The transit network in the nation's capital remained hobbled Tuesday morning following an electrical malfunction that filled a busy subway station with smoke, killing one woman and sending dozens of people to hospitals.
The National Transportation Safety Board was investigating the accident, which happened at the beginning of the Monday afternoon rush hour and led to the first fatality on Washington's Metro system since a 2009 crash that killed eight passengers and a train operator.
NTSB investigator Michael Flanigon told reporters late Monday night that an electrical "arcing" involving the high-voltage third rail led a train to stop in a tunnel and quickly filled the tunnel with smoke. An arcing occurs when electricity from the third rail comes into contact with another substance that conducts electricity, such as water.
While there was water in the tunnel, Flanigon said the cause of the arcing was not yet known.
"The third rail is high-voltage direct current, and if that current starts arcing to another conductor that it is not designed to connect with, you get a flash," Flanigon said. "In certain cases, that arc can start sort of feeding on itself, and it actually generates gases that are more conductive."
Witnesses described a chaotic scene aboard the train as passengers tried to escape the smoke, and many passengers left the train on their own before emergency responders arrived on the scene, Flanigon said. In addition to the woman who died, whose name had not been released as of Tuesday morning, at least one other passenger was in critical condition at a local hospital. Eighty-four people were taken to hospitals, most with smoke inhalation, authorities said.
"It started to get scary pretty quick," passenger Jonathan Rogers told The Washington Post. "People started praying. Smoke was coming in pretty steadily."
The accident occurred around 3:30 p.m. Monday on a Virginia-bound yellow line train that had just left the L'Enfant Plaza station in downtown Washington, one of the system's busiest stations. The train stopped about 800 feet beyond the platform, and the arcing occurred roughly 1,000 feet beyond the train, Flanigon said. The train did not derail, and there was no fire, he said.
The yellow line remained shut down Tuesday morning, and the system's orange, blue and silver lines were on a reduced schedule. Service on the green and red lines was normal.
The Metrorail system, which connects downtown Washington with the Maryland and Virginia suburbs, carries an average of 721,000 passengers each weekday.
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Statement from Metro Board Chair Tom Downs to Metro customers:
"On behalf of the Board of Directors and all Metro employees, I offer my deepest condolences to the family of the passenger who died yesterday following the incident on the Yellow Line. To those who were injured or frightened, and to the thousands who have been inconvenienced by this major service disruption, I offer a heartfelt apology. Please also know that Metro is working to restore full service as soon as possible."
"Metro is actively cooperating with the National Transportation Safety Board investigation that is now underway. This will be a thorough process that often takes time, and we understand that passengers want answers quickly. Please know that once the cause of this incident is understood, we are prepared to take the actions needed to prevent this from happening again. The safety of each and every Metro rider and employee remains our absolute highest priority."
"We are all saddened by today's fatality aboard the Metrorail, and our thoughts and prayers go out to the family of the passenger who passed away. I want to thank our brave first responders who assisted passengers during the evacuation and with treatment at the scene. I have been in contact with the WMATA leadership, and we will continue to keep the District's resources available in the aftermath of the incident."
Representatives Gerry Connolly and Don Beyer issued the following joint statement in the aftermath of Monday's Metro Tragedy:
"We are heartbroken at the news of today's troubling events on Metro and await a clear and thorough investigation of the events that led to today's tragedy. No one should fear for their lives on their commute. Our thoughts and prayers are with the victims and their families. We will work with Metro and the NTSB to pursue the cause of this tragedy so that Metro can work to ensure it does not ever happen again."
Metrorail service information for Tuesday, January 13
Updated: 4:55 a.m. / January 13, 2015
Metro is advising rail customers of the following service changes for Tuesday, January 13, following today's incident at L'Enfant Plaza:
All Yellow Line service will be replaced with additional Blue Line trains operating between Huntington and Largo Town Center, via Rosslyn. Trains on this route will depart every 12 minutes. Use Green Line trains for service between Greenbelt and Downtown DC.
Blue Line trains between Franconia-Springfield and Largo Town Center will operate every 12 minutes.
Orange Line trains will run every 8 minutes between Vienna and New Carrollton.
Silver Line trains will run every 12 minutes between Wiehle-Reston East and Largo Town Center, with many trains expanded to 8-cars long to provide additional capacity.
Green Line trains will run normal service every 6 minutes between Branch Avenue and Greenbelt.
Red Line service is unaffected and will operate on a regular weekday schedule.
A limited shuttle bus option is available between Pentagon and L'Enfant Plaza, running every 20 minutes. Board shuttle buses from Pentagon on the lower level of the Pentagon bus bays; from L'Enfant Plaza at 7th & C St SW.
FOR UPDATED SERVICE INFORMATION, PLEASE CHECK OUR ALERTS PAGE.
Regular Metrobus and Circulator bus service may provide a good alternate travel option for some riders. To check, use the Trip Planner at wmata.com and select the "bus only" option.