Home Improvement

My daughter is renting the basement apartment of a 100-year-old home. It's a fairly decent little place. Except for this. Can someone please tell me why there are cast iron pipes cut open, with air registers over them? Yesterday during the storm they were all full of flowing water. I checked a couple of them and they were all the same, cracked open cast iron pipe under the floor registers. What is going on here? I have more pictures if needed.

Edit: everyone, I'm grateful for all of the suggestions. Once she's finished unpacking, I'm going to do some investigating. It does not smell. .the water running thru it looks crystal clear. Well figure it out. Maybe.