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Water & Sewer Utility
1 NW Martin Luther King Jr Blvd
Civic Center Complex, Room 104
Evansville, IN 47708
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Backup and Backflow

Sewer backups are a common problem in U.S. cities and towns.

Although municipal utility departments try to prevent such incidents, they still occur. The following information may help property owners and residents understand why backups happen, how they can be prevented and what steps citizens should take if a sewer backup affects their property.

What causes a sewer backup?

Sanitary sewers flow by gravity so they generally follow the natural slope of the ground. The sewer mains that the city owns and maintains are generally from eight to 15 feet deep, with some being much deeper. Sanitary sewer backups can be attributed to in either the city’s main sewer lines or in the private sewer service line, which the property owner owns and maintains (sewer line between buildings and the city’s main sewer line).

Causes of a backup may include pipe breaks or cracks due to tree roots, system deterioration, insufficient system capacity due to residential or commercial growth, or construction mishaps. In home and office plumbing systems, a frequent cause is accumulation of grease, tree roots, hair or other solid materials that are too large for wastewater pipes to handle.

Another frequent cause of blockages within the city’s system is vandalism. Report criminal activity by calling (812) 421-2130 to alert the sewer department and prevent backups from occurring.

How could a sewer backup affect me?

If the backup occurs in a city maintained line, the wastewater will normally overflow out of the lowest possible opening. In some homes - especially those with basements, or where the lowest level is even with the sewer lines - the overflowing wastewater may exit through the home’s lower drains and toilet.

What should I do if sewage backs up into my home?

First, take action to protect people and valuable property:

  • Keeping in mind that ceramic plumbing fixtures such as toilets are fragile, quickly close all drain openings with stoppers or plugs. Tub, sink and floor drains may need additional weight to keep them sealed.
  • Don't run any water down your drains until the blockage has been cleared.
  • Check with neighbors to determine if the backup appears to be in your neighbor's wastewater line, and/or widespread in your neighborhood. If it is, call (812) 421-2130.
  • Call a plumber if the problem is in your lateral service line.

If I call the city, what will they do about a sewer backup onto my property?

  • You will be asked questions about the backup timing, location, the property at risk, etc.
  • City personnel will check for blockages in the main line. If found, the blockage will be immediately cleared.
  • If the main line is not blocked, you will be advised to call a plumbing or sewer contractor to check your service line. Click here for the handbook on customer rights and responsibilities.
  • To minimize damage and negative health effects, you should arrange for clean up of the property as soon as possible. There are qualified businesses that specialize in this type of clean up and restoration.

How can I prevent sewer backups?

  • Avoid putting grease down your garbage disposal or household drain.
  • Never flush disposable diapers, sanitary napkins or paper towels down the toilet.
  • If the lateral line in your older home has a jointed pipe system, consider whether the roots of large shrubs or trees near the line could invade and break pipes. It is a good idea to know the location of your lateral line(s). You can call the sewer department for assistance in locating where your service line connects to the city’s sewer main. Your plumber may be able to help you further determine the service line location too.
  • If the lowest level of your home is below ground level, such as a basement floor drain, consider installing a backflow valve on the lowest drain(s). You may also use a plumbers test plug to close these drains when not in use.
  • For further information about preventive measures, contact a licensed plumber or visit your nearest plumbing supply dealer.

What does the municipality do to prevent this problem?

Reasonable effort by the City is undertaken to prevent backups in the public wastewater system before they occur:

  • Sewer lines are specially designed to prevent accumulation and stoppages.
  • In addition, we have maintenance crews that are devoted to inspecting and cleaning wastewater lines throughout the city on a regular schedule.
  • Degreasing chemicals are also injected into lines in areas that are prone to stoppages, such as those near restaurants, apartments or high-density housing developments.
  • Even with our maintenance schedule, however, backups are often beyond the city's control. Most that do occur are confined to the sewage pipeline, rather than backing up into a home.

Will insurance cover any damage to my home or property?

In the majority of cases, a special rider will need to be added to your homeowner’s or renter’s insurance policy to cover damages related to sewage backups or water damage. The city does not assume financial responsibility for damages resulting from sewage backups, since most stoppages are related to conditions that are beyond the city’s control.

How and where should I report a sewer backup?

Emergency crews are on call 24 hours a day, 7 days a week to assist you. In an emergency such as a sewer line backup, or if you observe any vandalism associated with the wastewater or sewer lines, contact Emergency Sewer Services at (812) 421-2130.