Longer journey times at 7 Circle Line stations in June, July for tunnel strengthening maintenance
Maintenance work will be carried out on a tunnel segment that had been found to be "subject to greater pressure", said LTA.
SINGAPORE: Train services at seven stations along the Circle Line (CCL) will be adjusted in June and July because of extra maintenance work, the Land Transport Authority (LTA) said on Wednesday (May 24).
Routine inspections by LTA and public transport operators found that a "small segment" of the tunnel between Promenade and Nicoll Highway stations had been "subject to greater pressure", said LTA.
The affected stations are Dhoby Ghaut, Bras Basah, Esplanade, Promenade, Nicoll Highway, Marina Bay and Bayfront. The services will be adjusted over a six-week period.
From Jun 11 to Jul 20, services at the seven stations will only operate from one platform after 9pm, except from Jun 16 to Jun 18, Jun 28 to Jun 29, Jul 1 to Jul 2, Jul 7 to Jul 8, and Jul 14 to Jul 16.
“This will result in longer headways, and commuters will experience additional travel times of up to 30 minutes,” said LTA.
During the single platform service period, shuttle train services will be available between Dhoby Ghaut and Promenade (Shuttle Service A) at 15-minute intervals, and between Marina Bay to Stadium (Shuttle Service B) at 20-minute intervals.
In response to CNA's queries, an LTA spokesperson said the pressure issue was picked up during its tunnel monitoring and inspection regime.
LTA assessed that the affected tunnel segment posed no safety risks to CCL train operations.
“Nonetheless, LTA will carry out precautionary maintenance and strengthening works including installation of steel supports to the tunnel rings to ensure the long-term integrity of the tunnel,” said LTA.
“LTA and the operators will continue to regularly monitor tunnels used for rail operations as part of our maintenance regime.”
What LTA is doing to strengthen this segment of the CCL line
An LTA spokesperson said on Wednesday that monitoring instruments have been set up in this segment of the CCL tunnel to measure the tunnel movement levels around the clock, ensuring that they are within safe levels.
The extra maintenance work to rectify the "higher than projected" ground pressure will include the installation of extra steel plates as an "additional strengthening measure".
As certain tunnel stretches are located in reclaimed land consisting of marine clay, some settlement can still be expected for some time after construction and as such, these stretches are monitored even more closely by LTA.
The spokesperson added the pressure issue had only been detected at this particular CCL tunnel stretch.
All underground tunnels are inspected regularly by a team of engineering, track and infrastructural professionals, and LTA has a regular monitoring and inspection regime in place for all rail tunnels.
It advised commuters to plan their journeys ahead of time and use other rail lines or bus services to minimise inconvenience.
They may refer to LTA’s MyTransport.SG mobile application and LTA’s and SMRT’s social media pages for more details.Â
Posters and station announcements will also be rolled out at all CCL stations and selected stations on alternate MRT lines that interchange with its stations, said LTA.
Station staff will also be deployed at the affected stations.