A sanitary sewer lateral is a pipe that carries sanitary waste from the plumbing system in a home or business to the public sanitary sewer main. The upper sanitary sewer lateral is located on your private property while the lower sanitary sewer lateral and public sanitary sewer main is typically located in a public right of way (public streets) or a dedicated County easement located on private property. Sanitary sewer laterals are typically 4" to 6" in diameter and public sewer mains are 8" and larger in diameter.
The upper sanitary sewer lateral is an underground pipe that is part of your home’s plumbing. It is also referred to as a private sewer line or private sanitary sewer lateral. If you own your home, you also own the upper sanitary sewer lateral from the end of your home’s internal plumbing to the property line. You are responsible for maintaining your lateral, just like other pipes in your home.