Any on-site effluent disposal systems must be decommissioned once a property is connected to the sewer.
Septic tanks must be decommissioned to prevent them from collapsing in the future to avoid causing damage or injury. Under law, decommission septic tanks if any of the following applies:
- If ownership of the property has changed. New property owners are responsible for ensuring that septic tanks are decommissioned. Having proof of the decommissioning is recommended. This process is often negotiated during property settlement.
- If the building foundations will be built closer than 1.2 metres from the septic tank, or if a building is to be constructed above it.
- Before any building works start.
- Within 60 days if there is a ‘material change of use’ of the property. For example, if a residence becomes a business, decommission the system no more than 60 days after the change of use has occurred.
Decommissioning means that:
- Septic tanks, leach drains, and soak wells must be completely emptied by a licensed liquid waste contractor.
- Empty septic tanks, leach drains, and soak wells should be completely removed from site if possible. If it is not possible, remove lids and break up the bottom of septic tanks.
- The excavations, septic tanks and leach drains or soak wells have clean fill such as yellow sand. They have then been thoroughly compacted.
- Only licensed and approved personnel can decommission septic tanks. Visit the Yellow Pages for a list of septic tank removal companies.
Those considering purchasing a property should determine if decommissioning has already occurred. This is important due to the costs associated with decommissioning.
The City requires a statutory declaration from development or subdivision applicants confirming all septic systems have been decommissioned. The statutory declaration must be provided before the City approves such applications.
If you are decommissioning a system, it is best to complete a statutory declaration when this occurs in case you need it for future applications.
Download an example statutory declaration form (PDF 100KB).