Grease traps and treatment equipment

Equipment you need to treat trade wastewater

Trade wastewater contains solids, oil, grease and other substances. If you discharge it directly to the wastewater system (sewer), it can cause blockages and overflows, overload wastewater treatment plants, and pollute our rivers and beaches. That's why you must have our approval to discharge trade wastewater. You need to apply for approval before you install grease traps and other pre-treatment equipment. Choose the right equipment, by selecting only pre-treatment items we've listed and following our requirements. You must use a licensed plumber to install the equipment.


What do you need to do?

 

Commercial customers

If you discharge commercial trade wastewater you:

  • must have our approval to discharge trade wastewater. Find out more about commercial trade wastewater and how to apply
  • may be required to install standard items of pre-treatment. See our list of pre-specified, standard equipment for deemed processes under other businesses below
  • must select the appropriate pre-treatment technology. Retail food and motor trades have particular requirements, which are outlined below
  • must install only the pre-treatment items that we've listed
  • must maintain your equipment.

 

Industrial customers

If you discharge industrial trade wastewater, you:

  • must have our written approval to discharge trade wastewater. Find out more about industrial trade wastewater
  • must meet our acceptance standards for specific substances found in trade wastewater
  • must install pre-treatment designed and sized to meet site-specific requirements as set out in your agreement
  • must maintain your equipment and follow our requirements 
  • must collect and analyse samples of your trade wastewater as specified in your agreement 
  • may need to engage a wastewater treatment specialist.

Not sure if you're a commercial or industrial customer?
Don't worry. Call us on 13 20 92 weekdays during normal working hours or email businesscustomers@sydneywater.com.au.


Choosing the right equipment

If you're discharging commercial trade wastewater, you must install standard items of pre-treatment. The type of pre-treatment required will depend on your business activities and processes. Food and motor trades industries have particular requirements and equipment, but all businesses must meet our conditions to remain connected to the wastewater system.

 

Pre-treatment equipment for retail food businesses

Most retail food businesses only need to install:

  • in-sink and in-floor bucket traps
  • a correctly sized grease trap.

Some processes may need additional pre-treatment, such as upstream grease removal devices or under sink pump units.

Read on to learn about grease traps and other treatment equipment for retail food businesses and shopping centres.

 

Our requirements

To find out about pre-treatment requirements for food businesses, read Plumbing for retail food businesses (450KB).

See more information below about requirements for shopping centres.

Choose the right equipment

Only choose pre-treatment we've listed and size it to meet your maximum hourly flow rate now and into the future.

Select from our Listed pre-treatment for food businesses to find out if a product is listed for use within our area of operations and who supplies it. 

Install the equipment

You must have a licensed plumber install your grease trap according to the manufacturer's instructions and the Plumbing Code of Australia, 2012.

If you manage a shopping centre, you may need multiple grease traps. Read more below.

Maintain your equipment

You must have a Wastesafe contractor regularly empty and maintain your grease trap. Learn about Wastesafe and select your Wastesafe transporter to empty your grease trap, clean it and maintain it.

Manage your wastewater

Follow our housekeeping tips to introduce cleaner production methods to reduce the amount of wastewater you produce.

Pre-treatment equipment for motor trades businesses

Most motor trades businesses need to install:

  • in-sink and in-floor bucket traps
  • an oil water separation system with a collection pit and pump.

Only use pre-treatment we've listed and size it to meet your maximum hourly flow rate now and into the future.

Read on to learn about oil and water separators and treatment equipment for motor trades businesses.

 

Our requirements

Whether you're a mechanic, run a service station, panel beaters, car detailers or a car wash, you need to follow our requirements to remain connected to the wastewater system.

To find out about pre-treatment requirements for your motor trades business, see the table below.

Choose the right equipment

Only choose pre-treatment we've listed and size it to meet your maximum hourly flow rate now and into the future.

Read more about requirements for service stations, panel beaters and spray painters, car detailers, mechanics, auto-recyclers and car washes. 

Select from our Listed pre-treatment for automotive businesses to find out if a product is listed for use within our area of operations and who supplies it. 

Install the equipment

Most motor trades businesses require an oil/water separator. Read more about oil separators and how to install them below.

Maintain the equipment

You must properly maintain your equipment according to the manufacturer's instructions to ensure you continue to meet our requirements.

Manage your wastewater

Follow our housekeeping tips to introduce cleaner production methods to reduce the amount of wastewater you produce.

Pre-treatment equipment for other businesses

There are varied pre-treatment requirements for other businesses. All businesses must meet our requirements to be connected to the wastewater system. 

Only use pre-treatment we've listed and size it to meet your maximum hourly flow rate now and into the future.

Read on to learn about requirements for deemed customers and other businesses.

 

Our requirements

To find out about pre-treatment requirements for commercial businesses with deemed processes, see the table below.

If you're discharging industrial trade wastewater, you may need a specialist to help you design site-specific treatment to meet our acceptance standards before you select from our listed pre-treatment items.

