education.vic.gov.au

Wastewater Treatment Systems

Including septic tanks and treatment systems for wastewater

Policy last updated

10 January 2023

Scope

  • Schools

Date:
January 2020

Policy

Policy

This policy sets out the actions that schools with an on-site wastewater management system must take to maintain their system and minimise potential health and environmental pollution risks to students, staff, and neighbouring properties.

Summary

  • In unsewered areas, an on-site wastewater management system is required to receive and treat wastewater from kitchens, toilets, bathrooms and laundries. The capacity and type of system required will depend on the maximum number of students and staff in the school as well as the land conditions.
  • An on-site wastewater management system requires a council permit (system below 5,000 litres per day) or an Environment Protection Authority (EPA) licence for (systems above 5,000 litres per day).
  • Permits and licences document the regular inspection and maintenance activities required to keep on-site wastewater systems operating correctly and to prevent pollution. Schools must ensure these activities are undertaken at the required frequency, with inspections to occur at least annually.
  • Schools should familiarise themselves with the type of system in place, the system’s location, its performance, the potential risks, and any ongoing management activities required by the system’s Local Government Authority (LGA) permit or EPA licence.
  • Schools must ensure system inspections and maintenance activities are documented and recorded in the Asset Information Management System (AIMS), with records kept for at least 2 years.

Details

On-site wastewater management systems (OWMS) are necessary for schools not connected to a mains sewer. OWMS include septic tanks, composting toilets, and secondary treatment plants to treat, recycle or dispose of wastewater produced from toilets, bathrooms, kitchens, and laundries. Correctly maintained and operated OWMS protect the health of the school community and minimise the risk of environmental pollution.

Schools with OWMS are required to maintain and operate their systems in line with the 3 sections of this policy: identify, manage and monitor. Schools are expected to meet the costs of these activities using their student resource package funding.

The Buildings and Grounds Maintenance and Compliance Policy sets out the department’s compliance and monitoring process that applies to all key asset management activities, including management of OWMS.

Identify

As a first step, schools with OWMS must familiarise themselves with the type of system in place, the system’s location, its performance, the potential risks, and the ongoing maintenance program required. Refer to the risks and hazards chapter of the Guidance tab for more information about the risks associated with improperly maintained OWMS, including measures schools must take to minimise these risks. Refer to the system types chapter of the Guidance tab for more information about the different types of OWMS.

Schools must have valid, unexpired permits or licences for their systems. Licences and permits identify the regular maintenance and inspection activities needed to ensure that a system is safe and operational.

  • For systems that can treat up to 5,000 litres per day, schools should refer to their OWMS permit issued by their LGA for information regarding the management of their system.
  • For systems that can treat above 5,000 litres per day, schools should refer to their OWMS EPA license for information regarding the management of their system.

Schools without permits or licenses should contact their local council to determine whether an EPA licence is required. Some LGAs may impose additional compliance requirements. Schools can find out more by referring to the permits and licences chapter of the Guidance tab or by contacting their local council.

Manage

Schools must manage their systems through regular inspection, maintenance, and management, as required in their permits or licences. Additionally, schools must notify their local council of any system defects, and rectify any faults detected during regular system inspections.

To maintain system performance, schools must arrange servicing at the frequency specified in the LGA permit or EPA licence. Servicing must be undertaken by a VBA registered plumber or equivalent. OWMS manufacturers or suppliers of wastewater treatment plant are also permitted to service and maintain the system.

Refer to the routine maintenance chapter of the Guidance tab for further information on inspection, maintenance, water testing and treatment activities.

Monitor

Schools must routinely monitor their systems by arranging regular inspections as specified in their licences or permits. Inspections must be undertaken by a VBA registered plumber or equivalent. Registered plumbers prepare a service report upon completion of inspections and maintenance activities, and the report must include the following information:

  • the operating condition of the system (including confirmation that the system load and capacity is fit for purpose and within design limits)
  • the maintenance that was performed
  • the percentage of scum and sludge in the primary settlement tank
  • any remedial work that was completed at the time of service
  • any remedial work that is required and which the school needs to carry out.

Schools must notify their local council of defects that have not been corrected to minimise the impact of possible wastewater seepage on adjacent properties and lands. Some councils require maintenance reports to also be sent to them following each service. Schools can refer to their permits or licences to confirm exact LGA requirements. Refer to the emergency management chapter and defects chapter for information about responding to faults and failures associated with an OWMS.

