Installing a septic tank system
Septic tank systems, also known as on-site wastewater management systems, are installed to treat any on-site wastewater produced on your property.
These systems are only installed in areas where reticulated sewer is not available.
Properties in a sewer district must connect to the reticulated sewer system provided by your water authority. To check if your property is in a sewer district, contact either Western Water or Coliban Water.
All systems should be in compliance with AS1547 On-site domestic wastewater management.
Who can install a septic tank system?
A licensed plumber, registered with the Building and Plumbing Commission (BPC), must install the system in accordance with the Guideline for onsite wastewater management. These guidelines set out the roles and responsibilities of all parties, the requirements for designing and installing septic/on-site wastewater management systems, including the setback distances, and operating and maintaining your system.
If you are unsure if your plumber is registered, you can search the register.
What do I need to install a septic tank system?
You may need to have a Land Capability Assessment (LCA) of your property to decide the most suitable system to treat your wastewater. If this is required, a copy of this report will need to be included with your permit application.
You may also need a planning permit before starting any work. If a planning permit is needed, your application to install, replace or alter a septic system cannot be assessed until you have received your planning permit. Conditions on your planning permit may limit the choice, location and installation of your system.
If you require a planning permit, the following information should be considered when submitting your planning application.
When designing the septic system and effluent disposal area the following must be considered:
- Future use of the land
- The location must meet the minimum setback distances to boundaries, watercourses (including dams), other buildings, swimming pools, tennis courts and driveways. These distances can be found in the Guidelines for onsite wastewater management (4.5).
- Keeping of livestock (cannot be on effluent disposal area)
- Proximity of nearby trees and native vegetation.
Owners may need to include the following information with the planning application:
- Location of existing septic system (this is so Council can be satisfied that the system will not be disturbed or built on)
- Capacity (L) of existing septic tank and whether it is an all waste system (toilet waste and sullage) or a split system
- Length and location of existing absorption trenches or irrigation area
- Whether effluent is discharged offsite (into the storm water drain)
- Other relevant information such as the location of outbuildings, dams, creeks and fences
- Location of effluent envelop—an effluent envelope may be designated on the site as part of the planning permit or Section 173 agreement. All wastewater must be disposed of within this envelope unless consent has been given for disposal to occur in another location.
- Land Capability Assessment (LCA) if required.
How do I obtain final approval?
To obtain a permit to use a septic tank system you need to:
- Ensure a final inspection is conducted, once the septic system has been installed and before it has been completely backfilled, fees for additional inspections may be charged (Two days' notice is required for requesting an inspection)
- Provide a Certificate of Compliance ( Building and Plumbing Commission)
- Provide a commission report (if applicable)
- Provide an accurate, to scale, as-constructed site plan
- Provide a copy of the maintenance service agreement (if Aerated Wastewater Treatment System)