MRTA’s 175-billion-baht rail plan targets two Cabinet submissions in 2028
Four proposed rail lines would add 64.8 kilometres to Greater Bangkok’s network, as the Brown and Silver lines target Cabinet submission in 2028.
- The Mass Rapid Transit Authority of Thailand (MRTA) is preparing four new rail projects valued at 175 billion baht to expand Bangkok's transit network.
- Two of these projects, the Brown Line and the Silver Line, are specifically targeted for submission to the Cabinet for approval in 2028.
- The Brown Line's submission was delayed from 2027 to 2028 due to ongoing negotiations over sharing land with an expressway project.
- The Silver Line is a proposed light rail system designed to connect the Bang Na area with Suvarnabhumi Airport.
The Mass Rapid Transit Authority of Thailand (MRTA) is preparing four new rail projects worth about 175 billion baht to expand connections between Bangkok and surrounding areas, governor Gardphajon Udomdhammabhakdi said. The proposed lines would cover 64.8 kilometres, with the Brown and Silver projects expected to be submitted for Cabinet approval in 2028.
The MRTA’s plans involve coordination over shared land, reviews of projects transferred from the Bangkok Metropolitan Administration (BMA), and design work for a connection to Suvarnabhumi Airport.
Brown Line Cabinet submission shifts to 2028
The MRTA now expects to submit the Brown Line proposal to the Cabinet in 2028, rather than 2027, as discussions continue with the Expressway Authority of Thailand (EXAT) over sharing the right-of-way with an expressway project.
The proposed Brown Line would connect Khae Rai and Lam Sali (Bueng Kum) along a 22.1-kilometre monorail route with 20 stations. Its preliminary investment cost is estimated at 41.7 billion baht.
The Brown Line’s alignment is designed to share land with the east–west expressway project along Ngam Wong Wan and Prasert Manukit roads, with the aim of minimising land-use impacts and traffic disruption. The MRTA and EXAT have yet to reach a conclusion on the shared right-of-way, Gardphajon said.
Grey Line under review after transfer from Bangkok
The MRTA is reviewing the details of Grey Line Phase 1 following the project’s transfer from the BMA. The project has already passed its environmental impact assessment, according to Gardphajon.
The proposed Grey Line monorail would run between Watcharaphon and Thong Lo, covering 16.3 kilometres with 15 stations and an estimated investment cost of around 29 billion baht.
Silver Line studies target Cabinet submission in 2028
The MRTA expects detailed studies for the Silver Line to take approximately one year, with the project targeted for submission to the Cabinet for approval in 2028, Gardphajon said.
The proposed Silver Line would connect Bang Na and Suvarnabhumi Airport using a light rail transit system. The 19.7-kilometre route would have 14 stations and an estimated investment cost of about 89 billion baht.
The Silver Line is divided into two phases:
- Phase 1, Bang Na–Thana City: 14.6 kilometres with 12 stations.
- Phase 2, Thana City–Suvarnabhumi Airport: 5.1 kilometres.
The MRTA is reviewing the Silver Line’s details and design to reflect changes in physical conditions along the proposed route. Discussions are also under way with Airports of Thailand Public Company Limited (AOT) over connecting the line to the passenger terminal on the southern side of Suvarnabhumi Airport.
Silver and Grey lines take priority over Light Blue Line
The MRTA plans to advance the Silver and Grey projects before proceeding with the Light Blue Line, which is classified as a secondary route under the rail network master plan, Gardphajon said.
The proposed Light Blue Line would connect Din Daeng and Sathon over 6.7 kilometres, with nine stations and an estimated investment cost of around 14.7 billion baht. The project would use a light rail transit system.
The MRTA needs to study the Light Blue Line’s details against current conditions following its transfer from the BMA, with its position in the secondary-route programme determining its priority behind the Silver and Grey projects.
