand Alambazar More bus Stop Ma Bhabotarini Jetty Ghat | Elevated | Side | Noapara Depot Tollygunge Depot New Garia Depot | | |
| 2 | Baranagar | বরানগর | Baranagar | 7 | 22nd Feb 2021 | Pink Line • Baranagar (Planned) ---- Baranagar Road Dunlop Bus Stand | Elevated | Side | Noapara Depot Tollygunge Depot New Garia Depot | 22°37′23″N 88°25′38″E﻿ / ﻿22.62306°N 88.42722°E﻿ / 22.62306; 88.42722 | Also known as Dunlop Crossing |
| 3 | Noapara | নোয়াপাড়া | Noapara | 6 | 10 July 2013 | Yellow Line • Noapara (U\C) ---- 34C Bus Stand Health More Bus Stop Gharui Paschimpara Bus Stop | Elevated | Side | Noapara Depot Tollygunge Depot New Garia Depot | | |
| 4 | Dum Dum | দমদম | Dum Dum Junction railway station | 1B | 12th Nov 1984 | Dum Dum Jn Dum Dum Station Bus Stop | Elevated | Side | Noapara Depot Tollygunge Depot New Garia Depot | | |
| 5 | Belgachia | বেলগাছিয়া | Belgachia | 1B | 12th Nov 1984 | Belgachia Bus Depot Belgachia Metro Bus Stop Belgachia More Bus Stop | Underground | Island | Noapara Depot Tollygunge Depot New Garia Depot | | |
| 6 | Shyambazar | শ্যামবাজার | Shyambazar | 3A | 15th Feb 1995 | Shyambazar Tram Depot Shyambazar Metro Bus Stop Shyambazar 5 Point Bus Stop Shyambazar Bus Stand | Underground | Island | Noapara Depot Tollygunge Depot New Garia Depot | | |
| 7 | Shobhabazar Sutanuti | শোভাবাজার সুতানুটি | Shobhabazar | 3A | 15th Feb 1995 | Shobhabazar Metro Bus Stop Jaipuria College Bus Stop | Underground | Island | Noapara Depot Tollygunge Depot New Garia Depot | | |
| 8 | Girish Park | গিরিশ পার্ক | Jorasanko | 3A | 15th Feb 1995 | Girish Park Bus Stop | Underground | Island | Noapara Depot Tollygunge Depot New Garia Depot | | Also known as Jorasanko |
| 9 | Mahatma Gandhi Road | মহাত্মা গান্ধী রোড | Burrabazar | 3B | 27th Sep 1995 | Mahajati Sadan Bus Stop Ram Mandir Bus Stop Muhammad Ali Park Bus Stop Muhammad Ali Park Tram Stop | Underground | Island | Noapara Depot Tollygunge Depot New Garia Depot | | Also known as Mahajati Sadan |
| 10 | Central | সেন্ট্রাল | Bowbazar | 3A | 15th Feb 1995 | Central Avenue Bus Stop Central Metro Station Bus Stop School of Tropical Medicine Bus Stop Medical College Bus Stop | Underground | Island | Noapara Depot Tollygunge Depot New Garia Depot | | Also known as Bowbazar |
| 11 | Chandni Chowk | চাঁদনি চক | Chandni Chowk | 3A | 15th Feb 1995 | Chandni Chowk Bus Stop Victoria House Bus Stop | Underground | Island | Noapara Depot Tollygunge Depot New Garia Depot | | |
| 12 | Esplanade | এসপ্ল্যানেড | Dharmatala | 1A | 24th Oct 1984 | Purple Line • Esplanade (U\C) Green Line • Esplanade ---- Esplanade Tram Depot Esplanade Bus Terminus (WBTC, CTC, SBSTC, NBSTC) | Underground | Island | Noapara Depot Tollygunge Depot New Garia Depot | | International Bus Terminus. Also known as Dharmatala / Chowringhee |
| 13 | Park Street | পার্ক স্ট্রীট | Park Street | 1A | 24th Oct 1984 | Purple Line • Park Street (U/C) ---- Park Street Bus Stop | Underground | Side | Noapara Depot Tollygunge Depot New Garia Depot | | Also known as Mother Teresa Sarani |
