The East Coast Depot plan

yuuka
From the Red Line
Published in
8 min readMar 23, 2024

--

Did the LTA bite off more than they can chew?

There has been of course much hand wringing over the delays to TEL5 and DTL3 Extension, which will now open in 2026 — two years after their originally planned opening date of 2024. And I won’t be surprised if that ended up being in the later part of 2026, perhaps even with or after the Circle Line Stage 6.

After all, thanks to the SG MRT Construction Instagram account and related blogs, we can clearly see that progress at Xilin station is far behind what it should be. The LTA blames construction complexity near “critical infrastructure”, but the overall grand scale of the works means that much more than it appears is happening.

After all, three MRT lines are to be integrated into the new depot, and the complicated weave of underground tunnels to connect both the DTL and TEL to this new depot means that practically the whole stretch from the current end of the DTL at Expo, to the end of Sungei Bedok, has to be dug up and rebuilt.

In order to find a satisfactory solution to the overall issue, we must start by asking ourselves, what is TEL5? A new MRT map provides a clue, whereby the same “Under Construction” sticker covers the entire stretch of line from after Bayshore all the way to near Expo. This may be a hint in how the LTA plans to open both stretches of line together.

The weakest link

This approach may also tell us that Sungei Bedok has to be an interchange, both from a technical as well as a policymaking perspective.

It makes sense, as Sungei Bedok station is a single structure with what might be common building services, much like Bayfront before it. But this approach also increases the risk of delays, where if Sungei Bedok’s building services are not ready for operation, both lines cannot run through the station. And as an interchange station surrounded by low density suburbia, opening only one line and making it a dead end may not make a lot of commercial sense.

It’s not in the now, it’s in the later (source: URA SPACE)

As for what the LTA claims to be the main source of the issue, there may be a case to say that delaying Xilin station is acceptable. After all, the potential of the station does not lie in the present, it lies in the future when the land where Changi MRT depot now sits on can be redeveloped. This is why it was clearly stated that any plan submitted to the LTA during the earlier public outreach for the viaduct repurposing, would be for interim, not permanent use. Otherwise, the surroundings are just a few industrial buildings and Laguna Country Club.

Even bus transfers may be untenable in the long run. Bus 35 still serves Tanah Merah Ferry Terminal, the Airport Logistics Park, and Changi East developments. Once Changi East is completed, much of this area will be served by CRL train services, which may reduce the patronage of bus 35 to Xilin station; Aviation Park providing an alternative for Changi North, and any MRT interchange at T5 connecting to the ferry terminal.

As the weakest link, we can see that barely any station structures have risen in the area around Xilin station; a poor sign compared to CCL6, which was always meant to open in 2026 but which has 88% of civil works completed, with many stations’ exits and ancillary buildings already starting to rise.

The LTA can thus consider deferring only Xilin station, by instructing the contractors to prioritise areas needed for trains to run, as well as for the installation of supporting power, control, and tunnel ventilation systems to allow trains to operate, much like the state of Bukit Brown station. Architectural fitting out and passenger facilities can be further delayed, since many in the station service area can continue riding buses or walk to Expo and Tanah Merah stations in the meantime.

This may also allow time to be made up, perhaps allowing DTL trains to connect Expo and Sungei Bedok even perhaps earlier than 2026, without stopping at Xilin station, and close the Eastern Region Line loop as planned. After all, without the eastward connections towards Tampines, there’s less reasons for people to use TEL4.

A compromise

But that is of course assuming the rest of the TEL5+ECID megaproject can open on time.

Even if that’s not possible, it may be worth it to examine whether Bedok South station alone can be opened. It would likely be best to open both TEL5 stations along with eastward service from Sungei Bedok to Expo, but as stated above, the complexity around Sungei Bedok may not make that possible. But if trains can be run through the station out of service, the final TEL5 service pattern can be run with trains emptying at Bedok South, and passing out of service through Sungei Bedok. That makes things much easier for everyone.

If not, things get hairier. It might be possible to use the terminating arrangement for TEL4 at Bayshore, and then extend the service as a single track to Bedok South. It’s not like SMRT is any stranger to this — the single tracking between Labrador Park and HarbourFront stations is being run in a similar way, with a long stretch of single track between the siding at Pasir Panjang, and Labrador Park station. Another siding between one-north and Kent Ridge is being used to enable a more intensive peak hour service.

