Up to five stations from Admiralty to Yio Chu Kang MRT stations will be closed for parts of three days during the Vesak Day long weekend to facilitate the construction of a crossover track at the upcoming Canberra station.
Admiralty and Sembawang stations will not operate from May 18 to 20, while Yishun, Khatib and Yio Chu Kang stations will be closed on May 20.
As part of the works, the leftmost lane of Canberra Link, heading in the direction of Sembawang MRT station, will be closed from May 17 at about 10am for the deployment of a crane. It will open again on May 21.
The 72m-long crossover track, which will be built between Sembawang station and the new Canberra station, will allow trains on the North-South Line to cross from one track to the other, thereby increasing the resilience of the line, the Land Transport Authority (LTA) said in a statement yesterday.
"For example, if the northbound track is faulty, affected trains can use the crossover to bypass the faulty stretch by travelling on the southbound track," said the LTA.
The works will be carried out round the clock during the three days and about 110 workers will be involved.
Shuttle buses will be deployed between affected stations.
An express bus service from Woodlands MRT station to the Downtown Line's Bukit Panjang station and vice versa will also operate during the three days.
LTA director of rail expansion Chuah Han Leong said it is not viable to have early closure and late opening of the MRT stations as the works involved have to be done in a continuous process over 72 hours.
On May 18 and 19, trains will turn around at Woodlands and Yishun stations. This will allow workers to remove sections of existing tracks about 40m from the Canberra station platform and to install the new crossover track.
Testing and commissioning of the signalling software for the newly installed track sections will then be carried out on May 20.
The Shuttle 10 bus service will serve the route between affected stations when the works are ongoing. The buses will arrive at the stations every one to three minutes.
Meanwhile, the Express 17 bus service will ferry passengers between Woodlands and Bukit Panjang MRT stations. The buses will arrive every five to eight minutes.
Both bus services will follow the same fare structure as trains.
About 130 buses are expected to be deployed on the first two days of closures, while 170 buses are expected on the third day.
The LTA said it will monitor these shuttle bus services and work with public transport operators to ramp up services if needed. It also advised commuters travelling along affected sectors to plan their journeys in advance and factor in the additional time needed to transfer between shuttle buses and trains.
Seventy-five per cent of construction works at Canberra station have been completed and it is expected to open by the end of this year. The works, which include the crossover track, will cost around $90 million.
With the completion of the new crossover track, there will be more than 50 such tracks on the North-South and East-West lines.
is the East-West Line's Dover station, which opened in 2001.
The LTA said Canberra station is designed with five entrances, which will facilitate better commuter movement and enhance accessibility. The station will also have covered linkways to bus stops and bicycle parks.