Plumbers
Who is responsible for fixing the sewer line between my Madison house and the City sewer main?
A common question, answered by the MadisonWI.com editors · November 9, 2026
1 answer
From MadisonWI.com
In the City of Madison, you are. City Engineering says homeowners are responsible for maintaining and repairing the private sanitary sewer service line, often called the lateral. That line runs from inside the home to the point where it connects to the public sewer main. The City's Engineering Division operates and maintains the public sewer system, including the main. The City says it's normal to clean sediment out of a lateral every one to three years. If yours needs cleaning more than once a year, contact Engineering so they can check for a bigger problem. If you have a backwater valve, maintaining it is also your job. This page covers sanitary sewer lines only. For questions about your water service line, contact Madison Water Utility, which is a separate City department. Other communities set their own rules. Source: City of Madison Engineering, Homeowner Responsibility (checked November 2026).
Written by the MadisonWI.com editors · November 9, 2026