CR117 - Completion of westbound tunnel

Graphical representation of tunneling progress for contract CR117. Based on compilation of
available information and may not be the most accurate nor up to date.

Contract CR117 has been one of the more elusive contracts to track progress of, mainly due to the different geology at the location which necessitated different construction methods. For instance, the earth retaining & stabilising structure (ERSS) employed at the site uses bore piles instead of diaphragm walls. Similarly, it has been a little difficult to track the progress of tunneling works. Nonetheless, we've managed to probe a bit more and finally have some idea of the progress when it comes to tunneling.

Undated image - A photo of the slurry tunnel boring machine used for the contract.
Source: Skymard / Hnjtx / China Construction Machinery Association

Under this contract, a single slurry tunnel boring machine (TBM) is being used to construct the two tunnels connecting Bright Hill and Teck Ghee stations. The tunnel alignment passes directly underneath Eunoia Junior College (EJC) and is part of the reason development of the campus was delayed - to deconflict the tunnel alignments as the Cross Island Line (CRL)'s route shifted to running along Sin Ming Avenue & Marymount Road as opposed to underneath Ang Mo Kio Avenue 3. This meant that the EJC campus had to leave a no-pile zone to allow the future TBMs of the CRL to pass through unimpeded. This process took time, hence resulted in a delay to the development of EJC's campus. In a photo, the contract CR117 TBM - named Lozen - can be seen sitting along the southern side of the launch shaft, ahead of commencement of tunnel works for the westbound tunnel.

9 January 2026 - A group photo in the contract CR117 launch shaft. The portal for the eastbound
tunnel can be seen under preparation while the westbound tunnel has been completed.
Source: LinkedIn

9 January 2026 - A group photo inside the abandoned shield skin & completed tunnel segments
of the westbound tunnel.
Source: LinkedIn

Subsequent images seen of a site visit show that the westbound tunnel works had progressed significantly, with tunnel rings assembled within the interface zone. Next to this, a portal for the eastbound tunnel could be seen being prepared, with the tunnel seal ring being installed. This is a section of temporary ring that allows the TBM to be guided into the correct position for tunneling works to commence.

An additional group photo during the site visit is taken inside the tunnel. A concrete wall can be seen at the end of the tunnel, along with the TBM shield skin, since stripped of all other internal equipment. This means that the internal components had already been disassembled and brought back to the launch shaft, signaling the completion of tunneling works for the westbound tunnel. Beyond the concrete wall lies the future Teck Ghee station, likely not yet excavated to the platform level to allow for breakthrough & demolition of the wall to allow through passage to the station.

This represents a significant development as yet another tunnel for the project is completed, inching the line forward to completion. There have been more developments, which we will cover in our next posts to update you on tunneling works progress along the CRL.

This post will also be available on Instagram & Facebook on 20 February 2026.