Who is responsible for sewer repairs?

Napa Sanitation Department (NSD) maintains all public sewer mains, and lower laterals within its service area (PDF), which includes the City of Napa and certain surrounding unincorporated areas. This includes 270 miles of sewer mainline that are generally located within public streets or easements dedicated for Napa Sanitation District use.

Each residential or commercial building has a separate connection to the public sewer main line which is called a sewer lateral. Each sewer lateral has two components:

  • Lower lateral (District’s responsibility)
  • Upper lateral (Property owner’s responsibility)

The Sewer Mainlines and Laterals diagram (JPEG) illustrates the difference between the property owner’s sewer lateral and the District’s lower lateral and sewer main lines.

It is the property owner's responsibility to maintain and repair the upper sewer lateral from the house to the property line cleanout (indicated in yellow in the linked diagram). Napa Sanitation District maintains the lower sewer lateral and main line (indicated in green in the linked diagram). The cleanout is typically located behind the property line and is the connection point between the upper and lower lateral. This cleanout is designed to go one direction (downstream) and cannot be used by homeowners or plumbers to clean the upper lateral. The cap on this cleanout is designed to fit loosely, allowing it to come off in the event of a backup in the lower lateral or sewer main.

An exception to this division of ownership is in areas where pipes were slip-lined by the District and the cleanout at the property line was removed. In that case, the District maintains the lateral all the way to the cleanout near the building. Unsure if your property falls into this category? Call the District at 707-258-6000.

Show All Answers

1. Who is responsible for sewer repairs?
2. How can I find out where a sewer problem is?
3. Sewage is backing up into my house/building through overflowing toilets, sinks, bathtubs, dishwasher, and/or washing machines. What should I do?
4. Sewage is overflowing from a cleanout or manhole onto the ground, driveway, street, etc. What should I do?
5. What is the difference between the sewer system and the storm drain system?
6. I have slow drainage through my toilets, showers, and sinks. What can I do about it?
7. I paid a plumber to repair my sewer lateral line. It turns out the problem was occurring in the public sewer line. Can I be reimbursed for my plumbing bill?
8. How do I proceed with a sewer lateral repair problem?
9. How can I avoid damage to other utilities during repairs or construction?
10. A contractor or utility worker broke my sewer lateral or sewer main line. What should I do?
11. Is there information available on the history or cleaning frequency of a sewer line?
12. There is a manhole cover in my neighborhood that rattles every time a vehicle drives over it. What can I do about it?
13. What can I do about terrible sewer odors?
14. How can I get a sewer clean-out installed?