Every commercial kitchen in the Port Macquarie-Hastings region that discharges to the sewer system, or to an on-site system, is required to install and maintain a grease trap. Failure to do so, or failure to maintain it properly, is a breach of PMHC trade waste requirements, NSW EPA licensing conditions, and the NSW Protection of the Environment Operations Act 1997. The consequences range from Council notices and fines to prosecution and business closure.
Quick answer (BLUF)
Grease traps are mandatory for commercial food businesses (restaurants, cafes, bakeries, takeaways, clubs, aged care kitchens, and others) in Port Macquarie-Hastings. PMHC requires a trade waste agreement for sewer-connected businesses; businesses on on-site systems need an OSSM approval incorporating grease trap requirements. Cleaning frequency is set by the agreement, typically every 1-4 months depending on business size and oil loading. Annual contracts are the most cost-effective approach.
What is a grease trap and why is it required?
A grease trap (also called a grease interceptor or GI) is a plumbing device that intercepts fats, oils, and grease (FOG) from kitchen wastewater before it enters the sewer or on-site system. FOG is a persistent problem in wastewater infrastructure because:
- It solidifies as it cools in pipes, causing blockages
- In sewer systems, FOG combines with other materials to form “fatbergs” that block collector mains
- In on-site septic systems, FOG from kitchens accelerates biomat formation in absorption trenches, drastically shortening their life
- FOG discharged to waterways is an environmental offence under NSW EPA legislation
For food businesses discharging to PMHC’s reticulated sewer, a Trade Waste Agreement with the water utility mandates grease trap installation and sets out maintenance requirements. Non-compliance with the trade waste agreement is an offence.
For food businesses on on-site sewage management systems (rural properties, catering facilities, agricultural tourism venues), the grease trap is a component of the OSSM system and must be included in the PMHC approval.
Types of grease traps used in Port Macquarie
Passive (gravity) grease traps: Small under-sink units or outdoor underground vaults. FOG separates from wastewater by gravity, the grease floats and is retained; the clarified water passes through. Common in small cafes and takeaways. Outdoor passive traps are typically 1,000-4,000 litre underground concrete or poly tanks.
Automatic grease removal devices (AGRD): Mechanical systems that skim FOG automatically from the trap surface at regular intervals. More expensive but require less frequent pump-outs. Suited to high-volume operations.
Hydromechanical grease interceptors: Compact, high-flow units with internal baffles and flow control. Used where space is limited and rapid flow-rate management is needed.
Regulatory requirements: who issues what
PMHC sewer-connected businesses: PMHC’s trade waste management program issues Trade Waste Agreements that specify grease trap size, type, location, and maintenance requirements. The agreement must be in place before the business opens.
On-site systems (OSSM): Food businesses not connected to sewer need a grease trap as part of their PMHC OSSM approval. The grease trap must be appropriately sized for the commercial kitchen output and must be maintained under the approval conditions.
Sizing a grease trap for your business
Grease trap sizing is determined by the kitchen’s peak hydraulic flow rate. Key factors:
- Number and type of sinks (pot wash, prep, dishwasher pre-rinse)
- Commercial dishwasher capacity and usage frequency
- Deep fryer volume and frequency of oil disposal
- Overall covers and service sessions per week
A licensed trade waste contractor or plumber can calculate the required trap size and select an appropriate unit. Undersized traps fill quickly and overflow, a common compliance failure in rapidly growing businesses. If you’re mid fit-out rather than already operating, our guide to grease trap sizing and council signoff for a commercial kitchen fit-out covers the sizing decisions and approval timeline in more depth, including the common mistakes that delay an opening date.
Cleaning frequency and compliance
Trade waste agreements specify minimum cleaning intervals based on the business’s assessed oil loading. Common intervals:
| Business type | Typical cleaning frequency |
|---|---|
| Small cafe, bakery (under 50 seats) | Every 3-4 months |
| Medium restaurant (50-100 seats) | Every 4-8 weeks |
| Large restaurant, club kitchen | Every 2-4 weeks |
| High-volume takeaway or food court | Weekly to fortnightly |
| Rural OSSM food business | Monthly to quarterly |
The trade waste agreement sets a maximum interval, you can clean more frequently, but not less.
