Get to Know Your Effluent System

If your home is not connected to Council’s reticulated town sewerage system, then you are likely to dispose of your wastewater via an on-site sewage management system. This page will help you find out what kind of system is installed at your place. 


Septic Tank

What Kind of System do I Have?

Although there are many variations of on-site effluent systems, there are 3 main types in use in the Shoalhaven and they are:

  • Septic systems
  • Pump-out systems, and
  • Aerated Wastewater Treatment Systems (AWTS) 

Septic Systems

Septic tanks and trench style absorption field systems are the most common type of septic system. Septic tanks treat both greywater (from shower, sinks and washing machines) and blackwater (toilet and kitchen water). They provide only limited treatment through the settling of solids and the flotation of fats and grease. Bacteria in the tank break down the solids over a period of time. Wastewater that has been treated in a septic tank can only be applied to the land through a covered soil absorption system.

A standard septic tank may look something like this:

Standard Septic Tank

Pump-Out Systems

This is the kind of system you will have if you are on a regular pump-out schedule. Pump-out systems involve the preliminary on-site treatment of wastewater in a septic tank, followed by collection and transportation of the treated wastewater to a Wastewater Treatment Plant. Pump-out systems use road tankers to transport the effluent. A household septic tank on pump-out usually consists of two round concrete tanks with lids placed close to each other and they are connected by a pipe. To allow the road tanker to pump out the system, a standpipe is located at the boundary of the property; this is where the tanker connects to your system.

A pump-out system standpipe may look like this:

Pumpout Standpipe

Aerated Waste Treatment Systems (AWTS)

The AWTS system consists of two tanks (sometimes within a single larger tank). The first is a basic septic tank where solids settle, and anaerobic digestion occurs. In the second, oxygen is bubbled through the effluent to encourage aerobic bacteria to digest the waste. Finally, the effluent is disinfected using chlorine or ultra-violet light before being pumped to an irrigation area. The effluent from an aerated septic tank is usually treated and disinfected to a standard suitable for irrigated onto land. An AWTS is most often a concrete tank installed underground so you only see the lid and electrical control box.

An AWTS system may look something like this:

AWTS System

Brands of AWTS include: 

  • Biocycle
  • Bioseptic 
  • Econocycle
  • Envirocycle 
  • FujiClean 
  • Garden Master 
  • Taylex 
  • Supertreat 
  • Ultraclear

Care and Maintenance

Regular care and maintenance of your system is important. If you’re experiencing warning symptoms, there are several products on the market that can help maintain a healthy system. Most are enzyme activated products that digest fats, grease and other wastes that can clog the system and cause odours. Usually dosed through the toilet and then flushed, it will significantly increase the time between cleanouts.

Tried these steps and still have a problem? It’s probably a good idea to request a clean-out of your system.