I assure Dr V. Subramaniam that SMRT is committed to fixing issues he has raised ("SMRT must fix systemic, structural issues"; yesterday).

Our recently published Your Journey Matters contains useful information on our ongoing efforts to renew and improve the North-South and East-West Lines (NSEWL). It can be found on our website: http://www.smrt.com.sg/Portals/0/PDFs/Your%20Journey%20Matters.pdf

In particular, it points to the sleeper replacement, resignalling and third-rail replacement projects, and to the upgrading of older trains and the delivery of new trains to increase passenger capacity.

SMRT is making good progress in these multi-year, multi-project efforts to renew the NSEWL. These efforts include power substation upgrading and renewal works.

The disruption last Wednesday was caused by a damaged power breaker at the Ang Mo Kio MRT substation.

There are 72 substations that serve the NSEWL. We began upgrading and renewal works in the middle of this year and these will be completed by 2019.

Such upgrading and renewal works need to be carefully managed so as to ensure that power continues to support the live network where train services operate.

This effort will incorporate improved design and safety features. It will also involve the upgrading of power capacity to cope with a larger train fleet operating at shorter intervals.

While we push ahead with upgrading and renewal works, we are also strengthening our maintenance systems and processes, especially with the setting up of a new maintenance operations centre in August.

To support all these efforts, we have substantially reinforced our engineering workforce.

Dr Subramaniam noted the efficient recovery process in the aftermath of last Wednesday's train disruption. SMRT has been working hard with the Land Transport Authority to improve our service recovery measures.

We are also constantly improving customer service touch points in our network to better serve our passengers.

I assure Dr Subramaniam that we are strengthening management controls and regular audits of the train network. The system has been reviewed in its entirety, leading to the extensive range of measures described here.

SMRT is a responsible public transport operator and we are accountable to all our commuters.

But we do need some time to implement these programmes.

I am confident that when the NSEWL is successfully renewed and the range of enhanced maintenance measures is fully implemented, commuters can look forward to a rail network with far better reliability.

Lee Ling Wee

Managing Director

SMRT Trains