Commercial trade wastewater

Why you need our approval

Discharging commercial trade wastewater into our systems is an operational, environmental and safety risk for us and the community. That's why you must have our approval to connect your business to our systems, and properly install and maintain appropriate treatment equipment. This helps us meet our commitment to Greater Sydney to protect the health of the community and the environment. This page covers commercial trade wastewater. Find out more about industrial trade wastewater.

Defining trade wastewater
Trade wastewater is wastewater produced at industrial or commercial premises. It can be wastewater transported by vehicle, and includes septic effluent. It also includes wastewater from ships and boats, and run-off from contaminated surface water and groundwater.

Why we regulate trade wastewater

Trade wastewater may include substances that could affect the environment or the health of the community. It may even affect our ability to serve the community by damaging our equipment. Our requirements and conditions for accepting trade wastewater help us to:

  • prevent blockages in the wastewater system that could cause waste to flow into the environment, into the community or even back into your premises
  • protect people working in and around the wastewater system 
  • protect rivers and oceans
  • protect the wastewater system and water resource recovery facilities from damage so we can continue to serve the community
  • process wastewater and produce recycled water and good quality biosolids
  • encourage sustainability through waste minimisation, cleaner production and water conservation.

Businesses that produce commercial trade wastewater

If your business is in the list below (which includes automotive, food and photographic industries), you're classified as a commercial customerFor a complete list of commercial trade wastewater processes that require a formal written permit, refer to our Commercial customers – trade wastewater fees and charges (330KB) fact sheet.

If you're not a commercial customer, you might be an industrial customer. Industrial customers need different treatment equipment and may need to take samples before discharging industrial trade wastewater into our system.

If your business process isn't listed below or on the fact sheet, email

Business group


Retail food

Restaurants, takeaway food outlets, function centres, hospital and nursing home kitchens, caterers, butchers, delicatessens and retail bakeries


Service stations, panel beaters and spray painters, car detailers, car wash – hand wash and pressure spray, car wash < 12 kL/day, mechanical workshops and auto recyclers 

Commercial laundries

Laundromats, commercial laundries < 2 ML/year, and hospital, nursing home and hotel laundries


Minilabs, medical facilities using X-rays, graphic arts and professional photographic laboratories

Shopping centres with centralised pre-treatment

Shopping centres with shared pre-treatment other than grease traps


Craft breweries, municipal swimming pools and aquatic centres, cooling towers and boiler blowdown

Approval to discharge commercial trade wastewater

Some businesses must seek formal approval to discharge commercial trade wastewater, while others are 'deemed' to have permission. However, all commercial businesses must meet certain requirements before we allow them to discharge into our systems.

Our Responsibilities of connected customers policy (358KB) covers your rights and obligations when you're connected to our systems. If you're not sure whether your business is commercial or industrial, don't worry. Follow the steps below and apply anyway. We'll contact you.

Before you apply

You must make sure that the property owner or the managing agent:

  • knows that you're applying for a trade waste agreement
  • knows the type of business you're running on the property.

How to apply

  1. Complete an application for connection to discharge trade wastewater at Sydney Water Tap in. Your application must be approved by either the property owner or the managing agent on the property owner's behalf.
  2. Answer any questions we have if we need to contact you about your application, collect additional information or arrange to meet you at your property.
  3. Wait while we assess your application and notify you of any requirements. This usually takes less than 21 days.

You mustn't apply on behalf of someone else without their permission. We send the written approval to the property owner. You must tell us if you change the business activities on your site.

How to cancel

It's easy to cancel an existing commercial trade wastewater approval. You must apply at least 28 days before you stop discharging trade wastewater. This enables us to stop the trade waste charges from the date you stop discharging trade wastewater from the property.

Complete your application to cancel an existing trade wastewater approval at Sydney Water Tap inYou mustn't apply on behalf of someone else without their permission.

If you discharge trade wastewater without our approval, we may disconnect the trade waste service. We may also disconnect or restrict your water service. 

Fees and charges

Most commercial customers have standard commercial processes. These attract management fees and waste quality charges that cover our additional costs in managing and treating your trade wastewater. We define standard commercial processes in our Commercial customers – trade wastewater fees and charges (330KB) fact sheet.

However, trade waste fees and charges don't apply to deemed processes.

Your commercial trade wastewater requirements

All commercial businesses need our permission to discharge trade wastewater. To gain our approval, you must meet the requirements explained in your trade wastewater permit. 