| 14 | Maidan | ময়দান | Maidan | 1A | 24th Oct 1984 | Maidan Bus Stop | Underground | Island | Noapara Depot Tollygunge Depot New Garia Depot | | |
| 15 | Rabindra Sadan | রবীন্দ্র সদন | Rabindra Sadan | 1A | 24th Oct 1984 | Exide More Bus Stop Rabindra Sadan Bus Stop Chowringhee Road-Calcutta Club Bus Stop | Underground | Island | Noapara Depot Tollygunge Depot New Garia Depot | | Also known as Exide |
| 16 | Netaji Bhavan | নেতাজি ভবন | Bhawanipore | 1A | 24th Oct 1984 | Netaji Bhawan Bus Stop Jadu Babur Bazar Bus Stop | Underground | Island | Noapara Depot Tollygunge Depot New Garia Depot | | Also known as Bhawanipore |
| 17 | Jatin Das Park | যতীন দাস পার্ক | Hazra Junction | 2 | 29 April 1986 | Hazra Bus Stop Jatin Das Park Bus Stop Sujata Sadan Bus Stop | Underground | Island | Noapara Depot Tollygunge Depot New Garia Depot | | Also known as Hazra |
| 18 | Kalighat | কালীঘাট | Kalighat | 2 | 29 April 1986 | Rasbehari Crossing Tram Stop Rashbehari Crossing Bus Stop Rashbehari Gurudwara Bus Stop | Underground | Island | Noapara Depot Tollygunge Depot New Garia Depot | | Also known as Rashbehari |
| 19 | Rabindra Sarobar | রবীন্দ্র সরোবর | Rabindra Sarobar | 2 | 29 April 1986 | Tollygunge Charu Market Tram Stop Rabindra Sarobar Bus Stop Bhabani Cinema Bus Stop | Underground | Island | Noapara Depot Tollygunge Depot New Garia Depot | | Also known as Charu Market |
| 20 | Mahanayak Uttam Kumar | মহানায়ক উত্তম কুমার | Tollygunge | 2 | 29 April 1986 | Tollygunge Tram Depot Tollygunge Bus Depot Tollygunge Tram Depot Bus Stop | At Grade | Both side & island | Noapara Depot Tollygunge Depot New Garia Depot | | Also known as Tollygunge |
| 21 | Netaji | নেতাজি | Kudghat | 4 | 22nd Aug 2009 | Kudghat Bus Stand | Elevated | Side | Noapara Depot Tollygunge Depot New Garia Depot | | Also known as Kudghat |
| 22 | Masterda Surya Sen | মাস্টারদা সূর্য সেন | Bansdroni | 4 | 22nd Aug 2009 | Bansdroni Bus Stand | Elevated | Side | Noapara Depot Tollygunge Depot New Garia Depot | | Also known as Bansdroni |
| 23 | Gitanjali | গীতাঞ্জলি | Naktala | 4 | 22nd Aug 2009 | Rathtala Bus Stop Naktala Minibus Stand Bunty Cinema Bus Stop | Elevated | Side | Noapara Depot Tollygunge Depot New Garia Depot | | Also known as Naktala |
| 24 | Kavi Nazrul | কবি নজরুল | Garia | 4 | 22nd Aug 2009 | Garia Metro Bus Stop Garia More Bus Stop Garia Bazar Bus Stop Garia 6 Number Bus Stand Garia 5 Number Bus Stand | Elevated | Side | Noapara Depot Tollygunge Depot New Garia Depot | | Also known as Garia Bazar |
| 25 | Shahid Khudiram | শহিদ ক্ষুদিরাম | Briji | 5 | 7th Oct 2010 | Khudiram Metro Bus Stop Dhalai Bridge Bus Stop | Elevated | Side | Noapara Depot Tollygunge Depot New Garia Depot | | Also known as Dhalai Bridge |
| 26 | Kavi Subhash | কবি সুভাষ | New Garia | 5 | 7th Oct 2010 | Orange Line • Kavi Subhash ---- New Garia New Garia Bus Stand | At Grade | Side | Noapara Depot Tollygunge Depot New Garia Depot | | Also known as New Garia |

