The Environment Protection Act details the permit process that applies in Victoria for the installation/alteration and use of domestic and some commercial wastewater managament systems.
The Act uses the term 'septic tank system' for a range of system types which treat wastewater with a volume of less than 5000 litres flow per day and where a connection does not exist to a township reticulated sewerage system.
A two tier approvals process applies which provides for:
- The Environment Protection Authority to approve system types for use in Victoria; and
- The local municipal Council to approve individual installations.
The installation must be a type of system covered by an EPA Certificate of Approval, compliant with conditions of the approval and be appropriate for the style of development and the intended site.
Full details of approval systems for use in Victoria together with conditions and limitations can be found on the EPA website: www.epa.vic.gov.au
Council also provides detailed guidance for the public which is based on the EPA Code of Practice for Septic Tanks and the most relevant certificates of approval. Significantly more detail including the role of the EPA, Council, Land Capability Assessors, Plumbers and Drainers, and the role of landowners and occupiers is contained within the EPA Code of Practice Publication no 891 dated March 2003. System Design
In summary, the design and selection of an appropriate system needs to consider:
- Wastewater volumes involved
- Site constraints such as setbacks to waterways
- Land space availability and suitability
- Owner preference and cost
A formal Land Capability Assessment (LCA) needs to be undertaken by an appropriately qualified person or business who can assess the above matters. The EPA have published a document (No 746.1) titled "Land Capability Assessment for Onsite Domestic Wastewater Management" which includes a summary example of the details of such an assessment including the parameters that should be considered and whether the results are rated as 'very good' through to 'very bad' in respect to capability. As the site's capability decreases, a higher standard of treatment, increased setback distances and/or a greater level of owner involvement may be necessary. Potentially some allotments will be assessed as not suitable for development or only suitable for a small scale of development that produces less wastewater.
Once the Land Capability Assessment report has been obtained a system design and plan should be developed which details the proposal. The Council guide should be reviewed to ensure the design details and plan will be complete and consistent with EPA standards. System Application
The last page of Council's Guideline includes a standardised application form for completion and lodgement together with:
- copy of the LCA
- plan of proposal
- prescribed fee ($450 for installation, $380 for significant alterations, $230 for minor alterations)
Please note that a Building Permit relating to a new development to be serviced by a septic system or a redevelopment such as an additional bedroom or ensuite proposal which increases the potential wastewater generated cannot be processed until the septic system has been assessed and consented to.
Care should also be exercised to ensure any site redevelopment is not going to adversely affect a system's performance. Operation and Maintenance
All septic systems require some maintenance to ensure their ongoing proper performance. Some systems such as sewerage treatment plants require 3 monthly servicing, the traditional septic tank generally needs desludging at 3 yearly intervals.
Further details regarding this matter are contained within the system specific Certificate of Approval.
Systems installed in recent times are required to be assessed every 3 years to confirm their continuing suitability for use, with a copy of a report by an appropriately skilled person or service company provided to Council. Any deficiencies need to be addressed and in some cases this will require a permit to be issued by Council before the works are undertaken. Wastewater Management Plans
In accordance with the direction of the EPA Code of Practice, Council is developing a Domestic Wastewater Management Plan. This plan will identify priority areas for Council to reassess system performances particularly in relation to very old systems where anecdotal evidence suggests system failures exist or where a system failure is likely to lead to a public health concern.
The Wastewater Management Plans will also detail Council's current practices and procedures in regard to septic system assessment before, during and after installation and will include the further development of a compliance programme to ensure permit conditions are met.