Plumbing and Sewer FAQ
Answers to common questions about Seattle side sewers, backups, permits and working with us. Don’t see yours? Call 206-593-3737.
Side sewers and sewer lines
What is a side sewer?
Seattle’s term for the private pipe that carries wastewater from a building to the public sewer main. Elsewhere it’s often called a sewer lateral.
Where does my responsibility end?
At the public main. SPU defines the side sewer as all piping outside the building footprint up to, but not including, the tee, wye or connection to the main. SPU’s consumer guidance also says owners are responsible for removing roots up to and within that connection.
Who issues side sewer permits in Seattle?
Seattle Public Utilities, since October 1, 2025. Applications go through the Seattle Services Portal. Repair permits are processed by the end of the next business day, according to SPU.
How much does a side sewer permit cost?
SPU lists sanitary repair permits on private property at generally $280 and drainage repair or addition/alteration permits at generally $375, each including one to two inspections. Right-of-way work also needs an SDOT permit with its own fees.
Do I need a permit to have roots cut out of my sewer?
No. SPU says root removal and unclogging don’t require a permit. Repairs and replacements do.
Who is allowed to work on the side sewer under the street?
Seattle code limits side sewer work in a public place (planting strip, sidewalk, street) to registered side sewer contractors, and the work also needs an SDOT permit.
Where can I find a map of my side sewer?
Use the City of Seattle side sewer card viewer (maps.seattle.gov/sidesewercardviewer). Cards are historical records, so confirm with a camera and locator.
Backups and emergencies
Sewage is coming up my floor drain. What do I do?
Stop using water, keep people away, turn off power to the area if it’s safe, and call a plumber. If the plumber suspects the City main, call SPU at (206) 386-1800.
Why call Puget Sound Energy before clearing a sewer?
SPU advises calling PSE at 1-888-225-5773 before clearing a side sewer blockage, to avoid damaging a gas line.
Can I get reimbursed for a sewer backup?
If an SPU sewer issue caused it, SPU says you can file a damage claim with the City. Document the damage and keep cleanup invoices.
What are your hours?
We’re available 6 AM–10 PM, every day (Pacific Time), and urgent calls are welcome during those hours.
Water heaters and plumbing permits
Who issues plumbing permits in Seattle?
Public Health – Seattle & King County issues plumbing and gas piping permits and does inspections in Seattle. Side sewers outside the building are permitted by SPU.
Is a permit required for a like-for-like water heater swap?
Yes, from July 1, 2026. Public Health – Seattle & King County now requires permits for all replacement water heaters, including like-for-like.
Is Seattle’s water hard?
No. SPU’s August 2025 analysis measured hardness of about 1.2–1.5 grains per gallon in its Cedar and Tolt supplies, which is low.
How do I check a plumbing contractor’s license?
Use Washington L&I’s Verify a Contractor tool. In Washington, plumbing contract work must be done by a licensed plumbing contractor with a designated certified plumber.
About working with us
How do I book?
Call 206-593-3737, or send a request through our contact page and we’ll get back to you.
Sources: Seattle Public Utilities: Your side sewer; SPU: Side sewer permits; SPU: How to apply for a side sewer permit; SPU: Side sewer repair methods; SPU: Sewer backups; Seattle Municipal Code ch. 21.16 (Side Sewers); Public Health – Seattle & King County: plumbing and gas piping permits; Public Health – Seattle & King County, April 2026 plumbing newsletter (water heater permits); SPU quarterly surface water analysis, Aug 12, 2025 (PDF); WA L&I: Licensed plumbing contractor requirements.
Need a plumber in Magnolia or nearby Seattle?
Call 206-593-3737, or send us a request online and we’ll get back to you.