Quick warning and explainer: These are merely conceptual drawings from MassDOT that will probably never become reality. Also, the front exterior of the station is historically protected. The above design sketch, via MassDOT via the BBJ, shows the back side of the station along Fort Point Channel.
The bottom line: The state is gearing up for a possible (or probable) increase in the number of tracks it can handle at South Station, so some sort of massive renovation project is going to be needed if, or when, that occurs way down the road.
File under: Train Kept a Rollin’