Septic Tanks

As a property owner, it is your responsibility to know whether your property is connected to the sewer, or if it relies on an Onsite Wastewater Management System (Septic Tank).

Victorian Government legislation requires all onsite wastewater systems to be registered with Local Council and for councils to regulate and oversee their use.  This helps to ensure that the risks to public health and the environment posed by these systems are minimised.  

If you already own or live on a property that is not connected to the sewer system, and you are unsure if your property has a septic system /  on-site wastewater management  ystem, you can contact Council Environmental Health Team by email eho@sthgrampians.vic.gov.au  or call us on 03 5573 0444

We can do a property search and, depending on the age of the system, we may be able to tell you where your system is located, where your treatment tank and effluent area should be.

Onsite Wastewater Management Systems are a necessary part of life in rural towns and in the country that are not connected to a reticulated  sewerage system. 

As a property owner or occupier, you have a responsibility to maintain your system and to ensure that it does not pose a risk to you, your family, and the wider community. 

All Onsite Wastewater management systems contain bacteria, but they can also contain other pathogens that can cause disease – either by direct contact, or through exposure to contaminated surfaces, water, and vegetation.  These systems can also contain toxic or flammable gases.

To minimise the risks:

• Always keep your system maintained, and ensure that you regularly check the areas around your tank and the absorption field where waste is discharged
  
  
• Regularly inspect lids and covers to ensure that they are fitted correctly, and that children cannot open them.
  
  
• Don’t attempt to repair a system yourself – use an experienced and knowledgeable contractor
  
  
• Never enter a septic tank, and avoid breathing the fumes that may be present when you open the cover
  
  
• Never smoke or use naked flames near an open tank
  
  
• If you have a powered system, the power should remain on at all times so that the unit can operate properly - even if the house is temporarily unoccupied.  If you are checking the unit, make sure the power is switched off before opening the lid.
  
  
• Don’t let children play near the system or the evaporation lines.
  
  
• Don’t build, concrete, or pave over, over the system or the absorption field, you need to be able to access the system at all times.
  
  
• Don’t drive vehicles over your system of the absorption field, you want to avoid damaging or compacting any part of it.
  
  
• Always wear gloves when checking your system, and thoroughly wash your hands afterwards. 

It is important that you know where your on-site wastewater management system (septic) is located, including the tank, effluent drains, inspection and access openings to make sure your system is working properly at all times.

For the correct operating and maintenance of your system you need to refer to your system’s manufacturer recommendations and also the conditions on your onsite wastewater management system (septic) Permit.

If your system is not operating properly:

• Polluted water from your septic system carrying bacteria and viruses could make people unwell.
• The polluted water can have a damaging effect on the environment.
• You may be up for expensive repairs and or replacement costs.

Signs of a failing system

• Rotten smells
• Sewage smells
• Alarm system on your system regularly sounding
• Blockages
• Water backing up in the sink, shower or washing machine
•  Toilets, showers and sinks taking longer than normal to drain.
• Pipes making noises or gurgling when draining
• High sludge levels in the treatment tank
• A lush green growth down slope of the effluent drains.
• Soil effluent (absorption) trench lines that become waterlogged following storms
• Effluent visible or pooling in areas around your system.
• Ground soggy and damp where the system effluent trenches or irrigation are
• Presence of dead and dying vegetation around, particularly down slope of the land disposal area.

Recognising the signs that your system may not be functioning properly means you can quickly act to fix the problem before things get worse, or the system fails. You also have a legal responsibility to respond to problems with your system under theEnvironmental Protection Act 2017.

Tips and maintenance

All systems require regular servicing and attention, to ensure that they continue to operate safely.

