What are my legal obligations if I own a septic system?

Getting a system approved and installed is a one-off. The obligations that follow are continuing, they sit with the owner rather than the installer, and in Victoria they apply even to older systems that never needed a permit when they went in.1

The duties themselves

Victoria sets these out more explicitly than most states, and they are a reasonable guide to what is expected everywhere because the underlying concern is the same. Owners and occupiers have obligations under the Environment Protection Regulations 2021, and the local council enforces them.1

• Take all reasonable steps to make sure the system operates without posing a risk to human health or the environment.
• Make sure the system does not overflow.
• Notify the local council if the system poses a risk, or if there is a problem with it.
• Take reasonable steps to keep the system in good working order.
• Keep maintenance records, and provide them to the council when asked.1

Records are the part people forget. A service that happened but was never written down is hard to evidence afterwards, so keep the invoice and the technician's report with the property file rather than in an inbox.

If the property is rented

The duties split. The obligation to take reasonable steps to maintain the system does not apply to residential renters, and the owner must give written information about how to use the system to whoever is in management or control of it. Handing over the keys without handing over the instructions leaves a duty unmet.1

Where the waste goes is your problem too

Sewage pumped out of a septic tank is treated as priority waste, and all reasonable steps must be taken to ensure it goes to a place authorised to receive it. In practice that means using a contractor who can tell you where the load is going, rather than the cheapest truck available.1

Things that quietly breach the duty

• Driving or parking vehicles over any part of the system, including the land application area.
• Letting stormwater discharge into the system, or across the disposal or drain field.
• Covering the tank or the drain field, which also makes the access you are required to maintain impossible.1

After a fire or flood the advice is to have a licensed plumber or service technician assess the system rather than assume it survived, because a system that looks intact can have a compromised land application area.1