Sewer Backups

What To Do

The flowchart below can be followed to help property owners and residents navigate through a sanitary sewer backup. We know this is a stressful event, and the City's engineering department is here to help.

flowchart of what to do for a sewer backup issue

Notify the Milwaukee Metropolitan Sewerage District and the City of West Allis of any backups on residential property.

If there is water in the basement, let the City know by completing the wet basement form.

Sewer Laterals

The plumbing inside homes are connected to the City's sanitary sewer through an underground pipe called a sanitary lateral. Property owners own this pipe from inside of the house to the connection point of the City's sewer in the road and are responsible for keeping it properly flowing and free from cracks, holes, and other defects. 

While the property owner is responsible for their private sanitary lateral, the sanitary sewer in the roadway is maintained and owned by the City. The diagram below helps show this distinction.

diagram of Public sanitary sewer

What to Flush

A friendly reminder from the Engineering Department that just because something can be flushed doesn't mean it should be.

Paper towels, napkins, "flushable" wipes, and many other personal hygiene products do not disintegrate like toilet paper. Flushing these items can create clogs in pipes and the community's sewer pipes.

More information about what should and shouldn't go down the toilet can be found by watching the videos below or by visiting the What Not to Flush Down the Toilet.

Prevent Sewer Backups

Backups can be an unpleasant and usually costly experience. To reduce the risk of experiencing a backup:

  • Televise your sanitary lateral.

    This is the best way to determine the condition of your entire lateral.

    Inspection can reveal cracks, breaks, joint problems, and/or root intrusion.

  • Use root treatment products.

    Tree roots are able to find their way into your lateral through cracks.

    Left over time, these roots block solids and can cause a build up of sewage.

    Products can be purchased at most hardware and home improvement stores. Hire a pipe cleaning specialist or a plumber to remove the roots completely if necessary.

  • Avoid pouring fats, oil, or grease down the drain.

    Do not dispose of coffee grounds or other heavy solids down the drain.

    Pour into a coffee can or similar container, allow them to cool and solidify, and then deposit in the trash.

  • Only flush the three p's - pee, poop, and toilet paper. Do not flush wipes, diapers, or feminine hygiene products, even if they are labeled "flushable." So-called flushable products catch on lateral obstructions such as roots or grease, and form clogs.

Additional Information

Learn more about your sanitary lateral.

More information regarding the hazards that are created with a basement backup can be found on the Water in my Basement webpage.