North-East MRT Line breakdown - 15 Mar 2012

LTA to probe breakdown on N-E Line
Pair of snapped cables blamed for 10-hour disruption of services

By Christopher Tan, The Straits Times, 16 Mar 2012

A PAIR of broken stainless steel cables - each no thicker than 1cm - caused a 10-hour disruption along the North-East MRT Line yesterday that affected about 90,000 commuters.

The breakdown comes just three months after two massive disruptions on the North-South Line, and is likely to fuel more questions about the reliability of the rail system.

A Ministry of Transport spokesman told The Straits Times that yesterday's incident was unrelated to the two disruptions in December.

A Committee of Inquiry (COI) was set up to get to the bottom of the December incidents, and the spokesman said the COI - slated to begin hearings next month - will continue to focus on the December incidents.

But, he added, the Land Transport Authority (LTA) and North-East Line operator SBS Transit are investigating yesterday's disruption.

The LTA, which held a press conference together with SBS Transit, said it would conduct a probe immediately and provide a full report to the ministry.

The cables which snapped on the nine-year-old North-East Line were part of a counterweight system that kept overhead power lines which supplied electricity to the trains taut and aligned.

At 5am yesterday, before service for the day began, SBS Transit discovered that a pair of these cables 1km south of Outram station had snapped, causing power lines at that stretch to sag.

Repair work began almost at once but SBS Transit could not start services on five stations from Dhoby Ghaut to HarbourFront until much later.

SBS Transit chief executive Gan Juat Kiat said at a press conference that no one knows what caused the cables to snap. He said they were last inspected during a regular three-month maintenance programme on Feb 20.

Had trains been running when the cables snapped, they would have stalled after Outram, leaving thousands of passengers stranded inside the tunnel.

Works to replace the cables were expected to be completed by 11.30am, but took until 2pm. Then, SBS Transit discovered there was an electrical insulation flaw along the line.

It eventually traced it to a point near the Outram station. By the time this was fixed, more than 10 hours had lapsed.

Service resumed at 4.35pm, just before thousands of commuters began heading home in the evening rush hour, but well after thousands were inconvenienced in the first half of the day.

Operations manager Arun Prasath, 30, was one of them. He boarded the train at Buangkok and said commuters were kept waiting at Potong Pasir station for a long time. 'I found out the situation when I got to Dhoby Ghaut. I alighted and took the shuttle to Little India and walked to the office.'

Transport Minister Lui Tuck Yew was soon at the scene. Speaking to reporters outside Dhoby Ghaut interchange at about 9.20am, Mr Lui, who was supposed to be on leave, said the response to the breakdown was better managed than in the previous incidents. There was better dissemination of information and 'shuttle buses were arriving very frequently'.

SBS Transit deployed 74 free shuttle buses and ran them at three-minute intervals. On top of this, affected commuters could hop on to regular bus services that plied the route for free - but not many did.

Mr Lui said it could be because this was the first time these services were free. 'I think it will take some time for people to get used to the idea that all the services are free, and they can really find many other alternatives to get to their destination.'

As part of investigations, the broken cables will be sent for a laboratory test, SBS Transit's Mr Gan said.

In 2007, a North-East Line breakdown affected some 100,000 commuters. It was traced to faulty insulators - also found near Outram station - but from a different supplier.

Mr Gan added that SBS Transit would conduct a thorough check on all 40 pairs of such cables along the entire 20km line before the start of service today.

Why the trains could not be run
Broken cables caused wires to sag, disrupting power supply to trains
By Goh Chin Lian, The Straits Times, 16 Mar 2012

SOME time before 5am yesterday, a series of events occurred in the tunnel between Outram Park and HarbourFront stations of the North-East Line.

Steel cables broke, concrete weights fell and two overhead wires supplying power to the trains sagged, one to the ground and the other in mid-air.

Once the cables break, and the overhead wires sag, no train can pass through as there is no power supply.

Luckily, at about 5am, before service started, someone noticed something amiss. Maintenance crew discovered two broken cables. They form part of a system of weights that hold the overhead wires taut. Each cable, under 1cm thick, holds a concrete weight of at least three-quarters of a tonne.

Engineers studying the cables later would puzzle over why they snapped. For one thing, the cables are designed to hold much more than 10 times the weight they carry. No corrosion was found on them and no faults were reported when they were last checked about a month ago.

