For restaurant owners in Los Angeles County, the “FOG” (Fats, Oils, and Grease) program isn’t a suggestion—it’s the law.
Grease blockages cause 47% of all sewer overflows in the county. To combat this, strict regulations are enforced on all food service establishments. Failing to maintain your grease trap doesn’t just risk a plumbing backup during the dinner rush; it risks massive fines from the city.
The 25% Rule
The Golden Rule of grease traps in LA County is the 25% Rule.
Your grease trap or interceptor must be cleaned *before* the combined layer of floating grease and settled solids reaches 25% of the tank’s total liquid depth.
Once the trap is more than 25% full, it stops separating grease effectively. Grease starts escaping into the city sewer, which is exactly what inspectors test for.
How Often Should You Clean It?
There is no “one size fits all” schedule, but generally:
- Small indoor traps (under sink): Weekly or Bi-weekly.
- Large outdoor interceptors (750+ gallons): Quarterly (every 3 months) is the standard minimum, but high-volume kitchens may need monthly service.
Documentation is Key
The city doesn’t just take your word for it. You must keep a maintenance log on-site for at least 3 years. This log must show dates of cleaning and the volume removed. If an inspector walks in and you can’t produce the log, you can be fined immediately.
Odor Control
Beyond compliance, a dirty grease trap smells horrific. The decomposing food waste creates sulfuric gases that can drift into your dining room or kitchen, turning customers away. Regular hydro jetting of the inlet and outlet lines during cleaning helps minimize these odors.
Partner with a Pro
Western Rooter provides compliant grease trap maintenance for restaurants across the San Gabriel Valley. We handle the pumping, the cleaning, and the paperwork. Contact our commercial team to set up a worry-free maintenance schedule.
