Frequently Asked Questions

Sewer Backup? Call us FIRST at: (513) 352-4900

Q:  Why does my property have sewer backups when it rains?

A:  Sewer backups (SBUs) have several causes.

One possible cause of SBU is inadequate capacity of public sewer pipes.  On a typical, dry-weather day, wastewater flows from building sewers into MSD‘s public sewers without any problems.  The public sewer system then carries the wastewater to a treatment plant, where it is cleaned and released into the environment.  However, when it rains, some parts of the sewer system carry large amounts of rainwater in addition to wastewater.

If the combined amount of rainwater and wastewater is more than the pipes can carry, some of the water stops flowing forward and can actually back up in the sewer pipes.  Excess water may get pushed out of the sewer pipe, overflowing from manholes or through private building sewer pipes. 

Another possible cause of SBU is problems with the plumbing system within a building.  In fact, this is the most common cause of SBU for MSD’s customers.  More than 90% of SBUs reported to MSD turn out to be problems such as:

  • Clogs or breaks caused by tree or plant roots that have grown into the building sewer pipe on your property.
  • Clogs resulting from materials flushed into sinks or toilets that do not dissolve in water, like grease or baby wipes.
  • Clogs resulting from debris from gutters and downspouts that flows directly into the private building sewer pipe.

For more information on these problems and how to fix them, check the Resources section of this site.

Q: Why do roots get into the sewer pipes?

A: Trees and shrubs will always grow their roots towards sources of water and nutrients.  Sewer systems provide them with a generous supply of the water and nutrients they are seeking.  A tree root often gets into a pipe at a crack or joint in the pipe.  Once it gets in there, it will grow and increase in size, which can lead to blockage and breakage of the pipe.

It’s possible to control or eliminate roots in the sewer pipes through periodic root cutting, some chemical treatments, pipe replacement and pipe lining. Removing trees and shrubs near the sewer lines on your property can help, although it takes several years for the root system to stop growing.

Q: How do i know if a backup is coming from the public sewer or if it is coming from something inside my building?

A: Sometimes, it is hard to tell where an SBU is coming from.  Most often we see SBUs come from a basement floor drain.  Other lower level plumbing fixtures, such as toilets, showers or sinks in the basement may have backups.  If basement fixtures are not backed up, but drains on upper levels are backed up, the cause is very likely to be a building plumbing problem.

If the backup is coming from the basement floor drain or fixtures, it may be caused by a problem in the public sewer system. In this case, please report it to MSD.  You can report it by phone at (513) 352-4900, or you can submit an online report by clicking here. We are available to receive SBU reports 24 hours a day, 7 days a week.  

Q. What is the difference between a “private building sewer” and a “main sewer” or “public sewer?”

A: The “Building Sewer” is the privately-owned sewer pipe that takes the wastewater of a home or building and conveys it to the main public sewer.  The owner of the building is the owner of the building sewer.  The “Main Public Sewer” is the publicly-owned pipe that collects the wastewater from many buildings and carries it to a wastewater treatment plant for removal of wastes.  The treatment plant returns the clean water to the environment.

The building sewer usually is located mostly within the boundaries of private property.  The end of the pipe, where it connects to the public sewer, is often located within the public right-of-way (under the street pavement or in an easement).  But it is important to understand that the building owner is owner of the entire building sewer pipe, even the portion of the pipe that is under the street. 

Q. Who is responsible for sewers that are blocked or clogged up?

A. When the main public sewer is blocked or clogged up, MSD is responsible for clearing the obstruction.  When a building sewer pipe is blocked or clogged up, the building’s owner is responsible for clearing the obstruction.

Q. Who is responsible for repairing sewers that are broken or collapsed?

A. When the main public sewer is broken or collapsed, MSD is responsible for fixing the pipe.  When a building sewer pipe is broken or collapsed, the responsibility for fixing the pipe depends upon the location of the breakdown.  If the building sewer is broken within the boundaries of the property, the owner must have the pipe repaired.  If the building sewer is broken within the public right-of-way, MSD takes responsibility for fixing the pipe. 

Q: If the building sewer in the street is private, why does MSD dig up the street and repair it?

A: MSD does this kind of repair for safety reasons. It can be very difficult to make building sewer repairs under street pavement, and many times there are water lines or gas mains nearby.  MSD has the training, staff, and equipment to quickly mobilize a repair crew, get the needed permits, and manage the traffic and other utilities. 

Q: What is a sanitary sewer?

A: A sanitary sewer is intended and designed to transport sanitary sewage (wastewater from your drains and toilets) to a wastewater treatment plant for treatment.

Q: What is a combined sewer?

A: A combined sewer is a sewer intended and designed to carry sanitary sewage (wastewater from your drains and toilets) in dry weather, and a combination of sanitary sewage and stormwater during wet weather.  Combined sewers convey wastewater and stormwater to a treatment plant for treatment.

  • Contact the SBU Program

    Report a sewer backup

    Phone: (513) 352-4900
    Online: Report a sewer backup online

    If you have a sewer backup (SBU), please report it immediately. You can report sewer backups 24 hours a day, 7 days a week.
    Note: SBUs must be reported within 24 hours to be eligible for reimbursement of damages.

    Get information about sewer backup prevention

    (513) 352-4288

    Filing a claim

    Start here: How to File a Claim
    Get help filing a claim: (513) 244-5100
    Just need the form? SBU Claim Form (pdf)

    SBU Ombudsman with the Legal Aid Society of Greater Cincinnati

    (513) 362-2801

SBU Site Search:

MSD Home    Customer Service    City of Cincinnati    Hamilton County    Project Groundwork

Understanding Sewer Backups

How to Prevent a Sewer Backup