### Alignment & interchanges

Dakshineswar, Baranagar, Dum Dum, Noapara, Park Street, Mahanayak Uttam Kumar, Netaji, Masterda Surya Sen, Gitanjali, Kavi Nazrul, Shahid Khudiram and Kavi Subhash have side platforms; all other stations have island platforms. Mahanayak Uttam Kumar is an exception as it has both platforms on the sides as well as in the centre. Dakshineswar, Baranagar, Dum Dum, Rabindra Sarobar & Kavi Subhash have connections to interchange with Kolkata Suburban Railway. Shyambazar, Mahatma Gandhi Road, Esplanade, Kalighat, Rabindra Sarobar & Mahanayak Uttam Kumar stations have connections to the tram network. EM Bypass can be accessed from the Shahid Khudiram metro station and Kavi Subhash metro station.

### Extension up to New Garia (2010)

Mamata Banerjee during her first tenure as the railway minister initiated the project of Tollygunge – Garia metro extension. During her second tenure (2009–2011) she inaugurated the extension, and also introduced new Air Conditioned rakes, manufactured indigenously at the Integral Coach Factory.
The new extension to Garia Bazar in the south opened to the public on 23 August 2009. The Garia Bazar station was named after Kavi Nazrul. A final extension, in the southern end, from Kavi Nazrul (Garia Bazar) to Kavi Subhash (New Garia) was inaugurated on 7 October 2010, bringing the total number of stations to 23. On the same day, two Air-Conditioned rakes were also pressed into service.

### Extension up to Noapara (2013) and Dakshineswar (2021)

The line was extended up to Noapara from Dum Dum on 10 July 2013. The line was further extended from Noapara to Dakshineswar (4.1 km) is now complete & operational. It will be met by a metro line from Barrackpore at Baranagar (12.5 km). Trial runs for this stretch started on 23 December 2020, after delay due to COVID-19 pandemic. The stretch was inaugurated on 22 February 2021 & commercial operations began from the following day.
The stations on this stretch are :
* Noapara
* Baranagar
* Dakshineswar

## Features
### Technical features

Metro construction is of a very complex nature requiring the application of several new technologies in the fields of civil, electrical, signaling and telecommunication engineering. Indian engineers backed by their own experience and supplemented by their studies abroad adopted advanced technologies in the following fields for the first time in India.
* Cut and cover method of construction using diaphragm walls and sheet piles.
* Use of extensive decking to keep the traffic flowing over the cut while construction is in progress underneath.
* Shield tunneling using compressed air and airlocks.
* Ballastless track using elastic fastenings, rubber pads, epoxy mortar and nylon inserts.
* Air-conditioning and ventilation system for environmental control of stations and tunnels.
* Third Rail current collection system for traction.
* Underground substations with dry-type transformers and SF$_6$ circuit breakers.
* Tunnel-Train VHF-radio communication system.
* Microprocessor-based train control and supervisory remote control system for substations.
* Automatic ticket vending and checking system.

### Salient features

| Total route length | 32.13 km (19.96 mi) |
| Stations | 26 (15 underground, 2 on the surface and 9 elevated) |
| Gauge | 1,676 mm (5 ft 6.0 in), Indian Broad Gauge |
| Cars per train | 8 |
| Maximum permissible speed | 80 km/h (50 mph) |
| Average speed | 30–31 km/h (18.6–19.3 mph) |
| Voltage | 750 V D.C. |
| Method of current collection | Third Rail |
| Travel Time: Dakshineswar to Kavi Subhash | 62 minutes (approx.) |
| Headways | Average 10 minutes |
| Total estimated cost of the project | ₹18.25 billion (US$208.9 million) (approx.) |
| Environment control | Air condtioners are used in all trains. |

