Managing your commercial wastewater in NSW

Cleanawater on 3 March 2020

NSW has strict guidelines for the management of commercial wastewater. These include limits for pollutants and pretreatment solutions. Every business must obtain permission from their Local Water Utility (LWU) or Council before discharging wastewater.

Cleanawater offers wastewater treatment solutions for commercial wastewater generators. To learn more about our range of solutions, get in touch with our expert team.

Wastewater regulatory framework

The Water Services Association of Australia drives the country's approach to commercial wastewater management. They issue national guidelines, which get applied at the state level. One of their key documents for wastewater management is the National Wastewater Source Management Guideline.

In NSW, the Department of Planning, industry and Environment has outlined a state level approach for wastewater management. The two documents published for NSW are:

The final step in forming regulations from the State-level guidelines happens in local water utilities (LWUs) or Councils. Every commercial wastewater generator must comply with the regulations set out by their LWU.

What are the requirements for commercial wastewater management in NSW?

commercial wastewater management requirements

An overview of trade wastewater definitions and requirements is available on the NSW Department website. It can be summarised as follows:

  1. Managing commercial wastewater discharges is important for protecting the environment, council worker safety, and protecting the sewerage infrastructure. Failure to control discharges leads to corrosion problems, odour complaints and worker injuries.
  2. Every business intending to discharge wastewater to the sewer system must first obtain approval from their local Council. Wastewater must be pretreated to meet the Council specifications before discharge.
  3. The Council is responsible for setting acceptance standards and adopting a risk-based approach to wastewater management. Their role is assessing applications for trade wastewater discharge and monitoring compliance.
  4. Businesses are charged on their wastewater volume and concentration of pollutants.
  5. Trade wastewater is categorised based on risk:

Category 1

No or minimum pretreatment and minimum impact on the sewerage system.

Category 2

Requires prescribed pretreatment.

Category 2S

Discharges of a septic tank or pan content waste.

Category 3

Large discharges (> 20 kL per day) and industrial wastewater.


Businesses are encouraged to pursue strategies for reducing and improving their wastewater discharges. Practical tips include using water sparingly and preventing pollutants from getting into the wastewater in the first place.

Using screens and basket arrestors as well as grease traps where appropriate can improve the quality of wastewater and lower the volume. Both these factors have the potential to lower the wastewater discharge cost to the business. They also lower the pressure on treatment plants and therefore contribute to protecting the environment.

What treatment solutions are there for commercial wastewater in NSW?

Cleanawater offers wastewater treatment solutions and expert advice. We help businesses obtain wastewater discharge permits as well as maintain their compliance.

Oil water separators

Various industries from workshops to manufacturing plants use oil water separators. They are designed to reduce oil and other hydrocarbons from water to as low as 5 ppm. This is achieved by slowing down the flow of water and giving time for oil droplets to join together and rise to the surface.

The process of separation is aided by coalescing plates or media. Oil can be skimmed from the surface and disposed of by a licensed waste contractor. Clean water is discharged from the bottom of the separator to the sewer.

Wash bays

commercial waste wash bays

Wash bays are designed for industries that clean vehicles and equipment. These could range from large construction machines to small tools in a workshop. Wash bays can be permanent structures or portable units that are moveable. The heart of the wastewater management from a wash bay is the sand filter, which catches solids.

Further downstream treatment may be necessary depending on the pollutants on the vehicles or equipment. Oil water separators are often required where vehicles or heavy machinery is involved.

Pump stations

Pump stations are usually installed where the fall of a site does not allow for a natural flow of water to the treatment solution or sewer. Using a tank and pump, they allow businesses to control the flow of wastewater to the right place so that the environment is not contaminated.

Chemical Dosing

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Chemical dosing systems are specialised solutions that deal with specific pollutants. They control pH or add disinfectants to a wastewater stream. Different dosing chemical options are available and you should always consult a wastewater specialist to determine the best solution for your needs.

Talk to Cleanawater for expert advice

Contact Cleanawater for commercial wastewater treatment solutions and advice in NSW. We have more than 20 years of experience working in the Australian regulatory framework. Our technical experts can help you understand your permit conditions and help you achieve compliance.

Contact Cleanawater to find out more about our wastewater treatment solutions.