The Grey Line is a planned monorail line in Bangkok, Thailand. The planned initial Phase 1 Grey line route runs along a north - south axis for a distance of 16.25 km. The line would support the growth of residential areas around Pradit Manutham Rd and Kaset-Namawin rd. The route runs from Ram Indra Road, in the northeast of Bangkok, south through Pradit Manuthum Rd along the Chalongrat Expressway going into the downtown district of Thong Lo. It is expected to service 340,000 passengers per day and consist of 15 stations. The Grey line would provide a vital north - south link in the eastern suburbs of Bangkok with other lines including the MRT Pink Line, the proposed MRT Brown Line, MRT Orange Line and BTS Sukhumvit Line.
Phase 2 & 3 extensions
A possible Phase 2 extension would extend from Sukhumvit Rd., along Rama IV Rd., and Ratchadaphisek - Rama 3 Rd and end at The Rama IX Bridge at the Chao Praya river and service the Sathupradit area in Yan Nawa District. The Phase 2 extension would result in a route that is approximately 26 km long. It would also essentially replace much of the Bangkok BRT route. A planned Phase 3 extension from The Rama IX Bridge /Rama 3 rd and would continue along Ratchadapisek rd to link with the BTS Silom Line at Talat Phlu station, the futureMRT Purple Line southern extension and eventually terminate with the MRT Blue Line extension at Tha Phra station. A Phase 3 expansion would result in a total distance for the Grey Line of 39.9 km.
Planning progress
In August 2011, the newly elected Yingluck Shinawatra government decided to defer plans for the Grey Line and the Light Blue Line, citing that the lines are not a priority within their current 10 lines Master plan. The government suggested the Bangkok Metropolitan Administration pursue construction but stated that the BMA would have to fully fund the line itself. The BMA stated in mid 2013 that it considered the Grey monorail line a priority and planned to progress planning by completing an EIA by the end of 2013 for the line to be tendered by early 2014. If approved, construction would take place from 2015 - 2017 for opening in 2018. However, in March 2014, the OTP stated that they would contract a consultant to undertake further study of the Grey Line. In May 2014, a consultant was contracted to undertake a financial feasibility study of the line which is expected to complete its work by the end of 2014. A second public hearing on the proposed line was held in January 2015. An environmental impact assessment was completed in September 2016 but was unsuccessful. More recently in June 2018, the BMA vowed to revive the project by rectifying the EIA and resolve the opposition from locals in the Thong Lor area. The BMA also will seek to gain approval and support from the Expressway Authority of Thailand to construct the line along the Pradit Monutham rd/Chalongrat Expressway corridor. In September 2018, the MRTA Governor stated that the MRTA would like to build the proposed Grey line in order to provide a feeder line to the MRT Pink Line and MRT Brown Line. Also, given that the MRTA is already working with the Expressway Authority of Thailand regarding an integrated design for the MRT Brown line, the MRTA can build on that experience to gain access to land needed for the Grey line, especially at the MRT Brown line interchange at Kaset-Namawin rd. Also under consideration is a Phase 2 and Phase 3 extension along the length of Rama 3 rd, over the Chao Phraya river and along Ratchadapisek rd to Tha Phra to replace the BRT along this route. This would enable the Grey Line to interchange with the BTS Silom Line at Talat Phlu station, the future MRT Purple Line southern extension and link with the MRT Blue Line extension at Tha Phra station. If the Phase 3 extension is built, the total route distance would be 39.9 km. In September 2019 it was announced that the monorail would be built as two disconnected sections and could be ready by 2023.
Stations
The route has a total of 15 planned stations for Phase 1. For Phase 2, 24 stations including the cancelation of Bangkok BRT are planned.