To find out more about acceptance standards, read our Industrial customers – Acceptance standards and charging rates (644KB) fact sheet

Read more about industrial trade wastewater.

Choose the right equipment

Select from our Listed pre-treatment for other businesses to find out if a product is listed for use within our area of operations and who supplies it. 

Install and maintain the equipment

There are many different requirements depending on your business. Follow any installation and maintenance instructions from the manufacturer to ensure your equipment continues to meet our requirements.

Manage your wastewater

Follow our housekeeping tips to introduce cleaner production methods to reduce the amount of wastewater you produce.


Grease traps

Grease traps are the most common form of pre-treatment for retail food and some other businesses. You need to properly install and maintain your grease trap to continue to meet our requirements. If you reduce the amount of waste you're producing, your grease trap will work better. You must never pour waste oil directly into the sink or you'll quickly overload your grease trap.

 

 

What you need to do

Why you need to do it

Engage a licensed plumber. When the work is complete, ask your plumber for a certificate of compliance.

The grease trap must be installed according to the manufacturer's instructions, our requirements and the Plumbing Code of Australia 2012.

Size the grease trap to meet your maximum hourly flow now and into the future.

An undersized grease trap will not treat your trade wastewater. We may ask you to install additional pre-treatment.

Install the grease trap as close to the source (kitchen area) as possible.

If you use long pipe runs, they can become clogged with grease. This can cause overflows in your property.

Install the grease trap so it drains by gravity to the wastewater system (sewer).

Using pumps adds complexity and additional costs. If your pump fails, the grease trap will overflow within your property.

Ensure your grease trap is regularly cleaned.

Grease traps must be pumped out regularly. Your waste contractor will pump out the contents of the grease trap, clean the internal surfaces and scrape the inside of the grease trap. 

We'll specify how often your grease trap needs to be pumped out.

Ensure adequate space above the grease trap (at least equal to the depth of the grease trap).

This allows enough space to open the grease trap lid, maintain it and get it pumped out.

Allow for safe and unrestricted access to inspect and service (pump out) the grease trap.

Your waste contractor must park the waste tanker close to the grease trap. Our representatives need safe access to check the performance of the grease trap.

Consider the need for fixed pump out lines.

Some situations require you to install a fixed pump out line, e.g. multi-storey buildings.  

A fixed pump out line runs from outside a building to a point near the grease trap. This enables your waste contractor to connect a vacuum tanker to the fixed pump out line at street level and use a flexible hose (attached to the other end of the fixed pump out line) to empty the grease trap.

 

Learn more

For more information about grease traps, read:

 

Under-sink pump units

It's better for grease traps to drain by gravity to the sewer. This causes fewer operating problems, but sometimes it's not possible. If the sewer grade does not permit a gravity connection, the preferred design is to drain through the grease trap to a pump well and pump to the sewer. The least preferred design is to pump to the grease trap. To find out more, read our Grease traps – under sink pump units (276KB) fact sheet.


Pre-treatment requirements for shopping centres

If you manage a shopping complex or small shopping centre, you may need to install multiple grease traps.

Communal grease traps must have the capacity to process the combined greasy waste output of each retail food outlet. You may need to allow extra capacity to allow for future changes.

There are different requirements depending on the size of your grease trap and you may need to install additional treatment equipment.

 

Grease trap requirements for shopping centres depend on the size of the complex and how much greasy waste they produce.

Small complexes

For small complexes (that require less than 30,000-litre total grease trap capacity), you may use communal grease traps. The maximum capacity for a grease trap is 5,000 litres.

You need separate grease traps for grouped businesses to ensure you don't exceed the limit. You can also install centralised pre-treatment equipment, such as dissolved air flotation or equivalent.

Large complexes

For large complexes (those with over 30,000-litre total grease trap capacity), you must have centralised pre-treatment, such as dissolved air flotation or the equivalent. Where exceptional circumstances prevent you installing a centralised pre-treatment system, we'll work with you and may approve alternative pre-treatment.


Pre-treatment requirements for motor trades

Activities

Minimum pre-treatment requirements

Service station with under canopy forecourt

Collection well with a sloped bottom and minimum working volume of 750 litres

  • Inspection opening on grill cover
  • Level indicator in collection well
  • High level in collection well triggers flashing light
  • Manual check of collection well before using keyed manual start switch
  • Keyed manual start switch located close to pit and pump

Oil water separator system

Bunded area around oil water separator

Wastewater discharge point located outside the bunded area 

Installation set up with hydrocyclone

Installation set up with coalescing plate separator

Panel beating and spray painting
Car detailer
Mechanical workshop
Auto recycler

Collection pit with an operating capacity of at least 500 litres

Oil water separator system sized according to influent flow rate (minimum size 1 kL/hr)

Installation set up with coalescing plate separator

Car wash – hand wash and pressure spray
Car wash – mechanical <12kL/day

Roof and bund wash area to exclude rainwater and install in-floor bucket traps

Collection pit with an operating capacity of at least 500 litres

Oil water separator system sized according to influent flow rate (minimum size 1 kL/hr)

No discharge of solvents to sewer

or

Bund wash area to exclude run-off from other areas and install an approved diversion system* 

Collection pit with an operating capacity of at least 500 litres

Oil water separator system sized according to influent flow rate (minimum size 1 kL/hr)

No discharge of solvents to sewer

* Fox Environmental Systems DD600 System

Installation set up with coalescing plate separator

 


 

Pre-treatment requirements for service stations 

We have specific installation requirements for service stations with under canopy forecourts. 

