FOG Compliance for Restaurants: A Complete Guide to Fats, Oils & Grease Regulations

If you operate a commercial kitchen, FOG compliance isn't optional — it's the law. And the consequences of ignoring it range from hefty fines to kitchen shutdowns, sewer backups, and even lawsuits.

But navigating FOG regulations can be confusing. Requirements vary by city, county, and state. Inspectors show up unannounced. Record-keeping rules are detailed and specific. And a single violation can cost your business thousands of dollars.

This guide breaks down everything restaurant owners, kitchen managers, and food service operators need to know about FOG compliance — from the basics of what FOG is to how to handle a violation if you receive one.

What Is FOG and Why Is It Regulated?

FOG stands for Fats, Oils, and Grease — the byproducts of cooking that wash off plates, pans, and equipment and flow into your drainage system. FOG comes from cooking oils, butter, lard, meat drippings, dairy products, sauces, dressings, and food scraps.

When FOG enters the sewer system, it cools, solidifies, and clings to pipe walls. Over time, these deposits build up and form blockages called fatbergs — massive clogs of hardened grease mixed with other debris. A single restaurant can send hundreds of gallons of FOG into the sewer system each year if left unmanaged.

The consequences are serious:

• Sanitary sewer overflows (SSOs): Blocked pipes cause raw sewage to back up into streets, basements, and waterways. The EPA estimates that grease causes approximately 47% of all sewer blockages in the United States.
• Environmental contamination: Sewage overflows pollute rivers, lakes, and coastal waters, harming ecosystems and creating public health hazards.
• Costly infrastructure damage: Municipalities spend billions annually repairing grease-damaged sewer lines, and those costs get passed along through higher utility rates.

This is why virtually every municipality in the country requires commercial food service establishments to manage their FOG discharge — and why violations carry steep penalties.

Federal vs. State vs. Local Regulations

FOG regulation in the United States operates on three levels, and understanding who enforces what is critical for staying compliant.

Federal Level: The Clean Water Act

The Clean Water Act (CWA) is the foundational federal law that governs water pollution. It prohibits the discharge of pollutants — including fats, oils, and grease — into navigable waters without a permit. The EPA sets the broad framework, but delegates most enforcement authority to states and local municipalities.

The EPA's National Pretreatment Program requires publicly owned treatment works (POTWs) to regulate what flows into their sewer systems. This is the legal basis for local FOG programs — your city's wastewater authority is required to prevent grease from damaging its infrastructure.

State Level

Each state sets its own environmental and plumbing codes that dictate grease trap and interceptor requirements. Some states have statewide FOG programs with uniform rules, while others delegate everything to local jurisdictions. For a detailed breakdown of your state's specific requirements, see our state-by-state compliance guide.

Local Level

This is where most FOG enforcement actually happens. Your city or county wastewater authority typically runs the local FOG program, which sets specific rules for:

• What type and size of grease trap or interceptor you need
• How often it must be cleaned
• What records you must keep and for how long
• Inspection schedules and right-of-entry requirements
• Fines and enforcement actions for violations

The bottom line: Your local FOG ordinance is the one you'll deal with day-to-day. Contact your local wastewater authority or public works department to get a copy of the specific regulations that apply to your establishment.

Common FOG Program Requirements

While specific rules vary by jurisdiction, most FOG programs share these core requirements:

1. Grease Trap or Interceptor Installation

Nearly every municipality requires commercial kitchens to install a grease trap (smaller, typically indoor units) or a grease interceptor (larger, typically buried outdoor units). The required size depends on your kitchen's flow rate, number of fixtures connected, and local plumbing codes.

Most jurisdictions follow the Uniform Plumbing Code (UPC) or International Plumbing Code (IPC) for sizing calculations. New construction or major renovations typically trigger mandatory installation, but many FOG programs also require retrofitting existing kitchens.

2. Regular Cleaning and Pumping

Grease traps and interceptors must be cleaned on a regular schedule. Most jurisdictions require cleaning at minimum every 90 days, though high-volume kitchens may need monthly service. Many local programs tie the cleaning requirement to the 25% rule (explained below).