The Victorian School Building Authority (VSBA) monitors compliance of mandatory maintenance requirements (using AIMS where possible) and responds to non-compliance by providing direct support to schools. At a system level, the VSBA provides guidance and support through revision of policies and procedures. Refer to the support for schools chapter for more information about the support VSBA provides to schools, including contact details.

Relevant legislation


Guidance

Guidance for on-site wastewater management systems

This guidance contains the following chapters, which can be accessed using the menu bar:

  • Risks and hazards
  • System types
  • Disposal methods
  • Permits and licences
  • Routine maintenance
  • New system installations, replacements and decommissioning
  • Emergency management
  • Defects
  • Support for schools

Risks and hazards

Risks and hazards

Overview

To ensure their systems are managed safely, schools need to be aware of the risks associated with their installed on-site wastewater management systems (OWMS).

A poorly installed or maintained OWMS system can be a risk to human health and the environment. This is especially true of older systems. The risks can include:

  • adverse impact on human health
  • polluted drinking water
  • land and waterway contamination
  • offensive smells.

Preventative measures such as routine maintenance can reduce the risks and hazards associated with an OWMS. These measures are outlined below.

Wastewater overflow risks and hazards

Contact with wastewater can occur when effluent or untreated wastewater overflows or is improperly discharged, resulting in seepage onto the property. The common cause of on-site wastewater overflows is the failure, or inadequate maintenance and servicing of the OWMS.

Wastewater contains dissolved and suspended biological matter that can contain many microorganisms that may be harmful to humans, animals, and the environment. These microorganisms can include viruses, bacteria, protozoa, fungus, and parasitic organisms.

Contact with wastewater or its products can expose people to harmful microorganisms that can cause illnesses such as:

  • gastroenteritis (diarrhoea or vomiting)
  • giardiasis and cryptosporidiosis (severe stomach cramps, diarrhoea, or vomiting)
  • viral infections such as hepatitis (liver infections)
  • infections of the skin or eyes.

Risk warning signs

Schools must monitor their systems for potential failures, especially in older systems. Some early warning signs of a potential failure including:

  • foul smells coming from or near the system
  • slow running toilets or drains
  • full or blocked grease trap
  • wastewater runoff from the disposal area
  • wastewater pooling on the disposal field's surface.

Schools must take steps to address any issues as soon as possible.

Refer to the emergency management chapter and defects chapter for further information on managing system failures.

Minimising risks associated with on-site wastewater management systems

Schools must take practical and preventative measures to minimise the risks posed by OWMS such as:

  • ensuring system can be accessed easily
  • when signs of system failure are identified, use a Victorian Building Authority (VBA) registered plumber to assess whether a system needs cleaning and unblocking – refer to the section on risk warning signs above
  • desludging the system every 3 years or once deemed required following inspection by a VBA registered plumber or equivalent (how often depends on the level of system use)
  • taking all reasonable steps to ensure the system is maintained properly and keeping all system maintenance records
  • having an Environment Protection Authority (EPA) accredited waste management consigner install an alarm and flow meter to warn of breakdowns to critical operating components such as pumps
  • arranging the maintenance of the disinfection chamber (if any) – this chamber uses chlorine to disinfect the treated water, and chlorine tablets must be fitted to the dispenser in the right way
  • for disinfection chambers fitted with UV disinfection, UV light tubes must be cleaned quarterly by a VBA registered plumber or equivalent
  • not driving vehicles over any part of the system
  • not allowing stormwater to discharge into the on-site system or over the disposal/drain field
  • not obstructing or covering the tank or drain field
  • not placing non-biodegradable items or rubbish into the system – bacteria and other organisms are unable to break down these items or rubbish
  • ensuring that Local Government Authority or EPA maintenance requirements are followed as per the issued permits and licences.

System types

System types

Overview

On-site wastewater management systems (OWMS) are available in various designs, each using multiple chambers and mechanisms for the treatment of wastewater to produce site-specific effluent (treated wastewater) tailored to the quality required for its local disposal or final use. The 2 main types of systems are:

  • primary simple systems which are comprised of only septic tank/s with no secondary treatment for sub-surface disposal only
  • secondary complex systems which are comprised of settling chamber with secondary treatment/s (UV, chlorine, mechanical filters, and so on) for surface irrigation or sub-surface disposal only.