One theory is that one cable broke first, and its weight fell onto metal supports fixed along the wall, leading to one overhead wire starting to sag. This could have added pressure on the second wire, resulting in the second cable snapping.

The workers wasted no time launching repairs. But as the clock ticked away and daybreak came, they realised much more work had to be done to replace the cables and put the overhead wires up again.

As emergency operations swung into play above ground, a team of 30 workmen and engineers donning reflective vests laboured underneath.

They erected scaffolding so they could climb up to the wires and misaligned wire supports. Others worked on replacing the cables.

At one point, it looked like they could complete the work before the lunch hour and the trains could run at 11.30am. But repairs were completed only at 1pm.

Checks followed on the alignment of the wires and supports, and almost everyone was hopeful that the train service could be restored around 2pm.

As a matter of course, electrical wires in the tunnel were checked for their resistance level before the green light could be given to turn on the power.

But instrument readings revealed another problem: low resistance, suggesting a leak somewhere in electrical insulation.

At 3pm, workers traced the fault to a section near the spot where the cables had broken, and repaired it. Engineers ordered an empty train to be sent through the tunnel to make sure all was fine. At 4.35pm, train doors opened to receive the commuters.

But more work remains. In the wee hours of this morning, scores of workers were to have fanned out along the rest of the 20km North-East Line where 40 pairs of the cables are found.

Yesterday's disruption was different from the ones in December on the North South Line, where brackets securing a rail on the ground that supplies power to the trains were found dislodged.

While North-East Line trains are powered by overhead wires, trains on the North South, East West and Circle Lines receive power from a rail on the ground.




 

Thumbs up for free shuttle bus services

But some say they could have been told regular buses were also free
By Royston Sim, The Straits Times, 16 Mar 2012

COMMUTERS affected by the breakdown on the MRT's North-East Line welcomed the shuttle buses deployed to help them.

But some said more could have been done to alert them that they could also hop onto any regular service outside the stations and have a ride for free.

That was the general view of commuters affected by the more than 10-hour disruption of services at five stations on the line yesterday.

Unlike the two major disruptions on the North-South Line in December when shuttle buses were slow to arrive and fraught with issues, commuters yesterday found the free shuttle bus services largely improved.

North-East Line operator SBS Transit appeared to have taken in lessons from the flak which rival operator SMRT got last year.

The fault was detected at about 5am and 59 free shuttle buses and 63 'goodwill ambassadors' were sent to the five stations - Dhoby Ghaut, Clarke Quay, Chinatown, Outram and HarbourFront, the last stop on the line.

More buses were later added, and all in, SBS Transit deployed 74 buses to ferry commuters between Dhoby Ghaut and HarbourFront. Buses arrived at pick-up points every three minutes or so.

Commuters said the crush at the Dhoby Ghaut interchange station was at its worst just after 8am.

They were told that the service between Dhoby Ghaut and HarbourFront was down because of a 'power system failure', and that they could get to those stations via free shuttle buses.

At Dhoby Ghaut, a sign was placed at a station exit on the North-South Line side and station staff directed commuters to the pick-up point.

A clerk, who wanted to be known only as Mr Tan, 55, said he boarded the North-East Line train at 8am from Punggol to get to work at HarbourFront.

There were signboards at Punggol warning about the train disruption. At Dhoby Ghaut, he was told by MRT staff to take the Circle Line to HarbourFront.

A few minutes after he boarded the Circle Line train, he realised that the trip to HarbourFront would take him an hour. He returned to Dhoby Ghaut station to take the free shuttle bus instead.

By then he was fuming, and wondered why free shuttle services could not have been run from other NEL stations like Little India or Farrer Park to ease the human and bus congestion at Dhoby Ghaut.

A long column snaking back into Plaza Singapura formed as the number of office-bound commuters waiting to board the bridging services grew steadily.

On the road, a queue of SBS shuttle buses waiting to ferry passengers had also formed, slowing down the flow of regular bus services and leading to traffic snarls along Orchard Road.

Police officers and other staff later divided the crowd into three separate lines. They also put up barriers after 9am to better organise commuters.

Public relations executive Lee Kiat Chin had no problems with the transfer from train to bus at Dhoby Ghaut. 'I guess with the previous breakdowns, they are now experienced in getting the people to the alternative means to get to where they are going,' she said.

Even so, she found herself 40 minutes late for work, as the bus took longer than the usual five minutes to get from Dhoby Ghaut to Outram by train.