The same features are seen on TEL4, with a siding between Marine Parade and Marine Terrace stations, located under the civic and community underground space. A simple crossover will be used to turn trains at Bayshore.

That is obviously Marine Parade (source: Samsung C&T)
Planned crossover at Bayshore (photo by me from TEL4 PIC)

It might thus be possible for the TEL to operate a lower amount of service between Marine Terrace and Bedok South, with single tracking in place. Some trains can perhaps terminate at Marine Parade, and perhaps some at Marine Terrace. A lower level of service to Siglap, Bayshore, and Bedok South (perhaps around 6–7 minutes) might be acceptable considering that this is an arrangement that will last two to three years at most, and that during that period, it is not likely that these stations will see very high usage especially with the lack of eastward connections.

Crazy enough to work? (left source: URA SPACE)
Rough track layout from Marine Parade to Bedok South (drawing by me)

The service pattern might just be crazy enough to work.

In comparison, here’s one-north to HarbourFront during the current CCL6 trackworks (drawing by me)

At the very least, what I’d think has to be decoupled from the overall project is the new tracks and platform at Tanah Merah. Completing the new tracks and new platform, even without the depot, can allow for more service on the Changi Airport branch.

Adversity breeds innovation?

We can perhaps learn from Taipei Metro, who experienced the same issues. The Xinzhuang Depot did not open until 2021 — a full eight years after the Xinzhuang Line proper in New Taipei. Like with TEL5, the opening of Danfeng and Huilong stations were also further delayed to mid-2013, supposedly because the tracks in the area were used for train storage. I suspect this was a compromise before the opening of Dongmen station, which provided a track connection from the Xinzhuang Line to the rest of the Taipei Metro network, relieving pressure on the Luzhou Depot. And while the rest of the Xinzhuang Line opened in 2012, Fu Jen University station was pressed into service as a temporary terminal.

This lesson may be directly applicable to open the passenger carrying section of TEL5 without the depot, if the depot is the main concern. Changes will have to be made to train operation and control systems that were designed with the mainline and depot connection to operate together, but now expected to operate independently of each other. Train storage space may also need to be carved out of TEL5 tracks to avoid long deadheading all the way from Mandai Depot in the early mornings and late nights, depending on SMRT’s operating experience with TEL4. Should it be possible to open the DTL3e connection, with or without Xilin station, the same issues may arise on the DTL.

The question now is whether this is possible while upholding standards of safety and reliability we’ve come to demand from the MRT system. Of course, money will have to be spent on change orders for systemwide contractors to make it happen. In Taipei’s case it was worth the money; in order to provide an earlier opening to avoid nearby residents’ anger looking at ghost stations, as well as to avoid compensation claims by contractors from schedule overruns.

Singapore’s sociopolitical systems around land acquisition, government efficiency, and a citizenry that may be resigned to the status quo without the opening of the stations, may mean we can and have avoided many of these issues. Then again, it’s not like they haven’t seen these issues before, as the compensation claims (from the Nicoll Highway collapse) and property acquisition issues already happened with the Circle Line — and don’t forget Buangkok as well. And to mitigate the Alpine bankruptcy, they just worked day and night. They can once again employ these tools, all the more easier at Xilin, where there’s no need to be a good neighbour to residential estates.

There are very real costs of not pushing for earlier micro-staged completions and allowing trouble at just one or two sites to hold back the entire opening. This does not only represent the deprecation costs of hardware that sits unused, or the missed opportunities from passengers not using the line due to a lack of connections. There are also additional costs in providing surge capacity to deal with crowding on other routes that would have been relieved by the timely opening of the MRT line. Not only bus routes, but other train lines, as places like Bedok South are forced to continue relying on bus connections to the existing MRT network.

Perhaps they do recognize it. They could have easily sat on TEL1 and allowed the schedule to drag out to open it together with TEL2; but they did not. Time is of the essence; and perhaps the LTA might do well to innovate in the programme schedule, play catch-up, and then they can throw another party to push forward deadlines. Still, micro-phasing openings can also work when all those tools are exhausted.

At least we can take heart in the fact that this will likely never happen again; while no one can say for sure looking at the complexity of Pasir Ris CRL station, at least there aren’t any 4 in 1 underground depots along the CRL. For now.

Like what you read? Join the Telegram Channel for updates!

--

--

yuuka
From the Red Line

Sometimes I am who I am, but sometimes I am not who I am not.