Helpful information

To protect human health and the environment it is vital we treat domestic wastewater. Where there is no public sewage network, then wastewater is treated through an onsite wastewater treatment system.

An onsite wastewater treatment system is needed where any home or commercial building is not connected to a public sewage network. This system is used to treat and discharge the wastewater within the property boundary of a home.


There are lots of types of on-site wastewater treatment systems.

People tend to be most familiar with septic tanks, which are a primary treatment system. Increasingly, home owners are choosing, or may be required by their regional council, to use more advanced secondary or tertiary treatment systems. These break down the waste more effectively, so are better for the environment and human health plus help prevent the risk of odour.


Anyone living on a property where there is no public sewage network will need an on-site wastewater treatment system to deal with wastewater discharge from toilets, kitchen, laundry and bathroom. These include:

  • Rural residential subdivisions
  • Lifestyle blocks
  • Coastal or lakeside holiday homes/baches
  • High country cabins/huts


There are a number of scenarios when you might need a new onsite wastewater treatment system, such as:

  • Building a new house
  • Renovating an existing  house and are required to upgrade the existing system
  • If the local council requests an upgrade of the existing system already on the property

What next?

  • Are you building a new house? Contact your local council to discuss the consenting requirements, particularly if you are in a sensitive environmental location. Or talk to us about the different onsite wastewater treatment systems Eloy Water offer and how we can help you.
  • Renovating an existing property? Talk to us about the system you currently have and how Eloy Water can assist you to upgrade your existing onsite wastewater treatment system.