While the garage is far from the oldest in the Metro system, for years it has been high on the list of those in poor condition. Part of the garage has been closed off to parking since 2015 due to other structural concerns, leaving about 300 spaces available.
This week, engineers found more areas of the garage where concrete could come loose and fall, Metro said.
The south station entrance and pedestrian walkway to the station will remain open, as will the two other Metro garages at the station.
All cars currently parked in the garage must be removed no later than 5 p.m. on Sunday, Aug. 12.
Metro is still developing plans to replace the garage after it is demolished.
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