Comments by "Stephen Villano" (@spvillano) on "FOX 2 St. Louis" channel.

"Can't be an improvement, it's preexisting." "That's OK, we'll retroactively reassess for the back taxes owed".
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Episcopal Hospital in Philly was a stop in the underground railroad and has very similar tunnels going from building to building. While the tunnels weren't used for transportation beyond between buildings, they were used to house escapees between "stops". Then, the escapees would depart onto their next "stop" in the route via the time honored method of heel and toe express.
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@sideshowbob just watch it on the surface. The last wave of flying saucers has passed, it's advanced to flying cups and plates. I really hate going out when the neighbors are fighting...
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Episcopal Hospital in Philly has somewhat similar tunnels that were utility tunnels between buildings on the grounds and were utilized (and quite well documented at the time) in the underground railroad. Basically, they got used to briefly house escapees, actual travel was traditional overland heel and toe express. My impression is a WWII era sewage tunnel.
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@ThePookosh that depends upon sewage flow rate and amount, as well as what kind of mortar and bricks were used. The pointing is in excellent condition though, at what little I can see in detail, well within the 20th century for the brick type and type of mortar joint used. Looks like a channel sloped floor, judging from the debris and the few such tunnels I saw tended to be with small channels for their primary flow, typically never filling the width of the floor. That said, could just be drainage for a utility tunnel of some sort.
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