Yellow Line (Bangkok)

The MRT Yellow Line is an elevated mass rapid transit line currently under construction in Bangkok and Samut Prakan Province, Thailand. The 30.4-kilometre-long (18.9 mi) line will have 23 stations and cost 55 billion baht. The line was originally proposed in 2005 by the Office of Transport and Traffic Policy and Planning to be an heavy rail underground line along Lat Phrao rd and then elevated from Lam Sali junction to Samrong. However, it was decided in 2012 to build an elevated monorail line for the whole length in order to reduce construction costs.

MRT Yellow Line สายสีเหลือง
Overview
Type	Monorail
System	Metropolitan Rapid Transit
Status	Under Construction
Locale	Bangkok and Samut Prakan, Thailand
Termini	Lat Phrao Samrong
Stations	23
Operation
Planned opening	June 2022
Owner	Mass Rapid Transit Authority of Thailand
Operator(s)	Eastern Bangkok Monorail Company Limited
Character	Elevated
Rolling stock	Bombardier INNOVIA Monorail 300 4 cars per set
Technical
Line length	30.4 kilometers (18.9 mi) (est.)
Number of tracks	2 monorail tracks
Electrification	750 V DC
Operating speed	80 km/h (50 mph)
Route map Ratchada Lat Phrao  MRT  Phawana Chok Chai 4 Lat Phrao 71 Lat Phrao 83 Mahatthai Lat Phrao 101 Bang Kapi Yaek Lam Sali Lam Sali  MRT  Si Kritha Phatthanakan Hua Mak  ARL   SRT  Khlong Kalantan Si Nut Srinagarindra 38 Suan Luang Ro 9 (King Rama IX Park) Si Udom Si Iam Si La Salle Si Bearing Si Dan Si Thepha Thipphawan Samrong  BTS

The MRT Yellow Line will provide mass transit along the heavily congested Lat Phrao road and Srinagarindra road corridors. The line will link 6 other lines; the MRT Blue Line, interchange with the MRT Orange Line (which is under construction), the planned MRT Grey Line and MRT Brown Lines, the Airport Rail Link (Bangkok) and finally the BTS Sukhumvit Line. As such, it will be an important cross city link in the middle north-eastern and eastern areas of Bangkok.

Preliminary site works began in late 2017 with major construction work starting from March 2018. At the end of July 2020, construction had progressed to 62.44%[1]

The line is planned to open in June 2022.

Alignment

The line starts at the intersection of Ratachadapisek and Lat Phrao roads where it interchanges with the MRT Blue Line at Lat Phrao station. The line then heads east along Lat Phrao road to Bangkapi junction where it will interchange with the MRT Orange Line Lam Sali station, before heading south along Srinagarindra Road to Hua Mark where it will interchange with the Airport Rail Link Hua Mak station.

From Hua Mark, the route continues south along Srinagarindra Road past Bangna-Trat Road all the way to Thepha Rak Road in Samut Prakan Province, then heading west along Thepha Rak Road before terminating at Samrong of the BTS Sukhumvit Line.[2]

The line will be built from Ratchada (Y1) to Samrong (Y23), with construction planned to take four years to complete. The Yellow Line depot will be located at Debaratana Road adjacent to Si Iam station. [3]

History

The MRT Yellow line was first proposed by the Office of Transport and Traffic Policy and Planning (OTP) in 2004 as a heavy rail underground and elevated metro line as part of the 10 line metro plan which was taken to the February 2005 election. In 2009, it was suggested to change the line to an elevated monorail line as a cost saving measure. In December 2011, the MRTA was instructed by the MOT to divide the MRT Yellow Line into two phases for tender and construction purposes and to reduce land appropriation costs.[4] In June 2012, the MRTA contracted consultants to undertake detailed designs of the line. In February 2013, OTP stated that the tender for the MRT Yellow Line should be ready by late 2013 for tender in early 2014.[5] By August 2013, this timeline had changed to a mid-2014 tender date.[6]