3. Manifest and Record Keeping

Every time your grease trap is cleaned, the hauling company must provide a waste manifest — a document recording what was removed, how much, and where it was taken for disposal. You are required to keep these manifests on file, typically for 3 to 5 years, depending on your jurisdiction.

4. Best Management Practices (BMPs)

Most FOG programs require you to implement BMPs in your kitchen, including:

• Dry-wiping pots, pans, and dishes before washing
• Using drain screens or strainers on all sinks
• Properly storing and recycling used cooking oil
• Training employees on FOG disposal procedures
• Posting "No Grease" signage near sinks

5. Inspections

Your local FOG program has the authority to inspect your grease trap and review your records — often without advance notice. Inspections may be routine (scheduled annually or semi-annually) or triggered by a complaint, sewer blockage, or previous violation.

The 25% Rule Explained

The 25% rule (also called the one-quarter rule) is the industry-standard threshold for when a grease trap must be cleaned. Here's how it works:

If the combined depth of floating grease (FOG layer on top) and settled solids (food particles on the bottom) reaches 25% of the trap's total liquid depth, the trap must be pumped immediately — regardless of your scheduled cleaning date.

For example, if your grease trap has a liquid depth of 24 inches, the trap needs cleaning when the FOG and solids layers together reach 6 inches or more.

Many municipalities have codified this rule into their local FOG ordinances, meaning exceeding the 25% threshold is itself a violation — even if you're technically within your scheduled cleaning window. This is why regular self-monitoring between scheduled pump-outs is essential. Checking your trap weekly with a measuring rod takes less than five minutes and can save you from a surprise violation.

How FOG Inspections Work

Knowing what inspectors look for can help you stay prepared. Here's what typically happens during a FOG inspection:

What Inspectors Check

• Grease trap condition: Is the trap structurally sound? Is the lid secure? Are baffles intact and in the correct position?
• FOG and solids levels: Inspectors measure the depth of grease and solids to determine if you're within the 25% threshold.
• Cleaning records: They'll ask to see your waste manifests, cleaning logs, and service receipts. Missing or incomplete records are one of the most common violations.
• Best management practices: Are drain screens installed? Is used cooking oil stored properly? Are employees trained?
• Plumbing connections: All grease-producing fixtures (three-compartment sinks, pre-rinse sinks, dishwashers) must be connected to the grease trap. Floor drains in food prep areas should also be connected.
• Additives and enzymes: Many jurisdictions prohibit the use of chemical additives, emulsifiers, or enzyme treatments in grease traps. These products can break up grease temporarily, allowing it to pass through the trap and re-solidify downstream in the sewer.

Types of Inspections

• Routine inspections: Scheduled annually or semi-annually as part of the local FOG program.
• Complaint-driven inspections: Triggered by neighbor complaints, odor reports, or a nearby sewer blockage.
• Follow-up inspections: After a violation, inspectors will return to verify you've corrected the issue.
• Pre-opening inspections: New restaurants or renovated kitchens are inspected before they can begin operating.

Fines and Penalties for FOG Violations

FOG violations carry real financial consequences. Penalties vary widely by jurisdiction, but here are specific examples from around the country:

Beyond direct fines, violations can trigger:

• Mandatory corrective action orders requiring you to install, upgrade, or repair equipment at your own expense
• Increased inspection frequency and monitoring requirements
• Sewer surcharges for excessive FOG discharge
• Liability for cleanup costs if your FOG causes a sewer blockage or overflow
• License revocation or suspension of your food service permit in extreme cases

To understand the full consequences of neglecting your grease trap, read our article on what happens if you don't clean your grease trap.

