The Land Transport Authority (LTA) is making good progress on the multi-year programme to renew the North-South and East-West Lines’ (NSEWL) six core systems. Three of these have been completed: the sleeper replacement, third rail replacement and re-signalling. The remaining three renewal projects will be completed by the early 2020s. These are to: (a) renew the power supply system; (b) replace the track circuits; and (c) replace the NSEWL’s 66 first-generation trains.

Renewing the NSEWL’s Power Supply System

2          The NSEWL’s power supply system renewal works project includes the replacement of 1,300km of power cables, 250km of fibre optic cables, 206 power transformers, 172 switchboards and equipment in 171 substations.

3          This is a massive network-wide undertaking, which requires significant investment of time and resources. Our engineers have been able to leverage the additional engineering hours through the Early Closure and Late Opening of stations to accelerate works. As of December 2019, more than 110km of power cables have been installed, while the 64P touch voltage protection system located within the NSEWL stations have all been replaced with new Voltage Limiting Devices (VLD). The new VLDs are able to help isolate the impact of power faults and prevent these from causing a line-wide disruption to rail operations.

4          About 50 per cent of Direct Current (DC) switchgears have been replaced, with the remaining DC switchgear replacement works expected to be completed by the fourth quarter of 2020. The high voltage system comprising 22kV switchgears, transformers, rectifiers and inverters in nine stations have been replaced, with another 12 stations’ due to be completed by the first half of 2020.

5          Once completed around 2023, the new power supply system will be equipped with enhanced features for real-time condition monitoring. This will enable improved fault detection and prediction capabilities, and allow the rail operator to carry out early intervention works before a fault can develop or worsen.

Track Circuit System Replacement

6          Works to replace the NSEWL’s track circuit system are also in progress. Currently, about a quarter of the works has been completed, with the stretch between the NSL’s Bukit Batok to Khatib stations fully replaced. The new track circuit system will be able to automatically detect broken rails that require repairs, and speed up service recovery efforts following a track circuit fault. The replacement works are expected to be completed around 2022.

Replacement of First-Generation Trains

7          In July 2018, LTA appointed Bombardier to manufacture and deliver 66 new trains to progressively replace the first-generation trains, which have been serving commuters on the NSEWL since 1987.

8          Procurement and manufacturing of the new trains have commenced. The new trains will have built-in condition monitoring and diagnostic systems to detect faults early and track the real-time performance of various train systems. The interiors of the trains have also been designed to make boarding easier and more accessible for all commuters, including parents with strollers and wheelchair users. The trains are on schedule to be delivered progressively from 2021.

9          Even as works on the NSEWL’s remaining three core systems continue, the renewals that have been completed are already contributing to better rail reliability. From October 2018 to September 2019, the NSL’s MKBF increased to 1,434,000 train-km from 894,000 train-km in 2018. In the same period, the EWL’s reliability also rose to 1,045,000 train-km as compared to 408,000 train-km in 2018.