However, similar to the MRT Pink Line, delays in finalising the technical requirements of the tender in relation to the selection of monorail rolling stock which determines the type of track to be constructed resulted in further delays. The subsequent political turmoil of late 2013 and early 2014 caused even more delay. Thereafter, the coup of May 2014 resulted in a new military administration and the tender being deferred for 2014. The MRTA tender was subsequently not released until mid-2016. In early December 2016, BSR Joint Venture (comprising BTS Group Holdings which owns 75%, Sino-Thai Engineering and Construction - STEC, and Ratchaburi Electricity Generation Holding - RATCH), won the bid for the line. The BSR also won the bid for the MRT Pink Line. [7]

On June 16 2017, a contract was signed for the line with the Mass Rapid Transit Authority of Thailand and a consortium including BTS Group Holdings, Sino-Thai Engineering and Construction, and Ratchaburi Electricity Generation Holding. BSR has established the Eastern Bangkok Monorail Company Limited to operate the monorail. A proposed 2 station extension of the route north from the current Ratchada terminus to link to the BTS Sukhumvit Line Extension at Ratchayothin station has also been proposed by the BSR Joint Venture.[8] However, this extension is opposed by the MRT Blue Line operator BEM due to concerns regarding loss of revenue. [9]

Construction Progress

Construction of the MRT Yellow Line began in March 2018 with the BSR consortium establishing a number of preparation work sites along the Lat Phrao rd with the closure of lanes along this traffic dense east-west corridor. By August 2018, construction had expanded to along the Srinakarin rd section which is also where the depot will be built [10] By 30 September 2018, overall construction had progressed to 9.61% [11] At the end of March 2019, construction has progressed to 30.40%[12] By the end of July 2019, civil construction had further advanced to 39.92% [13] At the end of October 2019, construction had progressed to 45.88%[14] By the end of January 2020, construction had progressed to 51.81%[15] By the end of May 2020, construction had progressed to 59.42%[16]

At the end of July 2020, construction had progressed to 62.44%[17]

Rolling stock

BSR selected Bombardier INNOVIA Monorail 300 rolling stock for the MRT Yellow line.[18] The BSR has announced that they will purchase 28, 4 car sets to operate the MRT Yellow line.[19]

Innovia Monorail 300, Line 15 (Silver), São Paulo Metro, Brazil

Technical Characteristics

• Low profile vehicles/low floor height above beam[20]
• Distinct sloped nose/end-cap
• Inter-car walkthrough[20]
• Rubber-tires and permanent magnet motor[20]
• Aluminium body, steel underframe, composite end cap
• Innovia Monorails are all fully automated and are equipped with CITYFLO 650 communications-based train control for driverless operation to increase reliability, shorten head ways between trains and lower maintenance costs. .[21]

Guidebeams

The Bombardier INNOVIA Monorail 300 operates on a narrow, elevated guidebeam. Pre-cast, post-tensioned guidebeams are constructed at an off-site location and later installed on the system. The guidebeams are 690 mm (27 in) wide.[20] The Innovia Monorail 300 was designed to navigate curves as tight as 46 m and a maximum grade of 6%. Monorail switches are either beam replacement or multi-position pivot switches.[22] The system will have evacuation walkways down the entire length of the guidebeam. These walkways allow passengers to escape any onboard hazard. The maintenance crew also uses these walkways for repairs and general maintenance to the system.[23]

List of planned stations

The 30.4 km Yellow Line will have 23 stations (with a proposed extension of two stations):[24]

Code	Station Name	Transfers	Opening	Province
YLEX-02	Phaholyothin 24 (proposed extension)	BTS  Phahon Yothin 24	2022	Bangkok
YLEX-01	Chankasem (proposed extension)
Y1	Lat Phrao	MRT  Lat Phrao
Y2	Phawana
Y3	Chok Chai 4
Y4	Lat Phrao 71
Y5	Lat Phrao 83	MRL  Chalong Rat (planned)
Y6	Mahatthai
Y7	Lat Phrao 101
Y8	Bang Kapi
Y9	Yaek Lam Sali	MRT  Yaek Lam Sali (under construction)  MRT  Chalong Rat (design phase)
Y10	Si Kritha
Y11	Patthanakan	SRT  Hua Mak (planned)  ARL  Hua Mak
Y12	Khlong Kalantan
Y13	Si Nut
Y14	Srinagarindra 38
Y15	Suan Luang Ro 9 (King Rama IX Park)
Y16	Si Udom
Y17	Si Iam	BTS  Wat Si Iam (proposed)
Y18	Si La Salle
Y19	Si Bearing			Samut Prakan
Y20	Si Dan
Y21	Si Thepha
Y22	Thipphawan
Y23	Samrong	BTS  Samrong

