Circle MRT Line

CCL  Circle MRT Line Laluan MRT Bulatan 地铁环线 இணைப்பு எம்ஆர்டி வழி
The Circle Line is coloured orange on system maps.
Overview
Type	Rapid transit
System	Mass Rapid Transit (Singapore)
Status	Operational Under planning (Stage 6)
Termini	Dhoby Ghaut HarbourFront Marina Bay
Stations	33 (excluding Bukit Brown)
Services	3
Daily ridership	398,000 (May 2015)
Operation
Opened	28 May 2009 (Stage 3) 17 April 2010 (Stage 1 and 2) 8 October 2011 (Stage 4 and 5) 14 January 2012 (Circle Line Extension) 2025 (Stage 6)
Owner	Land Transport Authority
Operator(s)	SMRT Trains (SMRT Corporation)
Character	Underground
Depot(s)	Kim Chuan
Rolling stock	C830, C830C
Technical
Line length	35.5 km (22.1 mi)
Track gauge	1,435 mm (4 ft 8 ^1⁄2 in) standard gauge
Electrification	750 V DC third rail
Operating speed	limit of 78 kilometres per hour (48 mph)
Route map Legend ■ Jurong East   ■ HarbourFront   ■ Punggol  CC1  NS24  NE6  Dhoby Ghaut     ■ Chinatown  CC2  Bras Basah  CC3  Esplanade  CE2  NS27  TE20  Marina Bay ■ Marina South Pier    CE1  DT16  Bayfront  CC4  DT15  Promenade ■ Bukit Panjang    CC5  Nicoll Highway Kallang Basin  CC6  Stadium  CC7  Mountbatten  CC8  Dakota Geylang River  CC9  EW8  Paya Lebar ■ Pasir Ris   ■ Joo Koon Pan Island Expressway Kallang–Paya Lebar Expressway  CC10  DT26  MacPherson ■ Sungei Bedok   ■ Bukit Panjang  CC11  Tai Seng Kim Chuan Depot  CC12  Bartley ■ Punggol   ■ HarbourFront  CC13  NE12  Serangoon  CC14  Lorong Chuan Central Expressway  CC15  NS17  Bishan ■ Jurong East   ■ Marina South Pier  CC16  Marymount ■ Woodlands North    CC17  TE9  Caldecott   ■ Sungei Bedok    CC18  Bukit Brown Pan Island Expressway ■ Bukit Panjang   ■ Sungei Bedok  CC19  DT9  Botanic Gardens  CC20  Farrer Road  CC21  Holland Village ■ Joo Koon   ■ Pasir Ris  CC22  EW21  Buona Vista  CC23  one-north Ayer Rajah Expressway  CC24  Kent Ridge  CC25  Haw Par Villa  CC26  Pasir Panjang  CC27  Labrador Park  CC28  Telok Blangah  CC29  NE1  HarbourFront   ■ Punggol    CC30  Keppel  CC31  Cantonment  CC32  Prince Edward

The Circle Line (CCL) is Singapore's fourth Mass Rapid Transit line. This fully underground line is 35.5 kilometres (22.1 mi) long with 30 stations (excluding Bukit Brown) and is fully automatically operated.^[1] It takes about one hour to travel from one end to the other. The line is coloured yellow^[2] on the rail map.

As the name implies, the line is an orbital circle route linking all radial routes leading to the city. It also covers many parts of the Central Area. From Promenade, the line branches with one branch terminating at Dhoby Ghaut and the other terminating at Marina Bay. Transfers to the North South Line are provided at Bishan, Dhoby Ghaut and Marina Bay, East West Line at Paya Lebar and Buona Vista, and North East Line at Dhoby Ghaut, Serangoon and HarbourFront. The Downtown Line interchanges with the Circle Line at Bayfront, Promenade and Botanic Gardens. Future sections of the Downtown Line will interchange with the line at MacPherson. The future Thomson-East Coast Line will interchange with the Circle Line at Caldecott and Marina Bay.

The Circle Line is the first medium capacity line in Singapore. As a medium capacity line, each Circle Line train has only three cars instead of the six-car configuration as seen on other currently operating MRT lines excluding the Downtown Line. As of May 2015, the daily ridership is 398,000.^[3] The line reduces travelling time for commuters by allowing them to shorten trips between north and east or north and west, bypassing busy interchange stations like City Hall and Raffles Place.

