Unusual Discharge

 An Unusual Discharge (UD) is a discharge to the City sewer system that meets any of the following criteria:

                (1) Discharge is through a non-permanent entry point into the sewer system

                (2) Discharge is not the result of a normal business operation

                (3) Discharge is a one-time special discharge.

 Per TMC 930.08, any person seeking to release an unusual discharge to the city sanitary sewer system shall submit an application and pay an application fee to the Division of Environmental Services. Sampling analytical from the requested discharge must also be submitted with the application. The analytical shall not exceed the concentrations listed in TMC, Appendix A.


If the UD application is approved:

  • The User shall be issued a discharge permit after paying a permit fee to the Division of Environmental Services based upon the volume of flow as stated in Appendix A. 
  • The User shall make arrangements with the Division of Environmental Services or the Division of Sewers & Drainage to determine an acceptable discharge point to the sanitary sewer system.
  • A flow meter or other method acceptable to the Division of Environmental Services must be used to determine the amount of waste discharge to the sewer system. If the User is unable to obtain a meter, the City will use the full capacity of the containment device used to hold the wastewater prior to discharge for billing purposes.


In addition to the application and permit fees, the User shall also pay the charges specified in TMC 929.03 (c), also known as surcharges.

Click here for the Application for Unusal Discharge Form