Potential future extension

A proposed 2 station extension of the route north from the current Ratchada terminus to link to the BTS Sukhumvit Line Extension at Ratchayothin station has also been proposed by the BSR Joint Venture.[25] However, this extension is opposed by the MRT Blue Line operator BEM. [26]

When completed the Yellow Line will terminate at Samrong. A future extension from Samrong across the Chao Phraya River to link with the MRT Purple Line at Rat Burana has been canvassed by the OTP.

See also

• Mass Rapid Transit Master Plan in Bangkok Metropolitan Region

References

1. https://www.facebook.com/MRTA.PR/photos/pcb.2574152359468149/2574151689468216 MRTA Press, 5 August 2020
2. MRTA route of the Yellow Line (In Thai) Archived 2013-11-21 at the Wayback Machine
3. "2Bangkok Yellow Line thread" Semi-regular updates, articles, pictures and commentary (In English)
4. "ฐานเศรษฐกิจ - Connecting Opportunity". Retrieved 27 August 2016.
5. "Archived copy". Archived from the original on 2013-12-16. Retrieved 2014-06-27.CS1 maint: archived copy as title (link)
6. http://www.manager.co.th/iBizChannel/ViewNews.aspx?NewsID=9560000105880
7. "BSR Joint venture wins rights for Bangkok's Yellow, Pink line MRTA construction". Bangkok Post. 7 December 2016.
8. "Junta to call bids for most infra projects - The Nation". The Nation. Retrieved 2017-06-17.
9. Author meeting with MRTA planning division on 7 August 2019 at MTRA Headquarters
10. "Construction of monorail lines gets ceremonial launch". Bangkok Post. 27 August 2018.
11. https://www.mrta.co.th/th/news/information/. MRTA Press, 12 October 2018
12. https://www.facebook.com/MRTA.PR/photos/a.1433440196872710/2214355752114480 MRTA Press, 12 April 2019
13. https://www.facebook.com/MRTA.PR/photos/a.1433440196872710/2293373100879411 MRTA Press, 16 August 2019
14. https://www.mrta.co.th/th/news/information/MRTA Press, 10 November 2019
15. https://www.facebook.com/MRTA.PR/photos/a.1409211292628934/2436659376550782 MRTA Press, 7 February 2020
16. https://www.facebook.com/MRTA.PR/posts/2526580167558702 MRTA Press, 4 June 2020
17. https://www.facebook.com/MRTA.PR/photos/pcb.2574152359468149/2574151689468216 MRTA Press, 5 August 2020
18. https://www.prachachat.net/news_detail.php?newsid=1497601230
19. http://www.manager.co.th/iBizChannel/ViewNews.aspx?NewsID=9600000055953
20. "ALWEG - Bombardier Innovia Monorail 300". The Monorail Society - Technical Page. The Monorail Society. Archived from the original on 2015-07-07.
21. "Bombardier named systems supplier of the year - INNOVIA Monorail 300 system and CITYFLO 650 technology are winners in Sao Paulo". Purchasing B2B. Purchasing B2B. Archived from the original on 2015-07-13. Retrieved 2015-07-06.
22. "INNOVIA Monorail 300 System: a mass transport solution for the megacity of São Paulo" (PDF). CG/LA Infrastructure, Inc. CG/LA Infrastructure, Inc.
23. "URBAN MONORAIL TRACK". Monorail Australia. The Monorail Society.
24. "รายงานการเปลี่ยนแปลงรายละเอียดโครงการ ในรายงานการวิเคราะห์ผลกระทบสิ่งแวดล้อม (รายงานฉบับสมบูรณ์) โครงการรถไฟฟ้า สายสีเหลือง ช่วงลาดพร้าว - สำโรง" (PDF) (in Thai).
25. "Junta to call bids for most infra projects - The Nation". The Nation. Retrieved 2017-06-17.
26. Author meeting with MRTA planning division on 7 August 2019 at MTRA Headquarters

External links

• Official website

• Airport Rail Link, BTS, MRT & BRT network map