Cross Island Line Construction: CRL1 - A snapshot in April 2026

Overview of CRL1 stations CR4 - CR5 & CR8 - CR11 as at April 2026.
Top (L - R): CR4 - Pasir Ris East, CR5/CP1 - Pasir Ris,
Middle (L - R): CR8 - Hougang, CR9 - Serangoon North
Bottom (L - R): CR10 – Tavistock, CR11 – Ang Mo Kio

Last week, we took a look at the progress of the Cross Island Line (CRL)'s Punggol Extension. This week, we catch up on progress along CRL's phase 1 section, covering 6 contracts under the phase. Join us as we take a look at progress made from Pasir Ris East to Ang Mo Kio in this snapshot update of CRL1.

Phase 1
With ongoing works advancing constantly, most of the stations under the phase 1 contracts have commenced station excavation works, with Serangoon North as an exception. The stations covered in this update employ the use of the top-down method of construction, owing to high developed urban locations requiring construction techniques that minimise movement of soil and surroundings. The top-down method involves concurrent excavation and slab casting activities to be carried out - the top layers are excavated to a sufficient depth before a permanent structural slab is cast with openings to allow progressive excavation to continue.

Summary of construction progress for the stations covered under this update.

On the tunnel boring front, at least 16 out of 29 tunnel drives have since been completed. This represents approximately 55% of tunneling works along this phase of the line. Additional tunnel boring machine (TBM) drive completions can be expected in the coming months, with some machines nearing their final connection points.

We begin our snapshot update at Pasir Ris East and progressively work our way westwards, ending the update at Ang Mo Kio station.

CR4 - Pasir Ris East (Contract CR107)
In a nutshell: With excavation works underway at the main station box, works on the earth retaining & stabilising structures (ERSS) at the station's western end were wrapping up. Demolition was underway for the top-most portions of the diaphragm walls to allow for the construction of the capping beam. Excavation works may likely follow once the capping beam has been completed. Auger machines can be seen on site, likely to allow for the installation of king posts to support upcoming excavation works.

At the main station box, excavation has been going on for some time now. Parts of the station roof slab are visible, having been cast as excavation progresses downwards to the concourse level, and thereafter the platform/base level. Interestingly, a gantry crane has been installed towards the eastern end of the site to facilitate lifting of materials. The presence of a gantry crane for such works is not very common locally.

26 April 2026

CR5 | CP1 - Pasir Ris (Contract CR108)
In a nutshell: At Pasir Ris station, installation of traffic decking over the main station box was still underway. Once installed, the decking would form a platform from which excavated soil could be removed from the station site. Cranes would be able to gain closer access to the construction points for lifting and lowering of materials into and out of the site. Parts of the road near block 537 along Pasir Ris Drive 1 were being prepared for a road diversion, with the lanes being shifted closer to the south.

To the station's west, excavation works were well underway for the western cut & cover tunnels. A crossover will be located here, allowing trains on both the main line and the Punggol extension to switch between bounds as needed. Excavation works here have progressed approximately 2 strut levels down.

At the station's eastern end, a similar site exists for the eastern cut & cover tunnels. This section will see several tunnels being built, with the main line tunnels stacked on top of the Punggol extension tunnels. An additional pair of tunnels will link the two levels, allowing trains to transfer between the two levels and allow trains from the Changi East depot to eventually access the Punggol extension tracks. Excavation works were underway here, with tubular struts being used to hold the ERSS walls apart.

Finally, tunneling works for the westbound tunnel were nearing the completion of the first drive for TBM Terra. The TBM was currently sited near the pedestrian overhead bridge next to block 104 and Pasir Ris East Community Club. It is likely that the drive would be completed within the next 1 to 2 months' time, after which the TBM would be reassembled at the launch shaft for the second drive to construct the eastbound tunnel.

26 April 2026

CR8 - Hougang (Contract CR112)
In a nutshell: Over at Hougang station, the section of the site used to support tunneling works was deing decommissioned. The layer of cement used to ensure stable and flat ground was being demolished ahead of handover of the site back to the state for the construction of the subsequent integrated development. With tunneling works since completed, disassembly of the acoustic shed at the launch shaft was also nearly completed.

Elsewhere within the main station box site, excavation works continued as progressive slab casting took place concurrently. Owing to the depth of the station, it was not possible to determine how deep excavation works had progressed. Works at the paid transfer connection abutting the existing North East Line (NEL) station, however, were still visible with the level of the roof slab likely being reached.

Excavation works for the subway linking to Exit 6 were also underway, with the trench becoming more visible. Similar works were beginning for Exit 5 along Hougang Avenue 10. Within the existing NEL station, works to expand the existing concourse level were taking shape. Steel sections were assembled to provide additional structural strength before rebar was added on. Casting of the expanded slab had yet to commence.

26 April 2026

CR9 - Serangoon North (Contract CR113)
In a nutshell: Excavation works appear to not have commenced at the station site yet, with works still centred on the completion of the diaphragm walls along the station's southern edge.

18 April 2026

CR10 - Tavistock (Contract CR115)
In a nutshell: With ERSS construction works completed, progress at the main station box was largely unremarkable. Heavy equipment was scatted along the site, with no major excavation works seen as yet.

TBM3 is currently boring the eastbound tunnels towards Serangoon North station. Its location at the surface was demarcated by the presence of a watchman station, indicated by a multi-coloured umbrella. The TBM was located near the end of the drive, in the vicinity of the pedestrian overhead bridge between blocks 101 and 554.

TBM1B, on the other hand, still appeared to have some distance to cover with its watchman station being spotted in the vicinity of the pedestrian overhead bridge between block 565 and the Teck Ghee Parkview precinct. It may be likely that the TBM had stopped here momentarily to transition from the initial drive into the main drive.

18 April 2026

CR11 - Ang Mo Kio (Contract CR116)
In a nutshell: Excavation works were underway at the final station covered in this update at Ang Mo Kio. These works were taking place both within the main station box as well as the cut & cover tunnel section to the east of the station box. Apart from the excavation works ongoing, the station site also implemented several road diversions to allow phased works to proceed.