How to Stay Compliant: Your FOG Compliance Checklist

Use this checklist to ensure your establishment meets FOG requirements:

1. Obtain your local FOG ordinance. Contact your city or county wastewater department and get a copy of the specific regulations that apply to your business.
2. Verify your grease trap is properly sized and installed. Confirm it meets local plumbing code requirements for your kitchen's flow rate and fixture count.
3. Establish a cleaning schedule. At minimum, clean every 90 days — more frequently if your kitchen produces high volumes of grease. Never let FOG and solids exceed the 25% threshold.
4. Hire a licensed hauler. Use only licensed, permitted grease trap cleaning companies. Verify they provide proper waste manifests and dispose of waste at approved facilities. Find licensed companies near you.
5. Implement best management practices. Train staff on proper FOG disposal, install drain screens, use grease-collection containers, and post signage.
6. Maintain complete records. Keep all waste manifests, cleaning logs, inspection reports, and maintenance records organized and accessible for the required retention period.
7. Self-monitor regularly. Check your grease trap weekly to gauge FOG and solids levels. Keep a log of your observations.
8. Stay current on regulation changes. Local FOG ordinances are updated periodically. Stay subscribed to your wastewater authority's communications.
9. Respond to violations promptly. If you receive a notice of violation, act immediately — delays result in escalating penalties.

Record Keeping Best Practices

Good records are your best defense during an inspection — and your strongest evidence if you ever need to dispute a violation. Here's what you should keep and how to organize it:

Waste Manifests

Every grease trap pump-out should generate a manifest that includes:

• Date and time of service
• Name and permit number of the hauling company
• Volume of waste removed (in gallons)
• Type of waste (FOG, solids, wastewater)
• Disposal facility name and location
• Signatures of both the hauler and your representative

Keep original manifests for the duration required by your local ordinance — typically 3 to 5 years. Make digital copies as backup.

Cleaning Logs

Maintain a dedicated cleaning log that records:

• Date of each cleaning
• Company that performed the service
• Condition of the trap before and after cleaning
• Any repairs or issues noted
• Next scheduled cleaning date

Self-Monitoring Logs

Record your weekly grease trap checks, including:

• Date and time of check
• Estimated FOG layer depth
• Estimated solids layer depth
• Combined percentage of trap capacity
• Name of person who performed the check

Inspection Reports

Keep copies of all inspection reports from your local FOG program, including any notices, warnings, or violation letters. Document any corrective actions you take in response.

Pro tip: Keep all your FOG compliance records in one binder or folder — physical or digital — that any manager can access immediately. When an inspector shows up unannounced, you want to hand over a complete, organized set of records without scrambling.

What to Do If You Get a FOG Violation

Receiving a violation notice is stressful, but how you respond determines whether the situation stays manageable or spirals into something much worse.

1. Read the notice carefully. Understand exactly what the violation is for, what corrective action is required, and the deadline for compliance.
2. Act immediately. If the violation is for an overdue cleaning, schedule one right away. If your records are incomplete, gather and organize them. The faster you correct the issue, the better your position.
3. Document your corrective action. Take photos, save receipts, and keep written records of every step you take to resolve the violation. You'll need this evidence for the follow-up inspection.
4. Contact the issuing authority. If you believe the violation was issued in error, or if you need an extension on the compliance deadline, contact the inspector or the FOG program coordinator directly. Most regulators prefer working with cooperative businesses over escalating enforcement.
5. Schedule your follow-up. Many violations require proof of correction within a specific timeframe — 30 days is common. Make sure you meet that deadline.
6. Prevent repeat violations. Use the violation as a catalyst to review and strengthen your entire FOG compliance program. Repeat offenders face dramatically higher fines and increased regulatory scrutiny.

If you've been operating without a proper grease trap or have fallen behind on cleanings, request a free quote from licensed providers in your area to get back on track quickly.

The Bottom Line

FOG compliance isn't just about avoiding fines — though those fines can be substantial. It's about running a responsible food service operation that protects your community's sewer infrastructure, the environment, and your own business.

The restaurants that stay out of trouble are the ones that treat grease trap maintenance as a routine operating expense — not an afterthought. Get on a cleaning schedule, keep thorough records, train your staff, and know your local regulations inside and out.

If you're unsure where to start, our state-by-state compliance guide can help you understand the requirements in your area. And when you're ready to find a reliable grease trap service provider, search our directory to find licensed companies near you.

Related articles:

• What Happens If You Don't Clean Your Grease Trap? (Fines, Closures & Worse)
• Grease Trap Cleaning Cost in 2026: What Restaurant Owners Should Actually Expect to Pay
• How Often Should You Clean Your Grease Trap? (State-by-State Guide)