An OWMS collects, settles and treats wastewater to remove scum, organic matter, nutrients, pathogens, and grease. Solids are separated from wastewater and settle at the bottom of the tank to be decomposed by bacteria or pumped out by desludging.

The water that remains after solid waste is separated from wastewater is called effluent. Effluent must be disposed of or have an end-use. The quality of effluent varies depending on the level of treatment it has received, and its quality determines how it can be disposed of or used.

To create effluent, wastewater is first passed through a settling chamber where heavier solids settle and form a semi-liquid sludge mass at the bottom of the tank. Solids that float, such as oils and greases, rise to the top.

Separated from the solid wastes is the effluent water left in the middle. The bacteria present in the waste will naturally decompose solids in the tank, but over time the solids (sludge) will settle at the bottom of the tank and need to be periodically removed by emptying (desludging) the tank. A system will fail to work safely if the sludge accumulates

Refer to the routine maintenance chapter for further information on desludging requirements.

Primary systems – simple (septic tank/s only, no secondary treatment)

Simple systems (otherwise known as primary systems) rely on flotation and settlement to separate solids from liquids for the disposal of the clarified but still contaminated effluent water (treated to primary quality) from septic tanks and composting toilets.

Wastewater treated to primary quality is only suitable for disposal and release below ground via soil absorption trenches, mounds and evapotranspiration beds or trenches.

It is important for schools to know what quality of effluent their system is designed to produce, as stated in their permit, to ensure the correct disposal or end use occurs.

Refer to the disposal methods chapter for further information on disposal methods and treatments.

Secondary systems – complex (solid separation with secondary treatment)

Complex systems rely on solid separation combined with a secondary treatment system (STS) to clean and treat the effluent so that it can be used for irrigation (treated to secondary quality).

A secondary system typically consists of multiple chambers or mechanical components that provide additional aeration, filtration and disinfection. Filters are used to break down and remove solid contaminants, while chlorine or ultraviolet light (UV) is used to disinfect effluent.

These systems produce higher quality treated effluent that can be recycled for surface irrigation purposes. Where approved, wastewater treated to secondary quality can also be dispersed to land via subsurface irrigation.

It is important for schools to know what quality of effluent their system is designed to produce to ensure the correct disposal or end use occurs.

Schools are not permitted to use greywater for internal re-use (toilet flushing, washing machine). External re-use of greywater for watering gardens via dedicated purple taps and hoses is also not permitted at any school premise using OWMS.

Refer to the disposal methods chapter for more information about disposal methods and treatments.

Common treatment methods

Primary and secondary OWMS use various treatment methods and combinations of treatment systems designed to treat and manage wastewater. These include:

  • biofiltration – uses sand filters, contact filters or trickling filters to ensure that any additional organic matter/sediment is removed from the wastewater
  • aeration – a biological process where organic matter is decomposed by bacteria using oxygen saturation by introducing air to wastewater. Typically, the aeration process can last for a few hours and is very effective
  • oxidation ponds – typically used in warmer climates, this method utilises constructed ponds/lagoons, allowing wastewater to pass through for a set period before being retained for 2 to 3 weeks
  • disinfection – uses ultraviolet light (UV) or chlorine.

Disposal methods

Disposal methods

Effluent can be disposed of either by below ground absorption or by reusing it for irrigation. The disposal method used depends on how much treatment the wastewater has received.

Wastewater treated to primary quality is only suitable for disposal below ground via soil absorption trenches, mounds and evapotranspiration beds or trenches.

Wastewater treated to secondary quality can be dispersed to land via:

  • pressure-compensating subsurface irrigation
  • surface irrigation using a network of drip, trickle or spray points to apply effluent just above the ground's surface
  • subsurface irrigation using a network of polyethylene pipes located just under the ground's surface to apply disinfected effluent in the root zone of plants, preventing airborne drift and minimising runoff
  • sand mounds above the soil surface, which can be used when typical disposal methods are unavailable
  • absorption trenches and beds, which can be used to release effluent below the surface through narrow and deep trenches, or wide and shallow beds
  • evapotranspiration absorption beds that remove water from land covered by vegetation through evaporation.

Permits and licences

Permits and licences

To operate, install a brand-new system or modify an existing one (including changes that increase system flow or load), permits from the Local Government Authority (LGA) or permission licences from the Environment Protection Authority (EPA) are required depending on the system daily capacity load.