On 8 October 2011, the Circle Line became fully operational to commemorate its operator SMRT's 24th Anniversary of Rail Services since the company's establishment in 1987.

History

Plans for the Circle Line date back to the 1980s. The then Minister for Communications and Information, Dr Yeo Ning Hong stated that such a system "would be feasible when the population reaches four million."

The Circle Line was first known as the Marina Line in May 1998. The Marina Line was initially planned as a 12-station underground line, starting from Chinatown and Dhoby Ghaut via the National Stadium to either Kallang or Paya Lebar station. However, the Chinatown leg was later truncated and was reduced to 6 stations up to Stadium station. On the other hand, a further extension towards Upper Paya Lebar was added in the year 2000. The Marina Line was also merged with an LRT line that goes from Paya Lebar to Buona Vista via Serangoon and Bishan to form Circle Line Stage 3 and 4 in 2001. Circle Line Stage 5 was finalised in February 2002 when Stage 4 was extended from Buona Vista to World Trade Centre to close up the link and to provide connectivity from the west to Sentosa, and it became the full Circle Line in the end. Stations in Circle Line that were a part of the original Marina Line plans include Dhoby Ghaut, Bras Basah, Esplanade, Promenade, Nicoll Highway and Stadium. Also, the part of the Marina Line from Chinatown to Promenade is now part of the Downtown Line.

Construction started in April 2002, and was supposed to be opened from 2006 and fully opened in 2010, with an estimated cost of S$6.7 billion, the Nicoll Highway collapse caused the construction of the Circle Line to be delayed to open from 28 May 2009 (the Stage 3 of which it is not affected by Nicoll Highway collapse), with full opening on 8 October 2011, at an escalated cost of nearly S$10 billion.^[4] Due to the re-alignment of the Nicoll Highway Station to a new location, the station is only two-thirds the size of the original plan before the collapse, and located 100 metres (330 ft) away from the highway collapse site.^[5] The decision was also made to open both Caldecott, and Haw Par Villa stations (previously Thomson and West Coast), as a normal stations leaving the Bukit Brown MRT Station closed, and there is only a middle track and emergency escape shaft.

View of underground platform at Bishan Station of the Circle Line from ground level during construction in 2007.

Stage 3, a 5 kilometres (3.1 mi) five-station segment stretching from Bartley to Marymount, was the first section of the line opened, on May 28, 2009. Initial ridership on this section was lower than estimated, at 32,000 passengers per day (ppd) instead of the estimated 55,000 ppd.^[6] Tunneling works for the entire line were completed on August 17, 2009.^[7] Stages 1 and 2 started operations on April 17, 2010,^[8] Stages 4 and 5 on October 8, 2011,^[9] and the final Circle Line Extension on January 14, 2012. The line was also fully completed in October 2011, to commemorate operator SMRT's 24th anniversary.

one-north Station on the Circle Line.

Circle Line Stage 6

On 17 January 2013, the Land Transport Authority (LTA) announced 'Circle Line Stage 6' which will finally close the circle, running between Marina Bay and HarbourFront. This extension will help commuters who want to go from Harbourfront to Marina Bay or vice versa. It will be a 4 km extension.^[10] On 29 October 2015, the LTA announced the 3 station locations for the 'Circle Line Stage 6'. The stations are Keppel Station, Cantonment Station and Prince Edward Station. Tenders will be called for construction in 2016 and demolition, diversion and utility works will commence in 2017. Construction of the line will begin earliest in 2018 and it is due for completion in 2025.^[11] When the three CCL6 stations: Keppel, Cantonment and Prince Edward are completed in 2025, the CCL will have a total of 33 stations, including 12 interchange stations with other MRT lines.

Incidents

Nicoll Highway collapse

On 20 April 2004, a section of the tunnel being built for the Circle Line collapsed, apparently when a retaining wall used in the tunnel's construction gave way. This occurred near what was planned to become the Nicoll Highway Station on the Circle line, not far from the Merdeka Bridge. The accident left a collapse zone 150 metres (490 ft) wide, 100 metres (330 ft) long, and 30 metres (98 ft) deep. Four workers were killed, with three more injured.

A criminal inquiry found the main contractor Nishimatsu Construction Company and joint venture partner firm Lum Chang Construction Company and their officers, as well as key Land Transport Authority officers responsible for the collapse. Several other officers and subcontractors were reprimanded and issued warnings in connection with the accident.

