Growing desperation by Domestic and Commercial owners of sewerage treatment plants is resulting in a rapid increase in enquiries about the ability to convert existing systems. IE – Econova, Ozzi Kleen or Biolytic’s etc. to Advanced Enviro-septic.

It is driven by 2 aspects.

  • The cost being quoted between $18,000 and $20,000 to replace a failing HSTP with a new HSTP
  • the owners past experience of the high ongoing operational cost and heart ache caused by continued failures and health risks..

Solutions put forward in the past have always included the decommissioning of the existing treatment system tank and the supply and installation of a new unit. In many cases this cost is simply beyond the homeowners financial capacity. If an affordable solution is not available then community health risks continue to escalate.

In the cases we have looked at, the tank of the existing system has been in good condition and in all cases they have been poly tanks. Biolytics used an Everhard tank in early models, Ozzie Kleen and Econova are also poly tanks and are all capable of being converted to septic tanks.

All HSTP units have a pump out chamber, which can be utilised to pump primary effluent to the AES land application area.

By using the existing tank and distribution infrastructure to the land application area you save up to $3,500. All the internal components are removed from the failed HSTP except the power supply and pump.

The AES may even be able to be installed in the existing land application area as a semi raised bed. On most occasions the clogging layer is around the dripper or the irrigation surface has been sealed by a clogging layer. Excavation of this shallow layer can provide a clean open absorption layer.


Above is a photo of the internal weir baffle created which is installed inside the pump well. (The wall of the well becomes the baffle.) The owner of this HSTP spent $8,500 in 2 years on repairs and Maintenance. ( Conversion cost to an AES was approx $6,500 in Dec 2012.)