Tell me about the sewer

[Birdmonster]

Millions,
So it was dumping yesterday in San Francisco and I was wandering towards the bus stop and started thinking about the gutters. Yes, my mind was in the gutters, ladies and gentlemen. I just started contemplating how genius the whole idea of a sewer system is. It's like traffic regulations; one of those things I've lived with all my life, taken for granted, but have never really stopped to think about. All those gutters, the water rushing off meaningfully underground, then that water going...somewhere else.

See. The thing is: I don't know the first thing about the sewer system. I raced little tin foil boats in the gutter when I was a whippersnapper, but my expertice more or less ends there. Things like, who first devised one? and does the water really just go straight into the ocean, like those crude spray painted admonishments say it does? I just want to learn a little about the sewers.