City of Phoenix Water Services — Environmental Services Division (FOG)
Not legal advice. Last verified 2026-09-22 · confidence high. Confirm with the city before you set a contract.
Minimum interval: 30 days.
Accumulation rule: Most interceptors stop working effectively when FOG and solids reach 25% of capacity; if greater than 25%, a full cleaning is required. Hydromechanical (indoor traps, typically ≤4 fixtures): fully pump every 30 days; no hydromechanical unit may go more than 90 days without maintenance unless the Director grants a variance. Gravity interceptors at food service establishments that capture FOG: fully pump at least once every 3 months unless a Director variance. New facilities should monitor accumulation and pump sooner if needed. Full pump-out by a licensed pumper; interceptor left empty; no reintroduction of water; enzymes/emulsifiers prohibited.
Records: keep required records about 3 years on site.
Hauler: Licensed pumper. FOG mat, liquids, sludge, and scrapings go to a licensed waste disposal facility.
Permit: All Phoenix FSEs that prepare food must have a grease interceptor. Hydro for up to four fixtures without a disposer or dishwasher; gravity required if a disposer, dishwasher, or more than four fixtures. Interceptor installs go through Planning and Development plan review.
Enforcement: Inspectors can require clean/replace/repair with a deadline. Confirm current penalty amounts with Phoenix Environmental Services. City Code Chapter 28 is the underlying ordinance (cited in the June 2024 BMP).
NFPA 96 frequencies (widely republished by fire departments): solid fuel monthly; high-volume quarterly; moderate semiannual; low-volume annual. Insurers and local fire inspectors can be stricter.