Sewer backups can be messy, expensive and inconvenient; however, City Engineering is here to help you through the process.

A sewer backup is a blockage in the private sewer lateral or the city main that does not allow sewage to flow down the pipes properly.

When this happens it can cause sewage to pool or flow back into a home. It usually will pool up around a floor drain, toilet or shower that is on the lowest level of the home (basement for instance).

A sanitary sewer overflow occurs when a city main becomes plugged from debris or collapses, which does not allow sewage to flow. The sewage then starts to fill up the sewer mains and structures up stream. If the sewage gets high enough it will start to drain out of sanitary access structures that are located in the street or terrace. This is called a sanitary sewer overflow (SSO).

Sanitary Sewer Overflow Example
Example of a sanitary sewer overflow

Sewage is any kind of contaminated water that needs to be treated by the Nine Springs Wastewater Treatment Plant, 1610 Moorland Rd., owned and operated by Madison Metropolitan Sewer District (MMSD). This includes, but not limited to, toilet, sink, shower, dishwasher or washing machine water.

One thing that should not be considered sewage is basement drain tile sump pump for ground water. These are NOT to be pumped into a floor drain or sink or plumbed into the home sewer drainage system. This is considered clear water and needs to be pumped outside onto the lawn or connected to the city storm sewer system.

How to Report a Sewer Backup

  1. Call Engineering

    Homeowners should call the 24/7 Engineering Operations Line at 608-266-4430 if you suspect a sewer backup. Normal hours are Monday-Friday, 6:30 a.m.-4:30 p.m.  Outside of normal hours, the Emergency Water Dispatch will receive the call and alert Engineering to dispatch a crew to clean the sewer. Our crews are available 24 hours a day.

  2. Stop Use

    Homeowners should stop all water use in the home.

  3. Call Your Insurance Company

    Call your insurance company if you have homeowners insurance with a policy for backup or service line warranty protection (sewer lateral insurance). Please stay out of the standing water so not to contaminate other parts of their home.  

  4. Wait and Observe

    Homeowners should wait for the City crew to respond and figure out if it is the main or lateral issue. The way to identify whether it is a sewer main issue or a lateral issued is to observe what happens to the backed up wastewater after the City cleans the sewer main.

Emergency Crew Process

City crews check the public sewer main first. If the public main is blocked, the crew will remove the obstruction to restore service. The crew will notify the property owner or resident when the service has been restored. Sewage should flow back down the floor drain after City crews clean the City sewer main. If it is a lateral issue, the water will remain after City crews clean the sewer main. The emergency crew will immediately notify the property owner or resident whether it is a problem with the sewer main or lateral.

How to Respond to a Private Sewer Lateral Issue

Clean your lateral

If a blockage is in the private building sewer, it is the responsibility of the property owner to clear the blockage. There are various private firms listed under "sewer cleaners" in the yellow pages who remove the blockage from the private building sewer.

If it is a lateral issue, homeowners will need to call a rooter or plumbing service or else rent equipment to attempt to remove the blockage themselves. If it is a problem with your lateral and it is recurring, homeowners may want to have their lateral televised (CCTV). The City recommends homeowners to always get a copy of the video for their records.  When backups are reported, the City main will be cleaned regardless of whether the problem is related to the sewer lateral or the City sewer main. This is City protocol on all sewer backup calls.

In the event that cleaning the lateral is not successful in removing the blockage from the private building sewer, it is possible that the private building sewer has collapsed. The property owner or resident is urged to again contact City Engineering Division's Sewer Maintenance Section to determine what further measures may be undertaken to re-establish sewer service. In some instances the entire sewer lateral within the right-of-way may have to be replaced.  The owner is responsible for contracting with a contractor who is prequalified by the City to make the repair(s).

Clean Up

Home Owners are responsible for any clean up on their property. Engineering Operations Crews will not enter the home to assist in any clean up. Homeowner’s can file a claim with the City for a sewer backup.  To file a claim against the City, contact City Risk Management.

Repair Lateral

If the sewer lateral is broken and a repair is necessary, homeowners will need to complete a repair to the lateral.  Sewer laterals repair are not completed by crews or paid for by Engineering. Work behind the property can be completed by a homeowner or a plumber hired by the homeowner.  The City requires contractors to be licensed and prequalified to work in the City public right-of-way. Engineering does have a Lateral Restoration Financial Assistance Program to assist with the pavement restoration if you home is located on a busy or newer street and your property is located in the City of Madison.

The Engineering Division recommends property owners require contractors to televise the sewer lateral and provide a video before agreeing to have the lateral repaired or replaced. Videos will indicate is the problem is an isolated repair or if a full lateral replacement is necessary. Engineering staff is available to review the lateral video free of charge.

Backup Causes

  • Tree Roots

    Tree roots can enter the service pipe at joints and travel a long way, causing blockages along the way. Tree roots can also create structure defects when they crack and break pipes as they grow.

  • Fats, Oils and Grease

    Blockage can happen when homeowners do not pay attention to what goes down the drain such as: grease, hair, dirt or solid materials such as disposable diapers, sanitary napkins, broken dish ware, garbage and debris. Learn more about impacts of FOG.

  • Aging

    Structural defects happen as systems age and deteriorate. These defects include partial or full pipe collapse, cracks, holes and fractures.  City sewers lifespan is 100 years. Your sewer lateral age is most likely the age of your home.

Please call Engineering Operations 608-266-4430 24/7 if you suspect a sanitary sewer overflow.