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Municipal Code

It's the Law

Fats, oils, and grease are prohibited discharges.

  • Seattle Municipal Code prohibits the discharge of wastewater containing more than 100 parts per million by weight of fats, oil, or grease ( SMC 21.16.300 A. 2).
  • A business is in violation if there is a visually evident accumulation of grease originating in the private sewer system ( SMC 21.16.300 B).
  • Pretreatment devices such as grease traps and grease interceptors must be installed and maintained to intercept grease and oil before it is discharged to the public sewer system ( SMC 21.16.310 A).
  • Pretreatment devices must be cleaned when 25% of their volume is occupied by accumulated grease and food waste. ( SMC 21.16.310 B).

Changes to Seattle’s Municipal Code

  • Seattle’s Municipal Code
    Since 1968, Seattle Municipal Code has prohibited the discharge of waste water containing more than one hundred parts per million by weight of fat, oil or grease, and has also required private pretreatment facilities to intercept grease to be maintained in continuously efficient operation at all times.
  • 25% rule
    Beginning January 19, 2011, SMC 21.16.310 specifies the 25% rule as the standard to determine if a pretreatment facility to intercept grease is in continuously efficient operation. While this is a change in code language, SPU has been using the 25% rule as the inspection standard for continuously efficient operation for many years. Food Service Establishments must maintain (clean out) their grease trap or interceptor when 25% or more of the volume is filled by food and grease.
  • No additives in pretreatment devices
    SMC 21.16.310 now prohibits the use of emulsifying agents, enzymes, bio-additives, or similar chemicals in pretreatment devices.
  • Varied penalty fees
    Enforcement provisions for discharges of F.O.G. to the sewer system will vary to better match the size of the penalty to the degree of violation. Penalty fees range from $250 - $5,000.