Metro officials are taking a closer look at recent train derailments after a double derailment on the Red Line on Friday caused major delays throughout the weekend.
It was only the seventh such incident with passengers aboard in the transit system’s 33-year history, according to Metro spokesman Steven Taubenkibel.
But it marked the fourth set of derailments in less than two months, prompting Metro officials to take a harder look at the unusual string.
“We have to take a very close look at our practices internally,” Taubenkibel said. “We have to take a very introspective look.”
Red Line service returned in time for Monday’s morning rush hour.
Metro officials had been investigating each case that tied up commutes for thousands of riders. But now they are looking to see how they can improve rail infrastructure and maintenance systemwide.
Metro officials and experts call the recent spate of derailments highly unusual. The incidents occurred in different parts of the system, at different times and often involving different pieces of equipment.
Vukan Vuchic, a University of Pennsylvania professor of urban transportation, says transit systems can go years without a derailment, making such a group of cases rare. However, he said, Metro is a modern system with automatic safety features that protect its passengers. “It is probably one of the safest modes of transportation,” he said.
No one has been hurt in the incidents. The latest case, though, trapped 84 passengers in a train tunnel for more than an hour.
The incidents go back to a January 2007 derailment that injured 23 riders and led officials to call for improvements to the system.
Although the National Transportation Safety Board told the agency to install guardrails by this year, those upgrades had not been finished when a train derailed last month in the same area. The derailment happened just before the work was scheduled to occur, Taubenkibel said.
In the most recent case, he said, a broken piece of track appears to have caused the derailments, though it’s not clear what caused the section to break. Metro will send samples of the rail to a lab for testing, he said.
Just a week before, he said, Metro scanned the area with ultrasonic equipment that it uses five times a year throughout its 106 miles of track. It found nothing in the area.
That equipment may have prevented another case when it found a defect in the rail near the Capitol South station on the Orange and Blue lines early Monday. The transit system began emergency track work that extended into the morning commute. “We wanted to repair it as soon as we could,” Taubenkibel said.
Next year, the transit system will get a special vehicle that can evaluate the track for flaws.
