The latest: Metro restores service on disabled lines, but only single-tracking

Metro said Thursday morning’s derailment of a train may have been caused by a problem at an interlocking — an area of track where trains move from one track to another– between the Federal Triangle and Smithsonian stations.

Officials stressed that the exact cause is still under investigation.

“It could be a problem with the infrastructure of a switch, it could be rail car related, it could be human error. Right now we don’t know the cause,” said Metro spokesman Dan Stessel.

The train was performing what is considered a routine daily move.

The train is believed to have left the New Carrollton rail yard shortly after the system opened at 5 a.m. It was headed westbound, but was going to switch over to the eastbound track near the Federal Triangle stop and become a Blue Line train headed to Largo station. It was to pick up its first passengers of the day at the Smithsonian stop.

But something went wrong and the train got stuck as it was moving through the interlocking between the Federal Triangle and Smithsonian stops. The operator stopped within the interlocking, an area on the tracks that includes signals and switches. Part of the train was on one track and part was on the other.

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“As it is making its move through the interlocking, the front car is on the eastbound track and the tail end is on the westbound track because it hasn’t passed through the switches yet,” Stessel said. But the train stopped in the interlocking, so part of the train is on the eastbound track and part of it is on the westbound track, he said.

The train had six rail cars and three of them went off the track. The train had several of the oldest rail cars that are part of the 1000- and 2000-series.

For riders, it meant more stations were impacted: Because there are few spots on the rail system where trains can turn around, Metro had to extend the area where service on the three lines was suspended, including two of the system’s main transfer points, Metro Center and L’Enfant stations.

Metro had no trains running between the Federal Center and McPherson Square stations — two spots where there are interlockings for trains to turn around, officials said.

This interlocking is seen on Metro’s Silver Line. It’s similar to the interlocking in downtown D.C. where a non-passenger train derailed Thursday morning. (Courtesy WMATA)

“There is no good way to turn trains around elsewhere in that area,” Stessel said.

The suspension forced not only riders of those lines, but also riders of the Yellow, Red and Green lines that normally transfer, onto packed shuttle buses to make the final leg of their morning commute.

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Metro said its service in the evening rush hour could also be impacted.

Metro said it would use a prime mover, which is a heavy piece of machinery, to get the train back on the track. It is not immediately clear how long it will take to get the train back on the track, out of the area and get service back to normal operations.

Metro said their initial reports are that the damage is relatively minor but they will know more once they’re able to move the train and re-rail it onto the tracks. They said they have to be careful not to cause further damage to get it back on tracks.

“We have brought in all resources from across the system to assist with the re-railing process, and to get it done as quickly and safely as possible,” said Jack Requa, Metro’s acting general manager.