Seattle Public Utilities Mami Hara, General Manager/CEO

Side Sewers

side sewer

What is a side sewer? What does it do?

A side sewer connects the plumbing in a building to the public sewer in the street. It carries wastewater from a building’s sinks, toilets, and drains to the public sewer.

Side sewer ownership and care

If you own your home or building, you own your side sewer all the way to the public sewer main.

You can get specialized information (on selected parcels) within the Seattle city limits via a side sewer card, lateral map, and aerial photographs from the Seattle Department of Construction Inspection. Call (206) 684-5362 for more information.

No trash in the toilet

Do not put trash, any sort of wipes, or debris in toilets. Trash clogs toilets, side sewers and even City infrastructure. Watch this SPU pump station video to see what happens when trash is flushed.

Side sewer problems

Sewer backups

Troubleshoot common sources of sewer problems

  • Offset joints. Uneven connections between pipe segments can lead to sewer problems.
  • Sagging pipes. If a side sewer line dips down, a backup is possible.
  • Cracks and fractures in pipes. Due to poor installation, poor soil bedding, root penetration or structural deterioration.
  • Debris/grease in pipes. Grease, fat, oil, wax and other debris contribute greatly to sewer problems.
  • Holes in pipes. Can cause surrounding soils to erode into the pipe or cause debris buildup in the pipe.
  • Root damage. Tree roots can penetrate older clay and concrete pipes.
  • Exposed aggregate. Most common critical defect in side sewers constructed from concrete.

Inspect and repair a side sewer

  • Have someone take a look
    Find a plumber or sewer inspector who can run a video camera through your side sewer.
  • Make a repair
    If you need to repair your side sewer, you will need a side sewer permit from the City of Seattle to complete this work.
  • Money for repairs
    The Seattle Office of Housing offers Home Repair Loans for low- to moderate-income families in owner-occupied, single family homes.