Reviewed August 16, 2026. If wastewater or sewage is backing up into a food establishment, treat it as a possible imminent health hazard. Stop affected operations, protect people and food from exposure, and follow the local health and wastewater authorities’ instructions.
This is a response framework, not permission for restaurant staff to clean, open, pump, snake, vacuum, or repair an interceptor or contaminated drainage system.
Immediate response
- Stop using affected fixtures and equipment. This may include sinks, dishwashers, food-preparation equipment, or other fixtures discharging to the affected line. Use site-specific shutoffs only when staff are trained and it is safe.
- Isolate the area. Keep employees, customers, food, utensils, and clean equipment away from wastewater. Prevent material from reaching storm drains or unaffected areas.
- Call qualified service. Describe whether the incident involves slow drainage, an indoor backup, an interceptor overflow, several fixtures, or a suspected line problem.
- Notify the correct authority. Contact the local health department, wastewater or pretreatment program, stormwater authority, or other contact required by the facility’s rules and permits.
- Document only when safe. Record the discovery time, location, visible extent, affected fixtures, calls made, actions taken, and service records. Do not enter the contaminated area merely to take photographs.
FDA’s Food Code treats sewage backup as an event that may create an imminent health hazard and distinguishes unaffected areas, but it is a model code. The local authority decides whether any part of the establishment may operate and what approval is needed before reopening.
What not to do
- Do not hose wastewater, grease, or cleanup material toward a gutter, storm drain, sidewalk, or another drain.
- Do not add drain cleaners, degreasers, enzymes, bacteria, or other chemicals as an emergency fix.
- Do not ask untrained staff to open the interceptor, reach into it, remove parts, pump it, vacuum wastewater, or clear a line.
- Do not enter a tank, vault, or other confined space. OSHA identifies possible toxic or flammable gas, fall, engulfment, and confined-space hazards.
- Do not restart affected food work based only on the fact that water appears to drain again.
After the immediate problem is controlled
Obtain the service record or manifest required by the local FOG program, permit, or contract. Ask the provider to document the observed cause, work completed, removed material, disposal information, equipment condition, and any recommended follow-up.
Follow the local health authority’s cleanup, sanitation, food-disposal, and reopening directions. Official emergency plans may require professional cleanup, disposal of contaminated porous materials, cleaning and sanitizing affected surfaces, and an inspection or authorization before resuming operations.
Review the incident with the facility manager. Recurrence can justify assessment of the interceptor, internal plumbing, downstream line, service history, kitchen practices, and the local maintenance or sizing requirements. Do not assume every backup was caused by a trap exceeding a universal percentage.
Build a site-specific response plan
Keep current provider and authority contacts, safe fixture-shutoff instructions, the interceptor location, access information, service records, and manager responsibilities in an accessible plan. The incident readiness checklist explains what to prepare without creating a do-it-yourself cleanup kit.
Frequently asked questions
Is every grease trap odor an emergency?
No. Odor has several possible causes and is not a diagnosis. Strong odor with dizziness, eye or breathing irritation, an overflow, or a sewage backup requires people to leave the affected area and obtain urgent qualified help.
Should staff shut off all water?
Stop using fixtures and equipment connected to the affected line. Use only the facility’s approved, site-specific shutoff procedure when trained staff can do so safely.
Who decides when the kitchen can reopen?
The controlling local health authority and the facility’s adopted emergency plan determine closure, cleanup, inspection, and reopening requirements.
Does an emergency always require a pump-out?
No single treatment fits every cause. A qualified provider should determine whether pumping, plumbing repair, line work, equipment repair, or another response is required.
Official sources
- U.S. FDA: 2022 Food Code
- Oregon Health Authority: Emergency Handbook for Food Managers
- OSHA: Grease Trap Hazards
- City of Portland: FOG and storm-drain best management practices
Author: Grease Trap Locator Editorial Team
The Grease Trap Locator editorial team covers FOG compliance, grease trap maintenance, and commercial kitchen regulations across the US and Canada. Our guides are written for restaurant owners, facility managers, and food service operators who need practical, accurate information without the fluff.
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