NEW YORK (CBSNewYork) -- Human error was to blame for a computer glitch Thursday that forced Metro-North to suspend all trains on three of its five lines, Metropolitan Transportation Authority chairman and chief executive officer Thomas F. Prendergast said.
As CBS 2's Andrea Grymes reported Friday evening, the result of the glitch was a swarming crowd of stranded Metro-North and Amtrak passengers in Grand Central Station, and thousands more people trapped on trains.
Metro-North took full responsibility for the glitch.
"We deeply apologize to all of our customers who were affected," said MTA spokesman Adam Lisberg.
But as CBS 2's Jessica Schneider reported, the apologies were not good enough for everyone. Some were demanding much bigger consequences.
Around 7:45 p.m., the computers that run the railroad's signal system lost power when one of two main power supply units was taken out of service for replacement, Prendergast said.
Lisberg said the backup system that should have kept the power going the problem did not work.
"What we thought was the functioning backup turned out this disconnected wire, and it didn't have full functionality, and this cascaded into the whole railroad being shut down for almost two hours," Lisberg said.
As a result, more than 50 trains on the Hudson, Harlem and New Haven lines were brought to a stop for safety reasons as electricians worked to hook up temporary power and get the signal system back on track.
MTA: Human Error To Blame For Glitch That Suspended Metro-North Trains
The outage stranded thousands of passengers on trains and at Grand Central Terminal and other stations as they waited for nearly two hours for service to restored.
"Last night's failure was unacceptable, pure and simple," Prendergast said in a statement. "The project should have been analyzed for risks and redundancy before it began and it should not have been performed when thousands of customers were trying to get home in cold weather."
During the outage, rail traffic controllers instructed all engineers to bring their trains to the nearest station and allow passengers to exit if they wished.
But that did not work for every train. If an interlocking was on the route before a station, the train stopped at the interlocking and passengers were stuck on the trains.
Metro-North said all trains had power and heat during the interruption.
"All of our customers who were stranded on these trains, nobody was at any risk. The trains all had heat, light and power," Metro-North spokesman Adam Lisberg told 1010 WINS. "The problem was with the signal system, so we couldn't move trains without signals, but nobody was ever in any danger."
Cause Of Computer Glitch That Suspended Metro-North Lines Remains Unclear
Crews were able to restore power around 9:30 p.m. and service slowly resumed, but residual delays lasted well into the night.
"Metro-North customers deserve better, and I extend my sincere apology to all of them," Prendergast said. "I have directed Metro-North to bring in an independent consultant to examine how and why these mistakes were made and to recommend any necessary changes to operating procedures to ensure nothing like this ever happens again."
Lisberg also called what happened Thursday "unacceptable" and said the agency would learn from its mistake.
"We should have not done a project with this kind of risk without doing an analysis of the risk and we shouldn't have done this when thousands of customers were still trying to get home," he said. "Our customers deserve better, we apologize to them, we're going to get better."
The ordeal caused several elected officials to demand an explanation.
"I'm convinced people know they have to do better, and we'll certainly be in close communication with the MTA," said Mayor Bill de Blasio.
U.S. Sens. Charles Schumer (D-N.Y.) and Richard Blumenthal (D-Conn.) released a statement criticizing Metro-North.
"This is at least the second time where human error, poor planning and a lack of back-up power have caused a significant breakdown on the Metro-North railroad. This time it had a significant impact on tens of thousands of commuters on one of the coldest days of the year. Whether it is safety or repair work, Metro North owes its commuters an explanation, and has to get its act together."
Speaking to reporters later, Schumer said serious action needs to be taken.
"Heads should roll," he said. "Something is wrong here."
Schumer and Blumenthal want the Federal Railroad Administration to expand an existing investigation following a deadly derailment last month to include the service shutdown on Thursday night.
And Connecticut Gov. Dannel P. Malloy said there was "really no excuse for what happened" and said those responsible must be held accountable so similar issues are avoided in the future.
"Anybody in their right mind would have said why not do that in the middle of the night as opposed to 7 p.m. when we're still handling heavy commutation traffic. It was the lack of common sense that caused this to happen," Malloy told WCBS 880 Friday afternoon. "We have to assure the public that common sense is going to be applied to these kinds of decisions in the future."
Malloy called the incident "totally avoidable and frankly, unfathomable given that it occurred due to inappropriate actions on the part of Metro-North."
Call For Better Oversight On Metro-North
Passengers were not happy either.
"I don't expect a perfect world, but I'd like a little more order -- that's all I'm asking," said Wickford Welden of Larchmont.
Welden was among the masses inside Grand Central Station Thursday night, waiting for answers and his train.
When he learned that human error was to blame for the problems, Welden called it yet another failure of what he described as a dysfunctional MTA.
"There's got to be some supervision about what people are doing," he said.
Commuters said Metro-North is increasingly unreliable, Schneider reported. Even Friday night, there were delays on several lines.
"Maybe we need some more checks and balances with MTA, so this doesn't happen?" said Ana Charalambides of Harlem.
On Wednesday, nearly 200 passengers were stranded on the New Haven line when the winter weather caused downed wires in Connecticut.
In December, a high-speed train derailed near the Spuyten-Duyvil station in the Bronx, killing four passengers.
In September, a botched power station maintenance project affected New Haven line service for 12 days, forcing the railroad to severely limit service.
In July, a freight train derailed on Metro-North tracks in the Bronx.
In May, two trains collided in Connecticut, injuring more than 70 in Bridgeport.
Also in May, a controller mistakenly gave the green light to a train that roared through a work zone and killed a track supervisor in West Haven.
"If you combine this with the recent downed power that lasted about a week's time late last year as well as some of these other incidents that have happened, I think the Metro-North has to go a long way to recovering the faith of the people in their ability to do this job," Malloy said.
Another Connecticut lawmaker said the recent problems on Metro-North point to the need for better oversight.
Connecticut state Sen. Toni Boucher (R-Bethel, New Canaan), who has been considering a run for governor, said a new president about to take over at Metro-North presents a good opportunity to establish an oversight committee to help boost training and emergency response.
"There should be an oversight board that should be put in place until they can change their process and procedures to assure reliability, safety, particularly of the commuting public," Boucher said. "Weather-related problems are part of their business. That's what we have in the northeast, we always have weather conditions that can be extreme and uncertain and they should be prepared for every eventuality."
U.S. Rep. Jim Himes (D-Conn.) has also been in touch with the current Metro-North president Howard Permut. Himes said Permut will advise him on how the railroad plans to improve rail safety as well as communications with its passengers.
A Metro-North representative called the recent problems an "unfortunate series of unrelated events."
CBS 2 asked about whether commuters inconvenienced this week would be reimbursed. The MTA said there are no plans right now to do so.
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