Some 160 staff from train operator SMRT completed maintenance works yesterday that would normally be spread out over a number of nights after service hours.
The full-day closure of 19 stations on the East-West Line and North-South Line gave them time to test the new signalling system and replace track circuits, among other things.
For example, at Jurong East station, workers were spotted replacing a track circuit that spans 150m. It usually takes two to three nights during non-service hours to replace just one.
Overall, the first weekend of planned service disruptions went smoothly although many commuters were caught off guard.
More than 400 SMRT staff were stationed at the affected areas in shifts to direct commuters to shuttle buses that ran parallel to affected MRT stations.
Passengers were charged regular train fares for the shuttle bus rides.
Queues for the shuttle buses stretched for 100m at some points yesterday, but commuters said they still managed to get on a bus within five to 10 minutes.
The decision to institute a series of early closures, later openings and full-day closures at MRT stations over weekends came after a collision between two trains on the East-West Line last month.
Compatibility issues between an old signalling system and a new one caused the collision.
The closures will primarily allow engineers to move the East-West Line to the new signalling system by next June instead of at the end of next year.
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