Oral Reply by Minister for Transport Khaw Boon Wan to Parliamentary Question on Bukit Panjang LRT Renewal

Miss Cheng Li Hui asked the Minister for Transport 

a.     whether a feasibility study is conducted regarding the options to renew vis-a-vis to rebuild the Bukit Panjang LRT system;

b.     whether causes of past breakdowns will be better resolved and future occurrences prevented as Bombardier has also been involved in the reliability work carried out since 2016; and

c.     whether the renewal process could have commenced before the first half of this year since Bombardier is responsible for the renewal project.

Reply by Minister for Transport Khaw Boon Wan:

1.     LTA has studied all possible options to replace the Bukit Panjang LRT (BPLRT) which is reaching the end of its economic life. These included replacing the LRT system with a non-LRT option, such as running more buses or autonomous vehicles on the existing roads and LRT viaducts. 

2.     After extensive traffic studies, LTA concluded that these alternatives, which would require an extended shutdown of the BPLRT to modify the viaducts, are not feasible. This is because any suspension of the BPLRT during peak hours would require us to deploy 40 double-deck or 80 single-deck buses, at frequencies of as low as three minutes.  The existing roads cannot support such a level of bus deployment. As Bukit Panjang is already built-up, there is limited scope to expand the current road network, and to build additional bus facilities. These options would have created severe traffic delays and unacceptable trade-offs to commuters’ travelling experience. Even if LTA were to implement strict bus priority measures at the expense of motorists, a trip between Choa Chu Kang MRT and Bukit Panjang LRT stations, which are less than three kilometres apart, would take at least 30 minutes by bus due to the heavy road congestion created.  

3.     Hence, LTA discussed the LRT renewal option with several established LRT manufacturers, including the existing supplier, Bombardier of Canada. After a thorough evaluation with SMRT, the LTA Board decided to award the contract to Bombardier in March this year. Bombardier’s proposal was selected because it could be completed sooner, without requiring major civil engineering works or extensive service closures. Bombardier, having worked with LTA and SMRT since 2016 to improve the BPLRT’s reliability, was also deeply familiar with the difficulties the system faced. 

4.     LTA, SMRT and Bombardier have jointly analysed the root causes of past BPLRT breakdowns and delays. They were largely due to faults with the signalling, traction power and train propulsion systems. The renewal will directly address these.

5.     First, the Light Rail Vehicles’ (LRVs’) signal collector shoes tend to lose contact with the signalling system’s signalling rail at tight turns. With the renewal, the functionality of the signalling rail will be replaced by a new wireless Communications-Based Train Control (CBTC) signalling system with better built-in redundancy. 

6.     Second, the traction power system supplies electricity to the LRVs through the power rail. Similar to the signalling system, a recurrent cause of faults is when the LRV’s current collector shoes dislodge from the power rail at sharp turns. The renewal will enhance the power rail with more robust rail brackets and relocate the joints to less severe curves. 

7.     Third, faults with the train propulsion system will be addressed when the first-generation fleet of 19 LRVs are replaced with new models which come with a more reliable Alternating Current (AC) propulsion system. The new fleet will also feature enhanced redundancy and better air-conditioning performance.

8.     Beyond these engineering fixes, LTA will also install more condition monitoring features to support predictive maintenance. 

9.     At the same time, SMRT has contracted Bombardier to provide long-term service support for the renewed BPLRT system. This contract engages Bombardier to provide more expedient technical, logistical and spares support, including training for SMRT’s maintenance staff to build up local expertise.

10.    Design work for the renewal has already commenced. The overhaul, replacement and upgrading of all these critical components and sub-systems will be fully completed by 2024. However, commuters can look forward to smoother and more reliable rides from 2022, when the upgraded trains and signalling system come into operation.

11.    Meanwhile, SMRT has also engaged Bombardier to provide technical support for the existing BPLRT system. LTA, SMRT and Bombardier are committed to improving the reliability of the BPLRT by intensifying preventive and corrective maintenance.  The recently announced Sunday Closures of the BPLRT have been very useful for SMRT’s engineering teams. We thank commuters for their understanding and patience.