While feedback on the bridging services was generally positive, an arrangement last month to provide free bus services at affected stations as an alternative to bridging buses went largely unnoticed.

Under this measure, passengers can board any SMRT or SBS Transit bus in the area for free, instead of waiting for complimentary shuttle buses to arrive.

Transport Minister Lui Tuck Yew, who arrived at Dhoby Ghaut around 9.15am to observe the situation, noted that commuters opted for the free shuttle buses, shunning regular services even though these could also take them to the other NEL stations.

Commuters who boarded normal bus services from affected stations were still tapping their ez-link cards as well, unaware that they could ride for free. Bus drivers did not stop them either.

After 11am, an SBS Transit staff member was deployed to the bus stop opposite VivoCity to remind drivers and passengers that bus rides were free.

When asked, the staff member said: 'We didn't have enough people to deploy and remind the bus drivers and had to wait for more people to come... Hopefully it's not too late now.'

Mr Lui said this was one area that needed improvement. If the shuttle buses had to be dispersed over a longer stretch of stations in the future, reliance on normal services would be even more critical, he said.

'It is very important that we go back and work through how we can encourage more people to take the normal services rather than just to rely solely on the shuttles.'

The disruption left many late for their appointments.

Madam S.E. Teo, 66, was on her way from Hougang to Singapore General Hospital for a piles operation.

Looking flustered, she said: 'I'm really in a big rush. I don't think I can make it in time.'

Still, many commuters, such as retiree Michael Tan, felt the situation was far more orderly and organised this time, compared to December. Mr Tan, who is in his 50s, said staff gave clear instructions and he knew how to get from HarbourFront to Outram.

Some people, such as retiree Koh Wee Chye, 59, took advantage of the free shuttle buses. He boarded a bus at Chinatown and went to Dhoby Ghaut to 'see what was happening'. He said: 'The bus is free, and I have lots of time.'

Response to breakdown better, but scope to do more
By Jermyn Chow, Cherie Thio, Tham Yuen-C & Royston Sim, The Straits Times, 16 Mar 2012

COMMUTERS said yesterday's MRT disruption was generally better handled than the breakdowns in December last year.

What was done better this time

Free shuttle buses at frequent intervals: They arrived every three to five minutes and cleared the crowds quickly from the affected stations. In some places after the morning peak hour, shuttle buses were waiting for commuters.

Health products seller Dennis Ong, 43, who was caught in the MRT breakdown on Dec 15 last year, rated yesterday's breakdown as far less serious and said it was better managed.

'With experience from the first time, it should be better. SBS Transit knew about this early and could prepare,' he said. 'But our train service is terrible. It must be improved.'


Better human-traffic management: SBS Transit employees in neon-coloured vests were at almost every entrance or exit of the affected stations to direct commuters to pick-up points for the free shuttle buses, and to advise them on alternative transport routes.

One of these 'goodwill ambassadors' said he received a text message at 6.15am assigning him for duty at HarbourFront station. He and his colleagues knew what to do as they had gone through drills for a mock emergency last month.

Accounts executive Priscilla Ng, 39, who was headed to Orchard Road from HarbourFront station, said: 'It's good that every few steps I took, there was someone to give me clear instructions.'

More frequent announcements: Announcements were made in English and Mandarin every two to three minutes along the North-East Line to spread the word about the disruption, and to inform commuters about bus bridging services. Announcements were also made in both languages on the other MRT lines.

Even so, some commuters on the unaffected lines said they found out only via text message and suggested that the frequency of announcements on those lines could be increased in future.

Clearer and more visible signs: More signs were put up in stations and at gantries to inform commuters about the disruption and where to go for the bus rides. Housewife Irene Ong, 64, who boarded the bus at Chinatown station, said: 'We heard the news at home, so we came straight to the bus stop. I think the signs were pretty clear. We didn't get lost.'

SBS Transit and SMRT staff in sync: To complement the efforts of SBS Transit's staff on the ground, SMRT staff at interchange stations such as Dhoby Ghaut were seen directing affected commuters to bus bridging services and advising them on alternative transport routes.

What could have been better

Reminders that all bus rides from affected stations were free: Some commuters did not know they could board any SMRT and SBS bus - and not just the shuttle buses - for free at affected stations during the breakdown. Bus drivers were also unaware until told by SBS officials not to charge commuters.