• Check sludge level, pumps, alarms, disposal area and pipes often, at least once a year.
• Desludge (empty by pumping out) the tank at least every three years as stated in your permits, or sooner if needed. Please make sure you send Council a copy of the maintenance report from your contractor.
• Do not wash or disinfect tank after desludging.
• If you have an Aerated Wastewater Treatment System ( treatment plant), ensure you have it serviced at intervals required by the manufacturer. This is to be done by an accredited service agent and copies of the agent’s service reports need to be sent Council.
• Do not build over or disturb the system, including the effluent area.
• Do not drive over or allow livestock to disturb the effluent trenches.
• Do not cover any of the system with concrete or pavers.
• Keep tree roots, vehicles and farm animals away from pipes
• If there is an odour from your system, flush a cup of garden lime down the toilet each day until the odour is gone. If odour persists, seek professional advice.
• Limit the use of germicides, such as strong detergents, disinfectants, toilet cleaners or bleaches.
• Use soapy water to clean toilets and other fixtures.
• Use only detergents with low alkaline salts and chlorine levels.
• Do not flush sanitary napkins or disposable nappies down the system.
• Use a sink strainer to stop food scraps from going into your system.
• Do not use a garbage disposal unit.
• Minimise the amount of oil and fat that goes into the system.
• Fill the septic tank with water to reduce odours on start up and after desludging.
• Make sure only a suitably trained person works on your system.
• Get Council  approval before altering or adding to your system.
• Know where your septic tank, pits, trenches and pipes are.
• Pump out the septic tank regularly.
• Have your treatment plant serviced at intervals required by the manufacturer.
• Use water efficiently by installing water-saving appliances and spreading out water usage to reduce overloading.
• Only flush or wash down items safe for your septic system. Do not flush down bleaches, fats, oils and sanitary products.

For renters

If you are a tenant of a rental property who is reliant on a on-site wastewater management system, be sure to contact your property manager should you have any concerns regarding the system.

Before constructing, installing, altering, amending, transferred or using any on-site wastewater management system (septic tank system) a permit must be obtained from Council.

 Proposed On-site wastewater management systems to are required to:

• Have a JAS-ANZ (Joint Accreditation System of Australia and New Zealand) Certificate of Conformity,
• Have a design or actual flow rate of sewage not exceeding 5000L on any day
• Comply with Planning Permits and Planning controls
• Be designed by a suitably qualified Land Capability Consultant, of whom will provide a Land Capability Assessment Report that
  
  Considers:

              *The best practicable and most sustainable on-site wastewater management system design capable of treating and retaining wastewater                    that does not pose an unacceptable risk of harm to the environment and human health.

              *The property on-site wastewater management system Land Capability Hazard Classification, available on Council's Interactive Map

              *Relevant geographical, social, standards, codes and legislative information when designing the altered or new on-site wastewater.

               *Whether primary, secondary or advanced secondary wastewater treatment is suitable for the site and situation.

Comply with: 

           *Environmental Protection Act 2017

           *Environmental Protection Regulation 2021

           *MAV Victorian Land Capability Assessment Framework 2014

           *EPA Victoria Guideline for onsite wastewater management 2024

           *EPA Victoria Guideline for onsite wastewater effluent dispersal and recycling systems 2024

           *Southern Grampians Shire Domestic Wastewater Management Plan 2019

In unsewered areas, Building Surveyors cannot issue a Building Permit until On-site Wastewater Management Permit has been issued by Council.

Where reticulated sewerage is unavailable, an on-site wastewater management system permit application is required to be submitted, not limited to:

• Constructing, renovating or extending an additional building.
• Changing the building and/or property use
• Constructing an additional bedroom or study or hobby room.
• Alteration or/and construction and/and Installation of wastewater plumbing fixtures such as bathroom, kitchen and laundry facilities i.e. toilet, basin, shower & sink 

An On-site wastewater Management System Permit is required to be approved by Council’s Environmental Health Department as per Environmental Protection Act 2017, and Environmental Protection Regulation 2021, prior to:

• Installation, replacement or relocation of internal plumbing, fixtures or fittings.

            and/or

• Change the design or construction of the onsite wastewater management system.

            and/or

• Premises wastewater hydraulic flow or organic load of the system is changed.

Council has 42 business days to determine an on-site wastewater management system permit application assessment after receiving all required documentation specified in theOnsite Wastewater Management System Permit to Install application, per Environmental Protection Act 2017,) and Environmental Protection Regulation 2021. However, Council works towards determining On-site Wastewater Management System Permit applications sooner than this.

