Trade waste for businesses connected to CWMS

Trade waste is wastewater generated by an operating business. Trade waste generally requires additional treatment that is business-specific.

Authorisation to discharge trade waste into the CWMS

It is illegal for a business to discharge trade waste into the CWMS network unless authorised to do so.

A business must have the appropriate trade waste authorisation before works are undertaken.

Authorisations are site specific, so businesses operating from multiple sites will need authorisation for each site.

The conditions of the trade waste authorisation will impact the type of pre-treatment and plumbing work required.

Trade waste authorisations cannot be transferred to another business, or to the new owner of a business.

Business entities must notify Council when there is a change in business operations, including a significant change to the quality and quantity of trade waste. Contact us online or phone 8397 7444.

Applying for authorisation

You may need to consult with a wastewater engineer before applying as some technical information is needed, including:

  • Proposed rate of wastewater discharge
  • Names of all chemicals - including up-to-date material safety data sheets
  • Drainage plans for wastewater and stormwater
  • Type, specification and size of all pre-treatment devices

Apply for trade waste authorisation via: CWMS application form

New trade waste system

If you are installing a new trade waste system you also need to apply for on-site wastewater works approval

Landowner and tenant or lessee relationship

The application for trade waste authorisation must be made by the business entity. The business is responsible for compliance with the conditions of the trade waste discharge authorisation.

If a business owner refuses to seek trade waste authorisation or refuses to comply with the conditions of the trade waste authorisation, Council may take action under the Water Industry Act to prevent further discharge of unauthorised wastewater.

Pre-treatment of trade waste

Trade waste is pre-treated using physical, chemical and biological methods to improve the quality of wastewater before it is discharged into Council’s CWMS network.

Most trade waste can be treated using the common pre-treatment devices shown below.

Pre-treatment device Description 
Grease arrestors Used to intercept grease and fat. Typically required when hot food is prepared on the premises. Often used by butchers/poultry processors, cafes, restaurants, canteens, food courts and bistros.
Dry basket arrestor with fixed screens Used to intercept food scraps and solid waste. Typically required when there is a risk of solids entering the CWMS. Often used by butchers/poultry processors, bakeries, cafes, restaurants, canteens, and hairdressers.
Sink screen or strainer Used to intercept food scraps and solid waste like hair. Often used by hairdressers.
Cooling pits Used to cool down hot liquids. Often used at laundromats.
Oil water separators Used to separate oil from water. Often used in the automotive industry.


The trade waste authorisation will have conditions relating to maintenance of the pre-treatment devices. These conditions are developed from the information provided in your application.

It is the responsibility of the business to ensure that all pre-treatment devices are regularly serviced and maintained in accordance with the conditions detailed in the trade waste authorisation.

For guidance on basic pre-treatment requirements, please refer to SA Water basic pre-treatment requirements.

Trade waste audits

Council undertakes random audits to monitor business compliance, which may include water quality sampling.

For examples of businesses that generate trade waste, refer to SA Water’s trade waste guidelines and fact sheets