Restaurant Grease Trap Guide: Everything Melbourne Restaurateurs Need to Know

Why Every Melbourne Restaurant Needs a Grease Trap

Running a restaurant in Melbourne means navigating a complex web of regulations, and grease trap compliance is one of the most important—yet frequently misunderstood—requirements. Every restaurant that discharges trade waste into Melbourne’s sewer system must have a properly sized, regularly maintained grease trap. This is not optional: it is a legal requirement under your trade waste agreement with your water authority.

Failure to comply can result in fines, trade waste surcharges, and even the suspension of your trade waste permit—effectively shutting down your kitchen. This guide covers everything Melbourne restaurateurs need to know about grease trap selection, sizing, cleaning, and compliance.

For a broader overview of requirements across all food businesses, see our grease trap requirements by business type guide.

Grease Trap Sizing for Restaurants

Trap sizing is one of the first decisions you will face, and getting it right is critical. An undersized trap will fill too quickly, leading to overflows, blockages, and compliance failures. An oversized trap wastes money on installation and cleaning.

For most full-service restaurants in Melbourne, grease traps typically range from 1,000 to 2,000 litres. However, the exact size depends on several factors:

Number of meals served per day: A restaurant serving 200 covers will produce significantly more FOG than one serving 50.
Type of cooking: Deep frying, wok cooking, and chargrilling produce far more grease than steaming or baking.
Number of sinks and dishwashers: Each fixture connected to the trap adds to the flow rate calculation.
Kitchen size and layout: Larger kitchens with multiple prep stations require higher-capacity traps.

Sizing is calculated in accordance with AS 4674-2004, the Australian Standard for the construction and fit-out of food premises. Your plumber or grease trap installer should perform a detailed flow rate calculation before recommending a trap size.

Cleaning Frequency: How Often Should You Pump Out?

The cleaning frequency for your restaurant’s grease trap depends on your trade waste agreement and the volume of FOG your kitchen produces. As a general rule, Melbourne restaurants should expect the following schedules:

High-volume restaurants (200+ covers/day, heavy frying): Monthly pump-outs
Medium-volume restaurants (100–200 covers/day): Every 6–8 weeks
Lower-volume restaurants (under 100 covers/day): Quarterly pump-outs

Your water authority may specify a maximum cleaning interval in your trade waste agreement. Exceeding this interval—even if your trap appears to have capacity—is a compliance violation.

We offer flexible grease trap pump-out services tailored to your restaurant’s specific needs, from monthly scheduled visits to on-demand emergency call-outs.

Common Grease Trap Issues in Restaurants

Over years of servicing Melbourne restaurants, we have identified several recurring issues that cause compliance problems:

1. Trap Overflows Due to Delayed Cleaning

The most common issue is simply leaving cleaning too long. When a grease trap exceeds 75% capacity, FOG begins to bypass the trap and enter the sewer. This triggers trade waste violations and can cause blockages in downstream pipes.

2. Incorrect Plumbing Connections

Some restaurants have fixtures incorrectly connected—or not connected—to the grease trap. Every sink, dishwasher, and floor drain in the kitchen must route through the trap. Toilet and bathroom fixtures must not be connected to the grease trap.

3. Chemical Emulsifiers and Enzymes

Some restaurant operators use chemical degreasers or enzyme treatments in the belief that they dissolve grease and reduce the need for pump-outs. In reality, these products often emulsify grease temporarily, allowing it to pass through the trap and solidify further down the line. Most water authorities prohibit the use of these products.

4. Food Scraps Entering the Trap

Grease traps are designed to capture FOG, not solid food waste. When food scraps enter the trap—due to missing or damaged basket strainers—they accelerate sludge build-up and reduce the trap’s effective capacity. Always ensure strainers are in place and cleaned daily.

Compliance Requirements for Melbourne Restaurants

Staying compliant with Melbourne’s trade waste regulations involves maintaining several key elements:

Current trade waste agreement with your water authority (Yarra Valley Water, South East Water, or Greater Western Water)
Grease trap sized to AS 4674-2004 and approved by your water authority
Cleaning by an EPA-licensed transporter at the intervals specified in your agreement
Cleaning certificates and waste transport manifests kept on file for a minimum of three years
Accessible trap for inspection by water authority officers at any time

If your restaurant is located in a popular dining precinct like Fitzroy, Brunswick, or Richmond, you are likely to face more frequent inspections due to the high density of food businesses in these areas.

What Happens If You Do Not Comply?

Non-compliance with trade waste regulations carries real consequences for Melbourne restaurateurs:

Trade waste surcharges: Water authorities can impose additional charges for non-compliant discharge.
Infringement notices: Fines for breaching your trade waste agreement conditions.
Permit suspension: In serious or repeated cases, your trade waste permit can be suspended, meaning your kitchen cannot legally operate.
EPA prosecution: If grease reaches waterways, EPA Victoria can pursue prosecution under the Environment Protection Act 2017.

Choosing the Right Grease Trap Service

When selecting a grease trap cleaning provider for your restaurant, look for the following:

EPA-licensed waste transporter with current credentials
Experience servicing restaurants of similar size and cuisine type
Flexible scheduling that works around your kitchen’s operating hours
Complete documentation including cleaning certificates and waste manifests
Transparent pricing with no hidden surcharges

At Melbourne Grease Trap Cleaning, we specialise in servicing restaurants across every Melbourne suburb. We understand the pressures of running a kitchen and schedule our services to minimise disruption to your operations. Visit our restaurant services page to learn more about how we support Melbourne’s restaurant industry.