I heard a thing in NYC was the immigrants could look for work, and if they didn't find anything they could go to the shore, get enough oysters to survive, and keep going.
So apparently that piss smell wasn't actually from the open sewage.
It was because before cars took over horses were the primary mode of transport for people who could afford it, and horse piss is absolutely rancid smelling if it lands on something that doesn't just absorb it like dirt or soil.