Side Sewers

Maintenance and Repair of Side Sewers

The side sewer is the sewer pipe that connects a building to the sewer main located in the street. Property owners are responsible for maintenance and repair of side sewers.

The City is responsible for sewer mains if they are located in public rights of way, like streets, or a utility easement dedicated to the City. This information is also found in the Issaquah Municipal Code 13.36.010 and the Issaquah Sewer Plan Update (PDF) section 3.1.

Sewer Main Analysis

The city performs an analysis of the sewer mains every few years as part of the Sewer System Plan Update (PDF). This analysis identifies which ones are near the end of their service life, are prone to infiltration, root clogs, sudden failures or cannot provide the required flow capacity. The City also conducts television video inspections of the sewer system.

City ratepayers pay for the ongoing replacement and maintenance of existing lines in the sewer system. In some cases, the City may extend a sewer into a neighborhood, and in other cases a developer build may extend a segment. In either case the party who hooks up to that new sewer segment pays their fair share of the construction cost in addition to normal hookup fees.

The City allocates yearly budgets to rehabilitate sewer mains and extend new line into areas that are not currently served by sewer.


The Public Works Sewer Division routinely maintains the sanitary sewer mains to keep them flowing freely. Our crews inspect and clean the sanitary sewer mains on a scheduled basis, but there are sewer do's and don'ts that you can follow to keep your home's sewer system as well as the City's sewer system trouble-free. Wise use of the sewage system and performance of simple preventive maintenance will help safeguard the system and reduce costs for everyone.


If you have any other questions or concerns, feel free to contact Public Works at 425-837-3470.