Some substances cannot be discharged at all, and some pre-treatment equipment must not be connected to our systems. For example, sink-to-sewer waste disposal units, in-sink food waste disposal units and garbage grinders on business premises. 

Most commercial trade wastewater customers need to install and maintain pre-treatment equipment. Your permit will explain any conditions and pre-treatment requirements. These may include installing and maintaining specific pre-treatment equipment for your business activities.

What is pre-treatment?

Pre-treatment is the term used to describe the process and equipment required to treat wastewater before it's discharged into the wastewater system (sewer).

  • Pre-treatment doesn't include the use of additives
    Adding solvents, enzymes, mutant or natural bacteria, odour control agents and pesticides to grease traps or pre-treatment systems is not permitted.
  • Choose the right pre-treatment for your business
    You must only use items listed for use within our area of operations. The best option is to discuss your pre-treatment requirements with us before you purchase any equipment. Take a look at our directories of listed pre-treatment suppliers and equipment.

Do you manufacture or supply pre-treatment equipment?
If you're a manufacturer or pre-treatment supplier and want to have an item listed for use within our area of operations, you must submit a Trade waste pre-treatment listing request (833KB).

What can and can't be discharged to our systems

There are some things we don't allow to be discharged into our systems. For example, we don't allow sink-to-sewer waste disposal units, in-sink food waste disposal units or garbage grinders on business premises. Certain industries, such as breweries and medical facilities, pose significant risks if waste isn't properly managed.


Craft breweries are an emerging industry. Their trade wastewater can cause odours and accelerated corrosion in our wastewater system (sewer). Find out more about our Trade waste requirements for craft breweries (164KB) discharging less than 12 kL/day. 

Discharge from these types of facilities
  • hospitals
  • clinics
  • offices or surgeries of a medical doctor
  • dentists
  • convalescent or nursing homes
  • medical or veterinary laboratories
  • health transport facilities
  • other medical facilities.

You can discharge liquid waste to our wastewater system, including faeces and body fluids.

You cannot discharge solid waste. Solid waste includes hypodermic needles, syringes, instruments, utensils, swabs, dressings, bandages, any disposable paper or plastic items, any portion of human or animal anatomy, or any items that have been macerated.

Discharge from nuclear medicine units

Hospitals or veterinary premises with nuclear medicine units must ensure wastewater is discharged to our wastewater system at a controlled rate that we determine. You may be required to:

  • to install delay holding tanks
  • to restrict days and time of discharge
  • to sample your trade wastewater.

We assess each application for approval to discharge. Your site-specific conditions will be outlined in your individual commercial permit.

Expect to be inspected

Our business customer representatives will inspect your site and pre-treatment, and may enter your site to ensure your activities are in line with your permit. They may:

  • collect samples of your trade wastewater at any time, on any day
  • install and use online monitoring.

No one on the premises is permitted to impede or delay our representatives unless it's to ensure relevant safety precautions are in place.

Retail food businesses

Trade wastewater from retail food businesses contains organic material that can cause odours and accelerate corrosion in our wastewater system. It also contains greasy waste, which can become solid and block our systems. Wastewater may overflow into the environment or even back into your premises.

You must follow the requirements of your approval to minimise the impacts of your retail trade wastewater. 

What retail food businesses need to know

Automotive businesses

Because trade wastewater from motor trades contains petroleum hydrocarbons, solids, metals and chlorinated solvents and phenols, we have a range of special requirements you must adhere to. 

You must have our approval to discharge waste into our system and follow the requirements in your agreement to minimise the impacts of substances in trade wastewater.

What automotive businesses need to know


Deemed processes

While some businesses must seek formal approval to discharge wastewater, others are deemed to have permission. We call these deemed processes. Trade waste fees and charges don't apply to deemed processes. Deemed processes are business processes:

  • that we assess as low risk
  • that discharge small volumes of trade wastewater to our wastewater system (sewer).

See grease traps and treatment equipment to find out if your business has approval to discharge trade wastewater as a deemed process. But don't forget: even if you have deemed processes, you must continue to meet our pre-treatment, backflow prevention and other requirements. Only use pre-treatment items that are approved for use within our area of operations. Check out our listed pre-treatment for other businesses

If you're uncertain whether your business processes are deemed processes, just follow the steps above to apply for approval to discharge at Sydney Water Tap in. We'll discuss whether you need a permit and any requirements.