Council’s Environmental Health Officers will inspect the property prior to the system being constructed, installed, altered, amended or transferred and following installation to ensure the on-site wastewater management system meets the guidelines and Environmental Protection Act 2017. If your property access is restricted, please contact the Environmental Health Department to make arrangements to enable Council Officers to undertake the appropriate inspections.

Once the on-site wastewater management system is installed or altered, you will need to submit as installed system layout plans with Plumbing Compliance Certificate to Council's Environmental Health Department.

The following weblinks and the following information to assist with understanding the requirements for owners and occupiers of land with an onsite wastewater management system including operating, maintaining, altering, installing a system.

• How to manage your own onsite wastewater system

• Guidance for owners  & occupiers of land with an OSWMS ≤ 5000 Litres on any day (including septic tank systems).

• Requirements for owners and occupiers of land with an onsite waster wastewater management system.

• Southern-Grampians-Shire-Council-Domestic-Wastewater-Management-Plan-2019.pdf(PDF, 5MB)
  
  

•  EPA Victoria Guideline for onsite wastewater management 2024

•  EPA Victoria Guideline for onsite wastewater effluent dispersal and recycling systems 2024

•  MAV Victorian Land Capability Assessment Framework 2014

• Constructing, Installing or Altering Onsite Wastewater Management System Application 

A septic system / onsite wastewater management system is a system that treats ‘black water’ (toilet waste), ‘greywater’ (wastewater generated by showers, baths, handwash basins, laundry, or kitchens), or ‘sewage’ (a combination of black and grey water).

Untreated (or inadequately treated) wastewater has long been recognised as posing a serious threat to public health.  Wastewater may contain disease causing pathogens (viruses, bacteria, and parasites), chemicals, and other contaminants from household, industrial or commercial activities.

Many of these substances can cause disease when ingested by humans so prevention of contamination of food and water supplies with sewage or blackwater is critical to preventing disease of both individuals and entire communities.  This is especially important in our water catchments areas, where leaking or failing systems can potentially contaminate the water we use for drinking.

The discharge of untreated or poorly treated wastewater into either surface or ground water also has the potential to seriously impact our environment, with impacts on both plant and animal species.  The delicate ecological balance can be damaged due to increased levels of nitrogen and phosphorus, and exposure to chemicals and pathogens.

Every member of our community has a responsibility to reduce the risk of their activities harming the environment or human health – so everyone who owns or uses one of these systems needs to do their part to ensure that the systems continue to work as intended, and any issues that are noted are seen to quickly.  

On-site wastewater management systems (often referred to as septic system) take wastewater and sewerage generated in homes and businesses and treats it so that it can be safely dispersed into the environment.  It does this through a combination of primary and secondary treatment.  The system can be thought of as a complex living ecosystem where bacteria are actively digesting the waste.

Most onsite systems consist of a large watertight tank which is usually buried in the ground.  Solid and liquid wastes from the household flow into the tank where they settle and separate into three layers:

• The heavier solid matter falls to the bottom of the tank (called sludge)
• The fat, oils and greases rise to the top (called scum)
• The remaining liquid effluent in the middle (called effluent)

As the waste separates, bacteria within the tank work to breakdown the wastes.  The tank needs to be large enough to hold all the wastewater generated by the household in a day, so that there is sufficient time for the settling to occur, and so that the tank does not overflow.

This is called the ‘Primary treatment’ stage.  The wastewater still contains dissolved pollutants and pathogens such as viruses, bacteria, and parasites.

From the tank, the liquid portion flows out of the tank.  There are several options for disposal of this effluent, each allowing for further breakdown and treatment of the wastewater.

Some systems discharge the effluent directly into the soil through an ‘absorption field’ made up of pipes or trenches.  Natural soil processes break down the waste further and kill off some of the nasty pathogens.  Eventually the effluent evaporates, is taken up by plants, or enters the groundwater.

Newer systems may ‘process’ the effluent further prior to dispersing it into an absorption field.  Called ‘Secondary treatment’.  Effluent may be filtered through a sand filter or media or moved through a second tank where it is aerated and mixed then then effluent maybe ‘disinfected’ using chlorine or ultraviolet light to reduce pathogens levels further.