  • LGA permits and certifications are required for systems capable of processing up to 5,000 litres per day.
  • EPA development licences are required for systems above 5,000 litres per day. Please contact EPA via permissions@epa.vic.gov.au to enquire whether you will require an A14 Permit for systems above 5,000 litres per day.

Documents such as permits, certificates, and licenses must be uploaded into the Asset Information Management System (AIMS) school documents section or retained in the school's file records until AIMS is available.

LGA permits and certificates

For systems that can treat up to 5,000 litres of wastewater a day, schools must apply for a permit from their LGA to construct, install or alter an OWMS.

On completion of construction, installation or alteration of an OWMS, the LGA who issued the permit inspects the system. If the LGA is satisfied the system complies with the permit, they issue a certificate approving the use of the system.

A certificate-to-use confirms the compliant installation of a new or modified system. Permits outline the ongoing preventative measures, routine maintenance and other compliance requirements that a school must conduct.

Schools without an active permit, schools undertaking new installations or schools altering existing systems must contact their LGA to be issued with a certificate-to-use and permit.

A wastewater consultant or Victorian Building Authority (VBA) registered plumber may be needed by schools to assist in the process of gathering and submitting all the required information to obtain a permit or certificate. The LGA may refuse to issue permits for systems that do not conform to relevant operational standards.

Permits expire after 2 years from the date of issue and schools must regularly review their permits.

EPA licences

Systems that can treat more than 5,000 litres per day need an EPA licence for their installation and use. Schools will need to obtain an EPA development licence and an operating licence unless exemptions apply.

There are 2 EPA licences that may apply to schools with OWMS. The first is a development licence which is needed to install or modify a system. The second is an operating licence which is needed to use a system.

Operating licences outline the risk management steps that a school must take on the operation and maintenance of OWMS.

Schools may consider engaging a wastewater consultant or VBA registered plumber to assist in the process of gathering and submitting all the required information to obtain EPA licences.

EPA development licences

EPA development licenses are for the design, construction and modification stages of building projects for industrial or waste management activities that are high-risk. This includes school OWMS that can treat more than 5,000 litres per day.

By default, works approvals become development licences. If you have a current works approval, this will immediately become a development licence under the Environment Protection Act 2017 (Vic). However, the conditions of your new operating licence will change. You can review the conditions by type of licensed operating activity.

Schools can apply for a development licence onlineExternal Link and will need to create an EPA Portal accountExternal Link . For more application support, refer to how to apply for a licenceExternal Link .

Schools will need to next apply for an operating licence once they have obtained a development licence.

EPA operating licences

EPA operating licences are for complex high-risk industrial and waste activities that are ongoing. This includes school OWMS that can treat more than 5,000 litres per day. These licences expire after 20 years.

Without having a previous development licence, schools can go directly to an operating licence only when:

  • the school is currently operating a facility that requires an operating licence, under the Environment Protection Regulations
  • an operating licence is due to expire, and a school is re-applying for the same activity, at the same activity address.

Schools can apply for an operating licence onlineExternal Link and will need to create an EPA Portal accountExternal Link . For more application support, refer to how to apply for a licenceExternal Link .


Routine maintenance

Routine maintenance

Schools manage their inspection and maintenance activities by first familiarising themselves with their system and referring to their permits or licences. The Environment Protection Regulations 2021 (Vic) provide more specific requirements for the management of on-site wastewater management systems (OWMS) with flow rates not exceeding 5,000 litres on any day, including older legacy systems.

Under the Regulations, schools with OWMS must take reasonable steps to:

  • operate the system so it does not pose a risk to human health or the environment
  • maintain the system in good working order, including older legacy systems that may not meet current standards
  • check for signs the system may be failing or is not in good working order
  • respond to any system failures.

Permits and licences identify the system specific inspection and maintenance activities that are necessary to ensure the OWMS is safe for use. Refer to the permits and licenses chapter for further information.

Schools use the Asset Information Management System (AIMS) to manage their OWMS maintenance and preventative measures by activating their annual contracts OWMS routine maintenance tasks. Activation of routine maintenance tasks in AIMS automates the creation of reoccurring work orders that are used to manage on-site wastewater systems.