Record-keeping obligations
Businesses must maintain a service record for their grease trap. This typically includes:
- Date and time of each service
- Volume removed (waste manifest)
- Contractor details (licensed liquid waste contractor)
- Waste disposal destination (licensed waste facility)
Grease trap waste is classified liquid waste under NSW EPA regulations. It must be transported and disposed of by a licensed liquid waste contractor.
Keep service records for at least 3 years and have them available for inspection by PMHC’s environmental health officers.
FAQs
Do I need a grease trap if I only serve cold food (sandwiches, salads)?
Potentially yes, depending on your waste stream. PMHC’s trade waste requirements depend on the type of food prepared and the wastewater generated, not just whether food is hot or cold. Businesses that use a commercial dishwasher, a food prep sink, or any oil-containing food products typically need a grease trap. Check with PMHC’s trade waste team for a determination based on your specific menu and kitchen setup.
What about a community hall or sporting club canteen that only trades on event days?
The same grease trap requirements apply, but sizing needs to reflect the concentrated food service volume of a carnival day or grand final rather than the venue’s quiet weeks between events, and any grease trap installed years ago for a smaller canteen menu can be well undersized once catering ramps up for bigger events. See our guide to event-load septic planning for sporting clubs and community halls for how to plan grease trap and septic servicing around a big events calendar.
What happens if my grease trap overflows?
An overflow that reaches the sewer, stormwater system, or any waterway is an environmental offence under the POEO Act. You are required to notify PMHC and the EPA immediately. Beyond the legal obligations, an overflow is typically the result of inadequate cleaning frequency or a system that is undersized for the business’s actual output.
Can I clean my grease trap myself?
The pump-out and waste disposal component must be done by a licensed liquid waste contractor, this is an EPA licensing requirement. You can do supplementary maintenance between professional services, but the regulated service that generates the waste manifest must be performed by a licensed operator.
How much does commercial grease trap servicing cost in the Hastings region?
A standard small-business (1,000-2,000 L) grease trap pump-out and service typically costs $200 to $400 per service. Annual contract pricing for regular services is usually more cost-effective. Hastings Septic Co offers commercial grease trap contracts covering Port Macquarie, Wauchope, Laurieton and surrounding areas.
What about a rural cellar door, brewery or distillery that isn’t a standard commercial kitchen?
The grease trap requirements for any food-service kitchen at a cellar door, brewery or distillery are the same as for any commercial kitchen, but these venues often also generate high-strength production wastewater (fermentation waste, wash-down water) that needs to be managed separately from both the grease trap and any domestic system on the property. See our guide to winery, brewery and distillery wastewater on septic for how the two wastewater streams are typically handled.
Does a childcare centre that prepares meals onsite need a grease trap too?
Yes, on the same basis as any other commercial kitchen. A childcare centre also carries a higher hydraulic and solids load overall than a house of similar size, given the number of children and staff passing through daily. See our guide to childcare centres on septic: compliance and load for what that means for approvals and servicing.
What about a farm stay or glamping site with a shared camp kitchen or breakfast service for guests?
The same grease trap requirements apply if food is prepared on-site for guests, whether that’s a full camp kitchen or a simpler breakfast preparation area, on top of a wastewater system sized for the accommodation’s total peak guest capacity. See our guide to farm stay and glamping wastewater systems in NSW for how the two obligations fit together on a rural tourism site.
We run a shared kitchen across several letting cabins or units on one property. Does the wastewater side need special attention too?
Yes. Where a shared guest kitchen sits alongside a septic or onsite system serving multiple dwellings or cabins on one title, the grease trap and the household wastewater system are two separate compliance requirements, and the septic side needs to be sized and approved for the combined occupancy of every dwelling connected to it, not assessed as a single household. See our guide to shared septic systems for multiple dwellings in NSW for what changes when more than one dwelling relies on the same system.