(Charles Dharapak/AP)

The event was postponed in August because of Hurricane Irene. Metro said it was postponing its scheduled work on the tracks for Sunday, Oct. 16, the day of the event.

Metro had planned to work on the Red, Blue, Yellow and Orange lines. Part of the Red Line was also going to be closed between New York Avenue and Fort Totten stations.

“We will adjust our plans to accommodate the rescheduling of this one-in-a-lifetime event,” said Richard Sarles, Metro’s general manager, in a press release. “While the rebuilding efforts of the Metrorail system are critical, we recognize the national significance of this event and will reschedule our work for a later date to ensure that customers have a seamless travel experience.”

Metro is spending $5 billion over the next six years on a massive capital improvement plan. Part of that involves repairing and rebuilding track work and implementing recommendations from the National Transportation Safety Board, following the 2009 fatal crash on Metro’s Red Line.

On Oct. 16, Metro plans to open at 5 a.m, two hours earlier than normal, operate eight-car trains and offer free parking at all rail stations.

The transit authority said it plans to have “customer service ambassadors” on hand at stations to help guide people to the memorial.

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