Circle Line tunnel works to cause delays from 17 January to 19 April, 2026

SINGAPORE: Passengers on the Circle Line will face delays of up to 30 minutes between 17 January and 19 April, 2026, as major reinforcement works are carried out on a 450m stretch of tunnels.

According to the Land Transport Authority (LTA), the works will strengthen tunnels connecting Mountbatten, Dakota and Paya Lebar stations.

The three-month project will be one of the longest planned MRT service disruptions to date.

LTA said on 1 December, 2025, that the tunnels remain safe, though minor defects such as water leaks have appeared.

The affected tunnels were built in soft marine clay, a material that compresses over time.

This has contributed to “tunnel squatting”, where circular tunnel cross-sections gradually become more elliptical.

LTA said that while previous leaks have been sealed by grouting, long-term deformation could risk future service disruptions if unaddressed.

The authority added that similar geological challenges have been observed in Shanghai, Taipei, Busan, Barcelona and Lisbon.

During the works, trains between Mountbatten, Dakota and Paya Lebar will run on a single platform at 10-minute intervals.

Passengers continuing on the Circle Line will need to change trains at Mountbatten or Paya Lebar.

Train intervals along the wider network will also lengthen.

The HarbourFront–Paya Lebar stretch will see peak-hour intervals increase from two to three minutes.

Services between Mountbatten and the Dhoby Ghaut and Marina Bay stations will run at intervals of about 10 minutes, rather than the usual six.

Across the entire line, commuters should expect slightly longer waits, LTA said.

LTA estimates that about 480,000 passengers will be affected daily.

Interchange stations such as Bishan, Serangoon and Buona Vista are expected to be crowded during peak periods.

The authority cautioned that additional waiting time could extend journeys by up to 30 minutes.

Commuters are encouraged to plan ahead and consider alternative routes where possible.

To ease congestion, several shuttle bus routes will operate during peak hours.

LTA said these will begin on 5 January, 2026, about two weeks before the tunnel closures, to help passengers familiarise themselves with travel alternatives.

A total of 62 shuttle buses will be deployed initially.

LTA noted that demand will be monitored and adjustments made where necessary.

Passengers travelling during peak hours may find it faster to use other MRT lines.

For instance, those coming from the north-east region may transfer to the Circle Line at HarbourFront instead of Serangoon.

The Circle Line comprises 33 stations, of which 30 are in operation.

The remaining Keppel, Cantonment and Prince Edward Road stations are scheduled to open by June 2026.

LTA said the strengthening works are expected to be completed before these remaining stations open.

The installations will involve steel plates to reinforce the tunnel circumference.

The process demands heavy equipment, specialised machinery and multiple work teams.

More than 300 workers and engineers will be deployed around the clock.

Engineering wagons and locomotives equipped with robotic arms and cranes will support the works.

LTA said extended engineering hours are needed due to the scale and complexity of the project.

Dr Goh Kok Hun, LTA’s group director of infrastructure design and engineering, said engineering assessments confirm that the tunnels are safe for rail operations.

He thanked the public for their understanding and said the works will enhance long-term system reliability.

LTA added that tunnel squatting results from ongoing geological processes.

Future works may be required if continued monitoring indicates additional intervention is necessary.

Information on travel arrangements will be available on LTA’s MyTransport.SG app and social media channels, as well as those of SMRT.

Roadshows, posters and station announcements will be deployed ahead of the service adjustments.

Station staff will be on hand to assist passengers, especially seniors and those with mobility challenges.

LTA said it will continue engaging the public to ensure commuters adapt smoothly to the temporary changes.

An earlier round of similar reinforcement works was conducted in 2023 between Promenade and Nicoll Highway.

That two-week effort was required because the area was built on reclaimed land and subject to greater ground pressure.

Singapore to introduce longer MRT closures as ageing rail network requires major upgrades

Acting Transport Minister Jeffrey Siow earlier said in November that longer planned closures will become more common to facilitate major rail upgrades.

He noted that current nightly engineering windows provide only limited working time.

An international panel of rail experts has recommended extended shutdowns for critical renewal works.

LTA said these measures will help ensure safety and operational resilience across the network.