### Proposed Feature and Expansion

Platform Screen Doors (PSDs) are a system of full height/half height motorized sliding doors that provide controlled access to the trains and protect the platform edge. PSD work is proposed for all stations in this line to minimize suicidal cases common in this route. This plan was proposed after the successful utilization of Platform Screen Doors to keep the number of suicidal cases on the Green Line to absolute zero.
Metro Railway also plans to extend the platform and viaduct of Dakshineswar metro station by ~90 m (300 ft) via erection of two new pillars beyond the current length to facilitate a crossover so that the trains can switch tracks faster in order to increase the frequency of services to the Noapara–Dakshineswar stretch.

## Rolling stock
### CRRC Dalian

There was a need to replace non-AC rakes on Blue line and so during mid 2015 it was announced that Indian Railways for the first time would rope an international train-maker, China Railway Rolling Stock Corporation (CRRC) based in Dalian. As per the tender, 14 new rakes composed of 8 coaches each will be supplied to Kolkata Metro by CNR Dalian, a subsidiary of CRRC Dalian, which will be running on Blue Line. These rakes will be of ultra-modern technology. They will have doors that will be 20 cm (7.9 in) wider than any other metro rails in India. They will have wide vestibules, 2 feet 6 inches (0.76 m) wider than the existing trains. The design consists of the aerodynamic front with large doors and LED Lights, and violet colored stripe on silver color body. These rakes are capable of a top speed of 80 km/h (50 mph). The first of the 14 rakes from Chinese firm Dalian was slated to arrive by December 2017 but got delayed due to various reasons. The first rake finally arrived in Kolkata on 3 March 2019 on a vessel at Netaji Subhash dock of Kolkata port. Each of the 8 coaches of the rake weigh nearly 45 tonnes. The rake was unloaded and taken to Noapara Carshed, after which trial runs and inspection would be carried out before commencing operations. Other 13 rakes are ready, but the shipment got delayed due to the ongoing coronavirus pandemic.
These rakes were under performance trials for more than 20 months as serious problems related to performance of the rake were identified during trials. Some of the issues related to insufficient power to climb up the slopes in the tunnels and higher oscillation in the bogie.
On 17 March 2023, the first Dalian rake was inducted into service. Another 3 rakes will arrive soon.

### Old fleet

The whole fleet is vestibuled. Carbodies and mechanical components were made by ICF with electrical components made by NGEF, Bangalore. The fleet is unique in that it is the only railroad equipment in India with end-mounted cab doors (except for some of the WAG-6 series locomotives).
ICF has specifically designed, manufactured and supplied these cars for the first underground railway system. The special features incorporated are:
* Traction power supply through third rail current collection system.
* Automatic door opening/closing and continuous monitoring of the transit.
* Automatic Train Stop (ATS) system which will automatically apply the brakes in case of human failure.
* Automatic train operation (ATO) with the driver acting as the train supervisor (optional).
* A public address system is provided on the trains to announce approaching stations. A central dispatcher can contact any of the train crew and also make important announcements directly to passengers over the system.
With all these features, the design and manufacturing process of these cars to a very high standard of reliability and safety has been a challenge. This was achieved without any technical collaboration.

## Reservation for women

In 2008, the Kolkata Metro Railway experimented with the practice of reserving two entire compartments for women.
This system was found to be ineffective and caused inconvenience for a lot of commuters (including women) and the plan was eventually dropped by the metro authority. But a certain section of seats in each of the eight compartments is reserved for women.

## Problems with this line

The founder of Delhi Metro, E. Sreedharan said Indian Railways are not experts at urban transport, and misplanned the Kolkata metro from the beginning. A private company should run the metro and can bring it up to standard in five years.
Since Kolkata Metro is under Indian Railways, it can't take its own independent decisions. It has to rely on Indian Railways for everything (like rakes etc.). The rakes are ordered directly from ICF without floating any global tenders.