The extension to the mass transit Blue Line that will link Hua Lamphong in Bangkok to Bang Khae on the edge of Thon Buri, on the opposite side of the Chao Phraya River, should open two months ahead of schedule on Aug 12, 2019, officials said Wednesday.
The longer line will run partly underground and partly on an elevated rail track.
"With 99.26% of the civil engineering work already completed, we're likely to see it open sooner than expected," Mass Rapid Transit Authority of Thailand (MRTA) governor Pakapong Sirikantaramas said.
The Blue Line extension will serve as the first subway in Thon Buri, a former capital that now serves as a residential district west of the river. The extension was originally due to open to the public at the end of September next year.
A new fleet of 35 trains will be delivered on a gradual basis from the end of this year, Mr Pakapong said, adding a two-month test run on the 14-kilometre track will start next June.
The newly extended route will comprise 11 stations, including four underground. The route was originally designed to cover 21km from Hua Lamphong to Tao Pun, which lies east of the river, before additional kilometres of track were patched in.
The four subterranean stations are designed to showcase unique cultural landscapes including Chinatown (Yaowarat Road), an old shopping area and an ancient temple. The stations are called Wat Mangkon Kamalawat, Wang Burapha, Sanam Chai and Itsaraphap.
The deadline for the line's second extension is on track, Mr Pakaporn said. The 13km elevated stretch from Tha Phra, which lies west of the river, to Bang Sue in north Bangkok will open in 2020 as scheduled, he said.
In another development, the MRTA plans to better regulate its train drivers by demanding they apply for licences to operate electric trains, Deputy Transport Minister Pailin Chuchottaworn said.
Subway train drivers do not require any official licence at present but this will change when a new rail transport bill is enacted as they will then be compelled to sit exams, he added.
The MRTA is building a training centre to equip drivers with adequate knowledge and skills required by the new law, he said.