Common Laterals

A common (shared) sewer lateral is a privately owned lateral that serves more than one property. Ordinance 100 (Section 13. Shared Laterals) does not allow the construction of new common laterals, a prohibition established in October 1993. Properties throughout the District served by common laterals installed before this prohibition are allowed as part of our legacy system.

The Ordinance also gives the District permitting authority to require common sewer laterals meet District standards. Homeowners with common laterals are encouraged to discuss entering into maintenance agreements between all owners served by a common lateral in order to maintain, repair and/or replace the common lateral.

Without such an agreement, homeowners that have common laterals are generally responsible for the entire portion of the lateral on their property, up to the next downstream lateral connection (Example #1). This may include where it crosses onto another property, whether there is a recorded easement or not (Example #2). Homeowners with the furthest downstream lateral connection are responsible for the remaining portion of the lateral, including the connection to the public sewer main (Example #1 & Example #2).

Where a property owner has a separate lateral (not shared) that connects directly to the public sewer main, that owner is generally responsible for the entire portion of the lateral on their property, which may include where it crosses onto another property, whether there is a recorded easement or not (Example #2).

DISCLAIMER: The information contained within the above examples is for general illustrative purposes only and should not be relied upon for any particular property, or as a basis for any financial or other commitments. Property owners are strongly encouraged to consult with an attorney and/or other professionals regarding site-specific conditions and obligations.

Having a cooperative approach in place for when maintenance, repair and inspection work need to occur on a common lateral is beneficial. In these circumstances, homeowners are encouraged to use one contractor that is licensed, qualified and knowledgeable about the District's standard specifications for completing lateral repairs across multiple properties.

The District recommends checking the California Department of Consumer Affairs Contractors State License Board before hiring any contractor. For more information about local contractors, you can view the District's local contractor list here.. A cooperative approach among property owners in addition to hiring a knowledgeable contractor will ensure all work completed will be compliant with District standards. Repairing and replacing outdated common laterals helps sustain public and environmental health by preventing overflows and backups.

Please note: Common laterals do not qualify for Grant or Loan funding, as they do not conform with District specifications or the Uniform Plumbing Code (Section 721.1), which requires laterals from each property to connect directly to the public sewer main. Funding is available to homeowners that choose to disconnect from a common lateral and install a new, separate lateral connection(s) to the public sewer main as shown in (Example #2) above. In this case, the District will not require an additional fee to make the new lateral connection to the public sewer main. More information on funding and eligibility can be found by clicking the link here. 

While common laterals are the homeowners' responsibility, the District is always here to talk with you about your sewer lateral and answer any questions you may have. Email Administrative Staff or call our main line at 415-259-2949. Our business hours are Monday through Friday, 7:30 a.m. to 4 p.m. Calls and emails received after hours are answered the next business day. Emergency calls will be routed to our on-call staff for immediate assistance.

If you’d like to learn more about applying and obtaining a District permit for work on your private sewer lateral, visit the Permits webpage.