PWSA is the water and sewage provider for the city of Pittsburgh. With that said, PWSA is pretty expensive, and even more so to residential properties which apartment buildings likely fall in to that residential properties. With that said, FSP Realty will have a gray water tank under every building. Water from sinks, and showers will be collected din the gray water tank. This tank is to water any outdoor greenery, and will be used for the toilets of the respective building. This will reduce the sewage bill, and make sure that otherwise clean water is reused and put to good use. Needless to say, PWSA will likely be a large utility bill because of their higher rates to residential properties. With that in mind, you as the tenant should be mindful of your water and swage usage.
As for hardware, every building will have a backflow preventer. This will prevent the sewage from backing up in to the basement, and at least cause a cleaning and disinfection process. PWSA will not responsibility once they reach the meter. This includes their sewage backing up into the building.