Electric Arcing Sparked Monday’s Metro Incident. And It Happens More Often Than You Might Expect.

Metro, which rarely inspires much public confidence on normal days, will be picked apart in the coming weeks and months after an incident Monday near the L’Enfant Plaza station left one passenger dead and more than 80 others hospitalized when a Green Line train stalled in a tunnel and filled with smoke.

While the Washington Metropolitan Area Transit Authority is deferring to federal regulators on the investigation into what happened yesterday, the immediate cause—electric arcing—is something the transit system has dealt with before, and without deadly consequences. Arcing is the result of a plasma discharge, and actually happens fairly often on Metro, according to a 2013 report, but rarely with any serious consequences.

Metro got a scare about electric arcing back on January 30, 2013, when a segment of the Green Line near Anacostia lost power after an insulator supporting the electrified third rail experienced electric arcing, causing several trains to shut down and spewing a cloud of smoke. Like yesterday, the 2013 incident happened right at the beginning of the afternoon rush hour, sending commuters into a tailspin. Also like yesterday, passengers aboard a train several hundred feet away from the nearest platform “self-evacuated” and navigated their way through darkened tunnels.

While Metro applauded the perfomance of most of its personnel that day, the transit agency’s follow-up report still showed several failures. While passengers on one of the stalled trains commended its operator for keeping people calm and informed, many riders from the other complained about being stuck in the literal and figurative dark during their ordeal. As many as 150 of them eventually got off the train themselves and walked back before officials could reach them, more than an hour after the power went out. The report also noted that arcing insulators occur an average of twice per month.

So why was yesterday’s emergency so much worse? That won’t come out until the National Transporation Safety Board completes its investigation, but the immediate evidence is unsettling. Besides the frequency of electric arcs, Metro also experienced a sharp increase in the number of smoke- and fire-related incidents between 2013 and 2014, NBC4 reported last July. There are about 100,000 insulators spread across 117 miles of track, and many of them need replacing; Metro put out a request for proposals last February for bidders to replace as many as 35,000 of them over a five-year period.

Yesterday’s scene resulted in the first passenger fatality since the 2009 Red Line crash near Fort Totten that killed eight riders and one train operator. And Monday’s incident shared some elements of that grisly event. Some of the cars on the smoke-filled train that was stuck about 1,100 feet from the L’Enfant Plaza platform were 1000-series stock, the oldest in the system’s inventory and equipment that the NTSB demanded Metro rid itself of after the Red Line disaster. When the NTSB files a report on Metro’s latest accident, there may be yet another citation about an outmoded fleet.

Metro was supposed to start rolling out its newest cars, the technologically advanced 7000 series, by this month. But safety inspectors representing DC, Maryland, and Virginia recently faulted the transit agency on its safety inspection protocols, potentially delaying the rollout and leaving Metro passengers riding old rail cars on tracks in need of repair.

Benjamin Freed

Staff Writer

Benjamin Freed joined Washingtonian in August 2013 and covers politics, business, and media. He was previously the editor of DCist and has also written for Washington City Paper, the New York Times, the New Republic, Slate, and BuzzFeed. He lives in Adams Morgan.