UPDATED (26 Oct 20120, 3:40pm) Adds comments from commuters.
The Circle Line resumed service Friday after it suffered a total breakdown late Thursday evening that affected about 10,500 commuters and prompted the detraining of some passengers.
In a statement, the Land Transport Authority said that, based on preliminary investigation, the cause of the service disruption was a power trip at Promenade station that initially affected the entire Circle Line. The trip was likely due to faulty cable that was then isolated.
Train service was disrupted both bounds at 10:26pm.
About 100 commuters on a train that stalled in the tunnel between Promenade and Bayfront were detrained and guided to Bayfront within half an hour, LTA said.
According to SMRT, which operates the Circle Line, partial train service between Harbourfront and Paya Lebar stations resumed at 11:20pm.
Sections between Stadium and Dhoby Ghaut, and Stadium and Marina Bay remained closed for the rest of the evening to allow SMRT and the Land Transport Authority to isolate the fault, the firm added.
Bus bridging services were activated between Harbourfront and Dhoby Ghaut stations and the first bus arrived at Dhoby Ghaut at 11pm, it added.
Chia Chun Wah, vice president for the Circle Line, said SMRT has been working with LTA and manufacturers to change out all the power cables but that this would take time.
"To speed up the change out, we are considering the possibility of closing down certain stretches during off-peak hours and running alternative services to ensure minimal disruption to commuters’ journey,” he said.
SMRT said when the disruption starts it immediately activated its Rail Incident Management Plan.
Its crisis management team headed by SMRT president and CEO Desmond Kuek was at Kim Chuan Depot Operations Control Centre to provide guidance on incident recovery, while the Emergency Response team was on site to attend to recovery operations.
More than 280 staff were activated, including 49 service leaders recalled to provide bus bridging services, 30 engineers for recovery operations, 100 staff at the operations control centre and 100 customer service staff to assist commuters.
In a statement, Kuek apologised for the inconvenienced caused by the disruption.
For its part, LTA said it also activated its own crisis management team led by chief executive Chew Hock Yong was at the Land Transport Operations Centre to monitor and coordinate the incident management and recovery efforts.
LTA engineers were deployed to the incident site to help SMRT engineers with repairs. About 50 LTA officers were also deployed to assist SMRT on service recovery, crowd control and traffic management.
About 100 additional station staff and customer service team members were deployed on the ground to assist affected commuters.
SMRT said passengers who could not continue with their journey because of the disruption, or had to exit an SMRT train station without taking a trip but had their fares deducted, can get a refund at the passenger service centre in any of its 83 stations in the next 14 days.
However, despite their efforts, a few affected commuters told Yahoo! Singapore that SMRT could have done better informing people about the breakdown.
Jeremy Teo, 23, university student, said he was stuck at Botanic Gardens station and wasn't informed that alternative transport was provided.
"While it is good that SMRT does provide additional transportation like buses in the event of a train breakdown, I feel more can be done to let the public know where and how to get access to the buses provided by SMRT," he said.
Gabriel Goh, 21, a national serviceman, said when he entered Holland Village MRT station he saw signs near the gantry that train services were being extended for the night.
"Only when I was about to tap my card did this SMRT personnel inform me that there was no train service at all, which is so ironic. They could've removed the signs regarding train service extension and replace them with information regarding train disruption," he noted.
"On top of that, they could've deployed more personnel to manage the crowd and control the situation better," he added.