Sanitary Sewer Overflow/Bypass/Backup Notification

The owner or operator of a sanitary sewer must notify MassDEP, and other state and federal entities as necessary, of all sewer overflows and bypasses, per 314 CMR 12.00, "Operation, Maintenance and Pretreatment Standards for Wastewater Treatment Works".
In the event of an overflow or bypass, this notification must be filed within 24 hours.

MassDEP Sanitary Sewer Overflow/Bypass Notification

Sanitary Sewer Overflow/Bypass Contact Information-US EPA

The Details of Sanitary Sewer Overflow/Bypass/Backup Notification

What you need for Sanitary Sewer Overflow/Bypass/Backup Notification

In the event of an overflow or bypass of a sanitary sewer, the owner or operator of the involved facility must notify MassDEP, and other state and federal entities as necessary, within 24 hours. This applies to: 

  • Municipal, state, federal, regional, industrial or other private wastewater collection system;
  • Wastewater utility;
  • Wastewater treatment works;
  • Facility with a groundwater discharge permit;
  • Facility with a surface water discharge permit.

This requirement includes any owner or operator of a satellite municipal collection system or other collection system that is part of a larger POTW not under the same ownership and control.

The following situations require notification to DEP and submittal of the SSO Report Form:

  • An un-permitted overflow or bypass;
  • Backup of wastewater into public or private property when the event is caused by a condition of the system owned and operated by the sewer authority
  • In a combined sewer system, an overflow or bypass during dry weather conditions or at a location not covered by a NPDES permit, or from a portion of the system that has a separate sanitary sewer.

Backups of wastewater into a property which are not caused by conditions in the system owned and operated by the sewer system are not required to be reported. These incidents normally occur due to blockages in service connections to a property or blockages in the internal plumbing system.

How to report Sanitary Sewer Overflow/Bypass/Backup Notification

Immediately after discovering the overflow or bypass, notify MassDEP, US EPA, and other parties by telephone and/or email. See the Instructions below for the list of agencies and contact numbers.

Using the Sanitary Sewer Overflow/Bypass Notification form below, submit a written report to MassDEP within 5 calendar days of the time you became aware of the incident. See the Instructions below for more details.

Next steps for Sanitary Sewer Overflow/Bypass/Backup Notification

  1. Review the Instructions

    Guidance on how to prepare your report and contact information for agencies which must be notified in the event of a sewer overflow or bypass. 

  2. Complete the Notification Form

    This form must be completed and submitted within 5 calendar days of the time you become aware of the incident. 

  3. Submit Your Notification Form

    Email the Notification Form to the attention of the Bureau of Water Resources in your DEP regional office and to the appropriate EPA personnel depending on your DEP region (see lists below).

Contact for Sanitary Sewer Overflow/Bypass/Backup Notification

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