OWMS have the potential for major environmental and human health risks. Poorly installed or maintained systems, particularly old legacy systems, can create serious hazards. These might include polluted drinking water, contaminated land and water bodies, and offensive odours.
Owners and occupiers have a responsibility to minimise these risks, so far as reasonably practicable.
Read more about OWMS and wastewater on the EPA website .
To keep the system working well
✔ use biodegradable soaps and low-phosphorus, low sodium detergents
✔ arrange for regular servicing of treatment plants
✔ keep livestock and vehicles off the system
✔ Divert stormwater runoff away from trenches or irrigation areas
x don’t use powerful bleaches, whiteners, nappy soakers, spot removers and disinfectants
x don’t put chemicals or paint down the drain
x don’t put pads, tampons or nappies into the system
x don’t build over the system (driveways, sheds, units etc.)
To reduce sludge building up in the tank
✔ scrape all dishes to remove fats, grease and food scraps before washing
✔ keep food waste out of the system
✔ Pump out the tank at least once every 3 years
Avoid overloading the system
✔ space out water use as evenly as possible
✔ wash clothes only when there is a full load
✔ install water conservation fittings
✔ take showers instead of baths
x avoid doing all the washing on one day
x avoid using the washing machine and dishwasher at the same time
Servicing of Aerated Wastewater Treatment Systems (AWTS)
An AWTS is a purpose-built mechanical treatment system used to treat wastewater to a secondary quality. Wastewater flows through a series of treatment and disinfectant processes where it is usually dispersed via sub-surface irrigation. Compared to a standard septic tank, an AWTS requires quarterly servicing by a suitably qualified technician.
As an owner of an AWTS you should:
✔ Have it serviced every 3 months or as required by EPA certificate of approval to maximise the performance of your system. This service needs to be undertaken by a competently trained person or company and they should be contracted to undertake the task. A copy of the maintenance report is to be submitted to the Council after each service.
✔ Have it de-sludged once every 3-5 years.
✔ Ensure it is accessible for servicing and other works. The system should be free of overgrown vegetation, rubbish and any other obstructions.
✔ Have it repaired quickly if the alarm goes off. The alarm indicates that one of the mechanical devices that operate within the system has failed or malfunctioned.
✔ Routinely check the irrigation filter (between the irrigation field and the AWTS) and clean it if needed. Please be careful when cleaning the filter because you will be dealing with effluent that could contain pathogens that can affect your health.
✔ Routinely check that the irrigation system is working adequately. Some common signs that the irrigation field is struggling or failing include water ponding, the ground being heavily saturated, or significant vegetation die off.
There are several service agents that operate within or regularly visit the southwest region to service ATWS. If unsure, please contact the company or plumber that provided or installed your system.