One of the busiest F-line stops, Wharf-bound at Fourth and Market, is too narrow to allow an ADA ramp, thus denying access to disabled people. That’s because the boarding island, which predated ADA and is thus "grandfathered," sits parallel to a BART/Metro escalator entrance, which narrows the street. Moving some downtown F-line stops to mid-block would allow wider islands with ADA access and faster boarding for all riders, while leaving more space for other street users by removing the current constrained islands.
