A building sewer (sometimes referred to as a sewer lateral or house lateral) is the pipeline between the County sanitary sewer line, which is usually located in the street, and the indoor plumbing. County sanitary sewer lines have a pipe inside diameter of 8″ or greater while building sewers have a pipe inside diameter of less than 8″. Generally, residential building sewers have a pipe inside diameter of 4″ while building sewers for business establishments have a pipe inside diameter of either 4″ or 6″. The residential building sewer is owned and maintained by the property owner even if it extends into the street or public right of way.