As a result of this accident, the first phase of the Circle Line, previously scheduled to open in 2008, was completed in 2009 instead. The affected station has been shifted about 100 metres (330 ft) away from the accident site and is now located at Republic Avenue.

This accident had also resulted in stricter safety regulations for the construction of all future MRT lines. The shifting of the Nicoll Highway Station also meant it can no longer serve as a terminus for the Bukit Timah Line, partially influencing the creation of the current Downtown Line.

Other incidents

On 16 August 2007, the Building and Construction Authority (BCA) issued a stop-work order and revoked the contractor's tunnelling permit after a 7 metres (23 ft) stretch of two lanes sank about 20 centimetres (7.9 in), close to the junction of Telok Blangah Road and Alexandra Road in the evening, resulting in a halting of tunnelling works.^[12]

A section of the road above a construction site near Holland Road caved in on the morning of 24 May 2008, creating a massive hole. The hole, directly in front of two private houses along Cornwall Gardens Road, measured 8 by 7 metres and was 3 metres deep. No one was injured, but the road was temporarily closed to traffic.^[13]

Line disruptions

On 20 September 2011, a power fault disrupted train services on all 16 stations on the Circle Line. The four hours delay left thousands of commuters stranded during rush-hour. It was reported that leaks and a damaged cable along the Circle Line were the caused of the disruption.^[14] The disruption started at about 5.30 am. Train services were gradually restored from 8am and all services were restored just before 10am. Dakota and Mountbatten stations were the last two to resume operations.^[15] Investigations were carried out. It was later found that a faulty cable beneath the platform level at Dakota Station caused a power fault on Tuesday morning that affected train services at all 16 stations on the Circle Line.^[16] 27,000 passengers were affected by the disruption during the four hours delay, with bus bridging services plying the Circle Line route.^[17]

Starting in late August 2016, intermittent signal interference led to a five-day series of train disruptions, which reappeared in November.^[18][19] A team of data scientists explored the data and discovered via a Marey Chart visualization that it was caused by hardware problems sending errant signals from a "rogue" train, PV46.^[20][21]

Stations

Alstom Metropolis C830 rolling stock for the Circle Line parked in the depot.

The map of the Circle Line shown on top of the train doors in 2012. A newer version with the current LTA font has since replaced them.

Interior of CCL MRT Alstom Metropolis C830 train

The main route goes between Dhoby Ghaut and HarbourFront, with a branch line between Marina Bay and Stadium. Its train frequency is 5 minutes during off-peak, and 2.5 minutes during peak hours, the branch line is being extended to HarbourFront during peak hours and several extended/free travel rides (National Day, New Year's Eve, F1 weekend).

Station Number	Station Name	Interchange/Notes
CC1  NS24  NE6	Dhoby Ghaut	Change for the North South Line or North East Line
CC2	Bras Basah
CC3	Esplanade
CC4  DT15	Promenade	Change for the Downtown Line Change for train services towards CE1 Bayfront or CE2 Marina Bay
CC5	Nicoll Highway
CC6	Stadium	Marina Bay shuttle terminus during off-peak hours
CC7	Mountbatten
CC8	Dakota
CC9  EW8	Paya Lebar	Change for the East West Line
CC10  DT26	MacPherson	Change for the Downtown Line (2017)
CC11	Tai Seng
CC12	Bartley
CC13  NE12	Serangoon	Change for the North East Line
CC14	Lorong Chuan
CC15  NS17	Bishan	Change for the North South Line
CC16	Marymount
CC17  TE9	Caldecott	Change for the Thomson-East Coast Line (2020)
CC18	Bukit Brown	Closed until further notice; Reserved station; Not in operation
CC19  DT9	Botanic Gardens	Change for the Downtown Line
CC20	Farrer Road
CC21	Holland Village
CC22  EW21	Buona Vista	Change for the East West Line
CC23	one-north
CC24	Kent Ridge
CC25	Haw Par Villa
CC26	Pasir Panjang
CC27	Labrador Park
CC28	Telok Blangah
CC29  NE1	HarbourFront	Change for the North East Line
Stage 6 (Under planning) (Completion by 2025)
CC30	Keppel
CC31	Cantonment
CC32	Prince Edward
Circle Line Extension
CE1  DT16	Bayfront	Change for the Downtown Line
CE2  NS27  TE20	Marina Bay	Change for the North South Line or Thomson-East Coast Line (2021)

Rolling stock

The rolling stock consists of 40^[22] Alstom Metropolis C830 trains^[23] running in three-car formation. They are stabled at Kim Chuan depot, the world's largest underground depot when it opened in 2009.^[24] 24 additional Alstom Metropolis & Shanghai Electric C830C trains has started delivery from end July 2014^[25][26] and began operation from 26 June 2015. Currently all 24 C830Cs are in revenue service.

