Grease Management for Restaurants & Commercial Kitchens

If you run a restaurant, pub, café, or food manufacturing facility, you are dealing with high volumes of Fats, Oils, and Grease (commonly referred to as FOG). When warm FOG is washed down the sink, it eventually cools in the underground sewer system, solidifying into rock-hard masses known as fatbergs.

Fatbergs cause massive environmental damage, severe flooding, and foul odours. Because of this, UK water authorities strictly enforce grease management regulations. Here is what every commercial kitchen operator needs to know.

The Legal Requirements

Under the Water Industry Act 1991, it is a criminal offence to discharge any matter into public sewers that may interfere with the free flow of wastewater. Furthermore, the Building Regulations mandate that commercial hot food premises must be fitted with a grease separator (grease trap) or other effective means of grease removal.

If your business is found to be the source of a fatberg blocking a public sewer, water authorities (like Thames Water) can and will prosecute. You could face unlimited fines and be forced to pay the massive costs of clearing the public sewer.

How Grease Traps Work

A grease trap is a plumbing device designed to intercept most greases and solids before they enter the wastewater disposal system.

Wastewater from your sinks and dishwashers enters the trap. Because FOG is lighter than water, it floats to the top, while heavier food solids sink to the bottom. The relatively clear water in the middle is then allowed to flow out into the main sewer line.

Maintenance is Non-Negotiable

A grease trap is only effective if it is regularly maintained. If the trap becomes too full, the FOG will simply bypass it and flow directly into the drains.

• Regular Emptying: Depending on the size of the trap and the volume of food you produce, it must be emptied and professionally cleaned every 1 to 3 months.
• Biological Dosing: Many modern kitchens use automated dosing systems that inject grease-eating bacteria into the drains daily to break down residual FOG.
• High-Pressure Jetting: Even with a grease trap, some FOG will escape. You must schedule regular high-pressure water jetting for your main drainage lines to strip away any buildup before it causes a blockage.

Best Practices for Kitchen Staff

Technology alone isn't enough; your staff must be trained in proper grease management:

• Dry Wiping: Staff must thoroughly scrape and dry-wipe all pots, pans, and plates into the food waste bin before they go into the sink or dishwasher.
• Collect Waste Oil: Never pour fryer oil down the drain. It must be collected in designated containers and removed by a licensed waste carrier.
• Use Sink Strainers: Ensure fine mesh strainers are fitted to all sinks to catch food debris.

Protect Your Business with CleverWorks

At CleverWorks, we help commercial kitchens across London stay compliant and open for business. We offer comprehensive grease management solutions, including grease trap cleaning, biological dosing installation, and scheduled high-pressure drain jetting.

Don't risk a closure or a fine. Contact CleverWorks today to set up a commercial grease management contract, or call us on 01932 544 095.