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| name = Downtown MRT Line
Template:Lang | color = 79412A | logo = | logo_width = | image = MRT map DT.svg | image_width = 300px | caption = The Downtown Line is tentatively coloured brown, but change to blue. | type = Rapid transit | system = Mass Rapid Transit (Singapore) | status = Opened (Stage 1), Under Construction (Stage 2, 3) | locale = | start = Bukit Panjang (Stage 2) | end = Expo (Stage 3) | stations = 34 | routes = 1 | ridership = | open = | close = | owner = Land Transport Authority | operator = SBS Transit | character = | stock = Bombardier MOVIA C951 | linelength = Template:Km to mi | tracklength = | notrack = | gauge = Template:RailGauge | el = Third rail | speed = | elevation = | map = Template:MRT route | map_state = collapsed
The Thomson Line will be the sixth Mass Rapid Transit line in Singapore and is currently under planning and evaluation. It will be a fully automatic and driverless system, similar to its three predecessors, and will be completely underground. Announcement of station locations is expected in 2011 or 2012. Completion of the 23-station line (inclusive of 3-reserve stations) is expected in 2018.
The 30 km rail line will be built from Woodlands in the north, through Ang Mo Kio and down the Thomson corridor to the city centre. In total, there will be 23 stations. En-route, the 30-kilometre line will connect from Marina Bay through the Central Business District and up through Ang Mo Kio all the way to Woodlands connecting estates such as Sin Ming, Kebun Baru, Thomson and Kim Seng which do not now have a direct MRT link.
It is one of four more rail systems to be built by 2020. The other three rail systems are the Circle MRT Line, the Downtown MRT Line, and the Eastern Region MRT Line. Together, the four will extend the rail network from the current 138 km of track to 278 km by 2020. When completed, it will improve movement in the city centre, with a train station within every 400m on average, roughly equating a five minute walk. Its network density will rise from 31 km per million residents today to 51 km per million. This will surpass what Hong Kong and Tokyo have today and is comparable to current densities in places like New York and London.
The Thomson Line was first announced on 25 January 2008. Several architectural and engineering consultancy packages have been released in 2010 which indicated an increase in the number of stations from 18 in the initial announcement to 23 and length of the line from 27-km to 30-km.
Preliminary documents show that the Thomson Line rolling stock will differ in specifications from previous lines. Trains are expected to be 4-carriages long (in contrast to previously 6 or 3-carriage long on other lines) and have a standard of 5 doors per side per carriage (in contrast to 4 previously).
The announcement of the new rail line was greeted with much fanfare. However, there have been some concerns about costs and the long wait for the new line Template:Citation needed. On the whole, residents that live near the line have welcomed it.