In non-sewered areas, septic tanks systems were once the norm. As more Councils require stringent effluent discharge quality, the installation of secondary treatment system (STS), formerly called an aerobic treatment unit (ATU) in WA, is steadily increasing. These whole-house systems treat all wastes to a secondary standard and the discharge water can then be used to irrigate gardens.
STS are biological units and they require servicing and maintenance by experienced, registered service technicians. The monitoring of this service work is the responsibility of local Council. Unfortunately some Councils do not have the staff to keep tabs of this and systems are not being monitored and looked after properly, and some systems are under-performing.
This problem is being addressed by the state Department of Health which wants all STS units installed in WA to meet the updated Australian Standard AS1546:3:2017, which sets out the performance requirements of STS units. These conditions are stringent, but will ensure that all STS units are designed and operate to meet good effluent discharge so that there is minimal discharge of nutrients and disease organisms to the environment.
All STS units have to be tested to this new standard by the end of 2020, or they will not be permitted to be installed in Australia. Several systems have undergone testing and we know that the Kingspan BioFicient STSunit has passed.
We suspect that some manufacturers will not undertake testing as the cost is over $100,000 and there is the fear that the system may not pass. This will potentially reduce the number of systems that can be installed, but will ensure that what is installed will perform as expected.
WA's first secondary treatment system (STS), formerly called an aerobic treatment unit (ATU) in WA, to be passed to the new Wastewater Standards
Find out more about the newest STS unit approved to the new WA wastewater standards in the domestic marketplace, the Kingspan BioFicient STS.
Has Local Council Requested a Nutrient Reduction ATU system?
The Aquarius STS system with nutrient reduction (NR) is a requirement for some councils.
Water Installations can supply, install and service these systems as we are authorised Aquarius agents.
The Aquarius O-2 NR and O-3 systems treat the water to reduce phosphorous and nitrogen, which is essential if the discharge effluent is being recycled in water catchment areas or sensitive environmental areas.