How To Care For Your Side Sewer

Many people don’t encounter a side sewer until they begin the process of buying a home. The side sewer line collects drain water, waste water, and human waste from the home’s kitchen, bath, laundry, and toilet. This main drain flows into the city sewer line and then to the nearest pump station. As a homeowner, you want to make sure you care for your side sewer line and keep it operating efficiently.


The City of Seattle defines the side sewer as: “a pipe system that carries wastewater and/or drainage water from the plumbing and downspouts of your building to the public sewer system or outlet. This includes the pipe system up to, but not including, the connection to the public main. A side sewer includes all the piping located outside the building footprint. The entire side sewer is owned and maintained by the property owner.”

Care & Maintenance

If you recently purchased a home in Seattle, you most likely had the side sewer videoed and inspected before completing the sale. This inspection is important because, as the above paragraph says, the side sewer is owned and maintained by the property owner.

The side sewer video and the inspection results should show a clear line with no breaks, obstructions, or bellies. (A belly is when part of the line drops below grade and collects debris.) In addition, the video shows the location and length of the side sewer in your yard.

Keep It Clear

As a homeowner, you can reduce your worry and help ensure your side sewer line is kept clear and flowing by allowing only human waste, toilet paper, and drain water into the line. As a practice, don’t flush anything else down the toilet. This practice will help keep your side sewer in good condition and save you money.

To clarify the importance of this, take a moment to watch this informative video from the hard-working folks at Seattle Public Utilities. Also, see our post Don’t Flush So Called Flushables for a list of what should not be put down the toilet.


Because images of clogged side sewer lines are gross, we’ve attached a picture of our dog Bob instead.

At Raymark Plumbing & Sewer, we are happy to help with any of your side sewer or shared sewer line needs. We are the experts in resolving sewer problems and are a registered side sewer contractor. Call us at (206) 440-9077.

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