Side sewer permits in City of Seattle: fees, timeline & requirements (2026)
Everything you need to know about pulling a side sewer permit in City of Seattle, Washington — when one is required, what it costs, how long review takes, what documents are required, and which inspections you can expect. Cited to Seattle Public Utilities (SPU).
Free lookup, no account needed — your lot polygon, zoning, setbacks and overlays, cited to City of Seattle's source.
When does a side sewer need a permit in City of Seattle?
The side-sewer permit is issued by whichever utility owns the sanitary sewer — the city, a sewer or water district, or a regional utility — under that utility's own code, with WAC 51-56 (2021 UPC) governing how the building sewer is laid. WHICH UTILITY IS A PER-PROPERTY FACT: a lot can sit inside a city for permitting and outside its sewer district, so confirm the owner of the main before applying. Triggered by a new connection, repair of more than about 2 ft of pipe, relining (CIPP), or capping at the property line for a demolition.
From City of Seattle's own code
“A. It is unlawful to connect any property or premises to a sanitary or combined sewer, or storm drain, or to construct or to make repairs, alterations, additions to, or to abandon, remove, or cap any side sewer or service drain connecting to the sanitary or combined sewer, or storm drain, without first applying for and securing a permit for such work from the Director of Seattle Public Utilities and without first paying the fee as prescribed by Director's Rule.”Source ↗verified 2026-09-07
Required submittals
- site plan with sewer line route
- depth + slope detail
- cleanout locations
- utility locate ticket
Inspection sequence
- pre-cover (open trench)
- air / water test
- final
Contractor specialties needed
side-sewer-contractor
Who can do this work in City of Seattle?
Kolmo Construction is a licensed Washington general contractor — KOLMOL*753JS, active through April 10, 2027, bonded and insured — working throughout City of Seattle and King County. Kolmo prepares the drawings and submittals, files the side sewer permit with Seattle Public Utilities (SPU), carries the project through review and inspections, and performs the construction. Call (206) 410-5100 for a City of Seattle side sewer quote.
Notes & caveats
Issuing body is the sanitary sewer utility, NOT the building department, and inspection is the utility's too. SOME utilities additionally require the contractor to hold a side-sewer card or registration before they will issue; it is not universal, so check the serving utility's own rules rather than assuming either way.
How to apply yourself
- 1. Confirm your parcel's zoning & overlays. Run an address lookup for your City of Seattle side sewer — we'll pull your specific lot polygon, zoning, setbacks, and any shoreline/ECA/historic overlays.
- 2. Assemble submittals (4).
- 3. Apply with Seattle Public Utilities (SPU).
- 4. Track review. Respond to reviewer comments promptly.
- 5. Pay issuance fees (Side-sewer permit fees are set by the utility that owns the main; some add a depth-based surcharge. Utility-issued, not building-permit-issued.) and pick up the permit. Inspection card travels with the job.
Or have Kolmo do it
We pull side sewer permits in City of Seattle every month. We prepare the drawings and submittals, file with Seattle Public Utilities (SPU), handle reviewer comments, and build the project.
Licensed WA general contractor KOLMOL*753JS · bonded & insured
Side sewer permits in City of Seattle — FAQ
When does a side sewer need a permit in City of Seattle?
The side-sewer permit is issued by whichever utility owns the sanitary sewer — the city, a sewer or water district, or a regional utility — under that utility's own code, with WAC 51-56 (2021 UPC) governing how the building sewer is laid. WHICH UTILITY IS A PER-PROPERTY FACT: a lot can sit inside a city for permitting and outside its sewer district, so confirm the owner of the main before applying. Triggered by a new connection, repair of more than about 2 ft of pipe, relining (CIPP), or capping at the property line for a demolition.
How much does a side sewer permit cost in City of Seattle?
Side-sewer permit fees are set by the utility that owns the main; some add a depth-based surcharge. Utility-issued, not building-permit-issued.