WASHINGTON (AP) — The regional train system serving the Washington, D.C., area will remain on drastically reduced service levels through at least the end of this year, as authorities grapple with a safety problem that has forced the majority of the trains out of service.

Paul J. Wiedefeld, general manager of the Washington Metropolitan Area Transit Authority (WMATA), announced Monday that there were no set timelines for the return of the 7000-series train cars to service. The trains are the newest in service and the 748 cars comprise about 60% of the fleet.

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The Metro authority’s safety commission abruptly ordered the withdrawal of the entire 7000-series line of trains in mid-October after a derailing revealed chronic problems with the wheels and axles.

“We are intentionally not setting deadlines so that safety and good data drive our decisions, but we are mindful that customers want the best service we can provide as soon as we can deliver it, and we are committed to building back up in phases,” Wiedefeld said in a statement Monday.

The original plans to bring older 6000-series trains out of retirement to help fill in the service gaps have been delayed by the global supply chain crisis, which has prevented the arrival of necessary parts.

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“While we know service is not as frequent as customers would prefer, we will add each train as it becomes available to help incrementally improve service reliability and frequency,” Wiedefeld said.

The suspension of the bulk of Washington’s Metro fleet was prompted when a train car slipped off the tracks on the Metro’s Blue Line near Arlington National Cemetery on Oct. 12. The car had apparently derailed once and then re-connected with the rails by itself, before derailing a second time. Some passengers were trapped in a tunnel in a dark train car and had to be evacuated on foot.

After the derailing, the National Transportation Safety Board revealed that the Kawasaki-made 7000-series trains had been suffering an escalating series of incidents due to a design flaw that caused the wheels to spread too wide on the axles, allowing the carriage to slip off the tracks. The issue had been apparent to WMATA since 2017, but neither NTSB nor the WMATA board had been informed, said NTSB Chair Jennifer Homendy.

The incident remains under investigation by the NTSB. The incident has been an embarrassment for WMATA, which suffered a string of dangerous derailments and track fires several years ago but claimed to have addressed its issues.

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Overall rider numbers remain at about 30% of pre-pandemic levels but are expected to increase steadily as offices reopen and tourists return to Washington.

CBS Baltimore Staff