WHen I was young I remember my grandmother having to put a plug type contraption in the basement floor drain because of water coming in when there were heavy rains. I can't say for sure but it would not surprise me that that drain ended up in the sanitary sewers. I do not think there were sewer plant back then as the general consensus was that the river could simply wash all sewage away.
I also remember fish being in the cooling water at the old coke plant and being told the water came straight from the river. I never saw a drain though but maybe they used all the excess in the quencher thinking on this and the bug rusty spots on the horizontal surfaces of many a car in the area back then.