no it will die, in ****.
Hopefully. It depends if it will be able to survive through all the waste in the sewers, and if it can find it's way to the ocean. Most sewers lead to a cleaning facility, so yeah. :/
How big is the fish?
Maybe it could wear a gas mask.
At my house it will end up in the septic tank...
After some extreme research (re-watching Finding Nemo) I conclude that yes. Yes they will.