The automated CBTC system on board relies on "continuous two-way digital communication" between each controlled train and the control centre.

Train control

The Circle Line is equipped with Alstom Urbalis 300 Communications-based train control (CBTC) moving block signalling system on the MASTRIA system with Automatic train control (ATC) under Automatic train operation (ATO) GoA 4 (UTO). The subsystems consist of Automatic train protection (ATP) to govern train speed, Iconis Automatic Train Supervision (ATS) to track and schedule trains and Smartlock Computer-based interlocking (CBI) system that prevents incorrect signal and track points to be set.

Train Data Management System (TDMS) which concentrate and dispatch the rolling stock information with fixed equipment. The IAGO Waveguide communications network has the capability to transmit video and is almost maintenance-free. Base stations are located within the signalling equipment room.

Automatic platform screen doors supplied by Westinghouse provide safety for commuters, offering protection from arriving and departing trains.

References

1. "ALSTOM chosen for the world's longest fully automated metro line in Singapore". railway-technology.com. 2002-02-20.
2. "LTA Organises Charity Runway At CCL Open House".
3. hermes. "Four more trains for Circle Line as ridership rises". The Straits Times. Retrieved 2016-03-04.
4. "AsiaOne Transport". Retrieved 21 August 2016.
5. "Circle Line will exceed $6.7b budget" Christopher Tan, The Straits Times, 15 September 2007
6. "News". Retrieved 21 August 2016.
7. Breaking News | The Straits Times
8. http://app.lta.gov.sg/corp_press_content.asp?start=kpt8zx9w8ik53wi33gr59p754348fsj35b9glldouy8ndlh7kb
9. "Train crowding to ease with launch of full Circle Line: Minister Lui". Retrieved 21 August 2016.
10. "Circle Line 6 - Projects - Public Transport - Land Transport Authority". Retrieved 21 August 2016.
11. "Three new stations to close loop on Circle Line". TODAYonline. Retrieved 2016-01-16.
12. "Stop-work order at Telok Blangah site is fourth this year on $6.7b MRT project" T. Rajan, The Straits Times, 22 August 2007
13. "Road above Circle Line construction site caves in" CNA Live, Channel NewsAsia, 24 May 2008
14. "Leaks, damaged cable cause of 4-hour delay on Circle Line". The Straits Times. 29 September 2011. Retrieved 19 October 2011.
15. "Thousands affected by Circle Line disruption". Channel News Asia. 20 September 2011. Retrieved 19 October 2011.
16. "Faulty cable led to Circle Line disruption". Channel News Asia. 20 September 2011. Retrieved 19 October 2011.
17. "Call for thorough probe on Circle Line disruption". Channel News Asia. 22 September 2011. Retrieved 19 October 2011.
18. "Signal interference issue plagues Circle Line again". TODAYonline. Retrieved 2016-12-03.
19. hermesauto (2016-11-02). "Circle Line signal fault that caused train disruptions on Wednesday similar to problem in September: LTA, SMRT". The Straits Times. Retrieved 2016-12-03.
20. "Tech in Asia - Connecting Asia's startup ecosystem". www.techinasia.com. Retrieved 2016-12-03.
21. datagovsg (2016-12-01). "How the Circle Line rogue train was caught with data". Data.gov.sg Blog. Retrieved 2016-12-03.
22. Tuas West Extension Groundbreaking Ceremony Speech (PDF) (Speech). Land Transport Authority. 4 May 2012.
23. AWARD OF ELECTRICAL & MECHANICAL SYSTEMS CONTRACT 830 FOR THE MARINA LINE
24. hermes. "Biggest underground train depot set to become even bigger". The Straits Times. Retrieved 2016-03-04.
25. "LTA and SMRT Award Contracts for New Trains and Re-Signalling Project". Land Transport Authority. 1 February 2012. Archived from the original on 29 September 2013. Retrieved 16 November 2013.
26. "Alstom to supply 34 Metropolis trains and upgrade signaling on the system". 3 February 2012. Retrieved 16 November 2013.

External links

• Media related to Mass Rapid Transit (Singapore) Circle Line at Wikimedia Commons
• Circle Line