SINGAPORE - Rail operator SMRT will be introducing flood mitigation measures - already in place at Bishan MRT station to prevent a repeat of October's flooding incident - at four other locations by April.
The four locations - near the Lavender, Redhill, Kembangan and Expo stations on the East-West Line - are at tunnel portals, where above-ground tracks go into underground tunnels.
On Oct 7, flooding in the tunnels between Braddell and Bishan MRT stations, due to a poorly maintained anti-flooding water pump system, shut down a large section of the North-South Line for 14-1/2 hours, affecting 231,000 commuters.
Transport Minister Khaw Boon Wan described the incident as "sad" and "embarrassing".
The new flood mitigation measures include adding more float switches, as well as moving pump control panels - used to manually activate the water pumps - to areas accessible to maintenance staff even when trains are in service, SMRT building and services director Siu Yow Wee told the media on Wednesday (Jan 24).
There were initially five float switches, but there are now eight of them, following the October incident. The switches alert SMRT staff when water levels in pits in the train tunnels rise too high.
As for the pump control panels, staff are normally required to access the track to use the panels at their current location, which could take up to 20 minutes, Mr Siu added. So, relocating the panels makes it faster to access them when needed.
The pump control panels at the four new locations were moved because the train tracks in these areas, which are above street level, do eventually go underground, so there is a risk of flooding.
The panel at Bishan station had been moved earlier; however, this was not the case for the other four locations because they were not as critical as Bishan, Mr Siu said. This is because Bishan is below street level and, as a result, more prone to flooding. But the four new locations are above street level, so any rain water in those areas can drain off to ground level drains, unlike the situation in Bishan.
The additional measures are part of SMRT's overall efforts to enhance the transport operator's flood-mitigation efforts, said Mr Siu.
These include the outsourcing of the maintenance of water pumps to the system manufacturer, water technology provider Xylem.
With the firm taking over preventive maintenance work for the system, this will allow SMRT to take on a supervisory role.
"With the October incident, we found there was a need to enhance our system to make it more robust," said Mr Siu.
He added that measures introduced at Bishan station include installing more float switches as well as two radar sensors, which are able to measure water levels and send SMS alerts to SMRT staff in emergency situations.
Flood-prevention efforts are part of SMRT's overall rail maintenance and upgrading efforts, said Mr Siu, and these include resignalling of the North-South and East-West lines, to ensure commuters experience better journeys.
"We are committed to do this,but we need time," Mr Siu said.