Seattle's Cleaning Threshold
Seattle Public Utilities states that businesses must clean interceptors according to manufacturer specifications. When specifications are unavailable, cleaning must occur before grease and food waste exceed 25 percent of interceptor capacity under Seattle Municipal Code 21.16.310.
Some businesses need weekly service, while others can operate longer between cleanings. The schedule must keep the interceptor functioning and below the governing buildup limit.
Build a Site-Specific Schedule
Start with conservative service, then record:
- FOG-layer thickness
- Settled-solids depth
- Total occupied percentage
- Meals or production volume
- Odor, slow-flow, or backup symptoms
- Cleaning and pumping dates
- Component damage or line restrictions
Shorten the interval when accumulation approaches the limit before the next planned visit.
Maintenance Records and Inspections
Keep invoices, pumping records, measured levels, dates, service-provider information, and corrective work available. Records help demonstrate routine maintenance and support schedule changes.
Regulators may set a specific periodicity for an establishment. Follow written agency instructions when they are more restrictive than the general plan.
Frequently Asked Questions
Does Seattle require monthly pumping?
Seattle's public guidance does not impose one universal monthly interval. Manufacturer specifications, the 25-percent threshold, and facility-specific direction govern frequency.
Can kitchen practices extend the interval?
They can reduce accumulation, but measured buildup must still remain within requirements.
Schedule Compliance-Focused Service
Schedule Grease Trap Pumping Schedule Requirements support with Seattle Plumbers for measured buildup, documented maintenance, and a defensible service interval. Confirm current requirements with Seattle Public Utilities for your facility.