What Causes Sewer Backups?

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

On a typical dry weather day, wastewater from homes, schools and businesses flows through the Metropolitan Sewer District's public sewers without problem.  

However, during wet weather, 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, the water stops flowing forward and begins to back up. Excess water may get pushed out of the pipe through manhole lids and through private building sewer pipes (sometimes called a "sewer lateral" or "house tap") that connect buildings to the sewer system.

When this happens, basements and lower levels can get flooded with the sewage/rainwater mixture.

Click to learn more about building sewers.

  • Contact the SBU Program

    Report a sewer backup

    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.

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

    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:

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Understanding Sewer Backups

How to Prevent a Sewer Backup