Sewer Lines (Water Drainage System)

How A Sewer Line Works

Most homes have a drain-waste vent (DWV) system that removes sewage and greywater from fixtures such as toilets, sinks and showers. This water exits through a “trap”, a “u” shaped section of pipe that contains water. This prevents foul odors from coming back up into the house. Through these traps, all fixtures are connected to waste lines. which in turn take the waste to a “soil stack” or vent pipe. This pipe is attached to the lowest point of your plumbing and runs out through the roof.

House sewer: A section of pipe running between your drainage system and the public sewer system or your septic tank.

House drain: The lowest piping in a house drainage system, this pipe receives the discharge from soil, waste, and other drainage pipes, then carries such discharge to the house sewer.

Soil stack and pipe: A line of pipe that removes dirty water from toilets.

Waste stack and pipe: Pipe that removes discharged water other than from toilets (greywater).

Trap: A u-shaped device that prevents odors from waste to escape into the house.