See our schematic diagrams for:

We have special requirements for service stations with under canopy forecourts.


Oil water separators

Oil water separators remove free oil from wastewater. Read more about the different types of oil water separator technologies below.

Before choosing your oil water separator system, read about listed pre-treatment for the auto industry

Installation

Before installing your oil water separator:

It must be installed according to:

  • the manufacturer's instructions
  • our requirements
  • the Plumbing Code of Australia 2012. 

Types of oil water separator technologies

Type of technology

How it works

Coalescing plate separator

This is a gravity separator with a plate pack fitted to remove oils and solids. It uses the difference in specific gravity (settling speed) between unmixable components of a liquid waste stream, such as engine oil and washwater.

The plates improve the gravity separation process by reducing the settling or rise distance. Wastewater is collected and pumped to the coalescing plate separator.

Vertical gravity separator

This oil water separator uses a vertical cylinder design containing a continuous truncated conical spiral pack to separate non-emulsified oils and sludges from wastewater. 

Wastewater is collected in a pit and pumped to the vertical gravity separator. 

Hydrocyclone separator system

This uses centrifugal force to separate oils from water.


Requirements for deemed processes 

Some businesses are deemed to have permission to discharge trade wastewater to our wastewater systems. We call these 'deemed processes'. You must still meet the requirements listed below or you could be disconnected. Deemed processes do not attract trade waste fees and charges.

If you're not certain whether your business has 'deemed processes', apply for approval to discharge and we'll advise you.

 

Deemed processes and their pre-treatment requirements

Deemed process

Pre-treatment requirements

Beautician, doctor's surgery, funeral parlour, school (ceramic and pottery room), venetian blind cleaning  

No pre-treatment required

Aquariums

Must meet Australian quarantine requirements

Building construction – slab formation

No discharge to our wastewater system (sewer)

Pipework with open connectors to be capped at all times or have an internal device fitted

Mobile carpet cleaners

20 micron filter unit

Cooling towers

Discharge not to exceed 500 litres/day 

Dental surgery

Amalgam trap and segregation of waste amalgam

Dental technician

Plaster trap

Dog groomer, pet shop (retail)

In-floor bucket trap, no organophosphates pesticides to our wastewater system (sewer)

Dry cleaners

Solvent recovery unit

Florist

No herbicide to our wastewater system (sewer)

Hairdresser

In-floor bucket trap and in-sink bucket trap

Optical lens grinding

Solids settlement pit

Residential garbage bin-wash area

Roof and bund bin-wash area to exclude rainwater and install an approved in-floor bucket trap

Discharge directly to the wastewater system (sewer) via floor waste

Use only soap-based products to clean garbage bins

or

Bund bin-wash area to exclude run-off from other areas and install approved diversion system*

Use only soap based products to clean garbage bins

*Fox Environmental Systems DD600S

Residential vehicle wash bay

Minimum 1,000 litres/hour oil water separator system or 1,000 litre general purpose pit

Display a sign stating 'No degreasing or mechanical work in the wash bay'

Locate vehicle wash bay on a roofed and bunded hard surface and install an approved in-floor bucket trap

Direct all washwater to the oil water separator or general purpose pit via floor waste

or

Minimum 1,000 L/hour oil water separator system or 1,000 L general purpose pit

Display a sign stating 'No degreasing or mechanical work in the wash bay'

Bund unroofed bin-wash area to exclude run-off from other areas and install approved diversion system*

*Fox Environmental Systems DD600

Sanitary bin washing

Screening and temperature control (less than 38° C)

Swimming pool (residential, hotel, hospital, club)

No open areas discharging rainwater to our wastewater system (sewer)

Train platform and internal carriage cleaning

In-floor bucket trap and in-sink bucket trap

No open areas draining to the wastewater system (sewer)

Wash water generated by the washing of painting and plastering equipment such as brushes, trays and spatulas (construction site only – medium to high-density developments, mixed developments, commercial and industrial developments)

Minimum 1,000 litre general-purpose pit or solid settlement pit

Note: We must authorise all pre-treatment apparatus

 

Not sure whether your business processes are deemed processes?

If you're discharging trade wastewater and you're not listed as a deemed process, you must have our written approval. If you can't find it or you're not sure if you have our written approval, email businesscustomers@sydneywater.com.au.

If you don't have written approval and you're discharging trade waste, you must apply at Sydney Water Tap in.


Listed pre-treatment equipment and suppliers

How to have your pre-treatment equipment listed

If you manufacture or supply pre-treatment equipment and you want to have an item listed for use within our area of operations, please email us at TWProductApprovals@sydneywater.com.au.