Trade waste is generally considered to be the liquid waste discharged to a sewer from commercial and industrial processes. Domestic waste from activities like cooking dinner, having a shower or flushing the toilet isn't 'trade waste'.
The problem with trade waste is that it ends up in our sewerage system, which isn't designed for this discharge! GWMWater sewerage systems were designed many years ago to carry predominately domestic wastes, which are generally of a very predictable quality. Unless we closely monitor trade waste discharge, it can put increased stress on the sewerage system and has the potential to create serious problems for public health, the environment and treatment plants, as well as our staff and contractors.
Important - From 1 July 2021, you can't lawfully move reportable priority waste without being fully onboarded into the Environment Protection Authority's Waste Tracker. If you require assistance to complete your sign-up, please call EPA on 1300 372 842.
Trade Waste Agreements
Before discharging trade waste, all businesses using a commercial property for their commercial or industrial processes must enter into a Trade Waste Agreement with GWMWater.
What type of agreement you apply for and the rules you must comply with depend on the classification of your business. We classify businesses into five categories from Category 0 to Category 4, based on a number of factors, including:
- business location
- volume of discharge
- nature of business activity
- quality of waste
- compliance and performance history
- risk to health and safety, the sewerage system or environment.
Categories 1, 2, 3 and 4 need to complete an application to discharge trade waste in order to enter into a Trade Waste Agreement. Category 0 need not apply as they are automatically entered into a Trade Waste Agreement.
Apply to discharge trade waste
Trade waste categories
Non-major trade waste
These are generally business types in the table below:
Food preparation |
Petrol, Oil, Grease |
Photographic, X-Ray |
Other Process |
| Bakeries | Radiator repairs | Photo processing | Specialist doctor (plaster) |
| Boarding houses (B&B) | Auto wreckers | Dental | Hobby clubs/crafts |
| Butchers | Lawn mower repairs | X-Ray and radiation devices (including medical practices) | Laundromats/dry-cleaners |
| Cafeterias | Mechanical workshops | Photographic | Boilers |
| Canteens | Engine/gearbox reconditioning | Kennels | |
|
Clubs (with hot food preparation) |
Panel beating/spray painting | Building services (air conditioning) | |
| Coffee/sandwich shops | Vehicle washing | Food/chemical processing manufacturing | |
| Commercial kitchens | Service station | Fish- fresh (retail store) | |
| Community halls | Car detailing | Municipal pool | |
| Delicatessen | Morgue | ||
| Donuts (in stand alone shops, bakeries or bread shops) | Septic tank contractors/portable toilet wastes | ||
| Function centres | |||
| Garbage washes | |||
| Hot take-away foods | |||
| Hotels | |||
| Hot bread kitchens | |||
| Ice-cream parlours | |||
| Hospitals | |||
| Motels | |||
| Restaurants | |||
| Take-aways | |||
| Schools (home science rooms) |
Category 0
The lowest category of trade waste producers, this category is for businesses that:
- have trade waste similar of a similar quality to residential waste and;
- discharge only small amounts of trade waste.
If your business is in Category 0, you don't need to make an application to discharge trade waste. On your correspondence from us (such as a water bill) it will be made clear that you're in Category 0 and have entered a default Trade Waste Agreement.
Categories 1 & 2
Category 1 is for businesses discharging:
- mainly kitchen or laundry waste but also includes wash water from places like garages, workshops and school laboratories
- volumes that don't exceed 750 kilolitres per year.
Category 2 is for businesses discharging:
- mainly kitchen or laundry waste but also includes wash water from places like garages, workshops and school laboratories
- trade waste in volumes over 750 kilolitres a year
- trade waste with only low levels of contaminates.
Category 1 and 2 businesses need a 'Consent to Discharge' from us before discharging any trade waste into the sewerage system. A Consent to Discharge is a form of Trade Waste Agreement. To get a Consent to Discharge complete a 
Trade Waste Application form : Trade Waste Application form - Word Version
Businesses in these categories will also generally need a pre-treatment device or grease trap installed prior to a Consent to Discharge being issued. View our pre-treatment device and grease trap requirements.
Major trade waste
Major trade waste businesses are bound by the following criteria:
Parameter |
Concentration Threshold(< means less than) |
| Biological Oxygen Demand | < 600 mg/L |
| Suspended Solids | < 600 mg/L |
| Nitrogen | < 150 mg/L |
| Phosphorus | < 30 mg/L |
| Total Dissolved Solids | < 200 kg/day |
Category 3
We classify Category 3 businesses by their large discharges and the contamination of their waste. Both the volume and nature of their trade waste makes Category 3 establishments a greater risk to our sewer system and treatment processes then category 1 and 2 customers.
Category 3 businesses must complete an application to discharge trade waste and enter into a Trade Waste Agreement before discharging trade waste.
Category 4
Trade Waste from Category 4 business has characteristics that are outside the limits set the Customer Charter and the agreement. However, it's still capable of being treated by GWMWater’s wastewater treatment facility.
Category 4 businesses must complete an application to discharge trade waste and enter into a Trade Waste Agreement before discharging trade waste.
Trade Waste Customer Charter
Information about the trade waste services performed by GWMWater and the respective rights and responsibilities of GWMWater and its customers.
Trade Waste Customer Service Code
Apply to discharge trade waste
Categories 1, 2, 3 and 4 need to complete an application to discharge trade waste in order to enter into a Trade Waste Agreement. Category 0 need not apply as they are automatically entered into a Trade Waste Agreement.
Trade waste grease trap size requirements
Restaurant
Seating |
Discharge rate (litres discharged per day) |
Grease trap size required (litres) |
| 1 to 15 | 100 | 100 |
| 16 to 38 | 600 | 600 |
| 39 to 69 | 1100 | 1000 |
| 70 to 199 | 3200 | 1500 |
| 200 to 399 | 6400 | 2000 |
| 400 to 599 | 9600 | 3000 |
| 600 to 799 | 12800 | 4000 |
| 800 to 1000 | 16000 | 5000 |
Accommodation
Motel (number of rooms) |
Hospital/Nursing Home (number of beds) |
Discharge rate (litres discharged per day) |
Grease trap size required (litres) |
| Up to 50 | 1 to 69 | 1100 | 1000 |
| Up to 100 | 70 to 199 | 3200 | 1500 |
| Up to 200 | 200 to 399 | 6400 | 2000 |
| Up to 300 | 400 to 599 | 9600 | 3000 |
| Up to 500 | 600 to 799 | 12800 | 4000 |
| 800 to 1000 | 16000 | 5000 |