The routine maintenance tasks available for school use in AIMS are:

  • AC2.1 – On-site Wastewater Management Systems – Septic Tank (Annually)
  • AC2.2 – On-site Wastewater Management Systems – Tank and Treatment (Quarterly)
  • AC2.3 – On-site Wastewater Management Systems – Emptying/Desludge.

A school will only need to activate either AC2.1 or AC2.2. All schools with OWMS must activate AC2.3. The Environment Protection Regulations 2021 (Vic) also require schools to:

  • keep maintenance service records and provide them to their local council on request
  • provide information to occupiers on how to correctly operate and maintain the system
  • notify their local council of signs of failure or that the system is not in good working order.

Additionally, schools must ensure that system inspection reports, water quality testing results (if required), LGA defect notifications, and maintenance activities are documented and recorded in AIMS, with records kept for a minimum of 2 years. Schools that are not yet using AIMS should continue to keep local records until AIMS is available.

If your school is yet to be inducted to AIMS, maintenance tasks should be scheduled into the school’s maintenance calendar.

Refer to the AIMS and OWMS quick reference guide on the Resources tab for more information on activating routine maintenance tasks and record keeping in AIMS.

Inspection and maintenance activities

Schools must undertake regular inspection and maintenance activities to keep their OWMS safe for use. This means annually for primary systems and quarterly for secondary systems. Schools must:

  • review permits and licenses to ensure they are valid and not expired
  • inspect the conditions of septic tanks and treatment plants
  • inspect drainage for evidence of blockages/overflow
  • inspect the conditions of distribution pit/s and absorption trenches/fields
  • inspect tank covers and screens to ensure they are intact
  • take flow meter reading (if installed)
  • check and confirm system allowances (system type and size) are still fit-for-purpose based on school population size (loading)
  • check sludge levels
  • perform tests and checks as per EPA 891.4 or equivalent (that is, biochemical oxygen demand (BOD), E.coli, suspended solids) and take action if required
  • identify defects, provide defect notification to LGA, and keep record of notification
  • schedule and arrange desludging (every 3 years) or when required using an EPA accredited waste management consigner.

Inspection and maintenance works should be carried out by a Victorian Building Authority (VBA) registered plumber or suitably experienced service providers, depending on the works required.

Schools are required to keep records of system maintenance, inspections, and water quality test results for at least 2 years.

Desludging/pump out

To keep your septic system treating sewage efficiently, the tank needs to be pumped every 3 years or once deemed required by inspection by an EPA accredited waste management consigner. The pumping-out/desludging is to be conducted by an EPA accredited waste management consigner specialised with on-site wastewater management systems. More information about accredited waste consigners is available on the EPA websiteExternal Link .

The bottom of the septic tank accumulates sludge as the septic system is used. Tank efficiency reduces with an increasing sludge level and solids are more likely to escape into the absorption area. When sludge accumulates too long there is no settling, causing sewage to go directly to the soil absorption area. This results in less sewage being treated.

It is important to know that the soil absorption field will not malfunction immediately if a tank is not pumped out. However, the septic tank is no longer protecting the soil absorption field from solids.

It is possible that the soil in the absorption field will need to be replaced if the tank is neglected for a long time.

After pumping out, tanks must not be washed out or disinfected. They should be refilled with water to reduce odours and ensure stability of plumbing fixtures. A small residue of sludge will always remain and will assist in the immediate re-establishment of bacterial action in the tank.

Schools should keep a record of their septic tank pump-outs and notify the local council that a pump-out was undertaken in accordance with the council permit.

Treatment testing

For complex secondary systems, effluent quality tests (to be carried out by a qualified plumbing or wastewater engineer), are required at the frequency required by the permit or licence to ensure the treatment plant is performing within limits. Performance limits depend on the effluent end use.

  • Primary simple systems do not have a specific water quality standard.
  • For effluent disposed by surface irrigation, the EPA advanced secondary effluent standard (10/10/10) applies. Samples are to be analysed for:
    • biochemical oxygen demand (BOD) – less than 10mg/L BOD
    • total suspended solids (TSS) – less than 10mg/L TSS
    • E.coli bacteria – less than 10 Escherichia coli cfu/100.

Other analysis may need to be conducted depending on the system and treatments used such as chlorine analyses. Schools should refer to their LGA permit or EPA license for full water quality testing requirements.

Testing samples for analysis must be conducted to a laboratory accredited by the National Association of Testing Authorities (NATA).


New system installations, replacements and decommissioning

New system installations, replacements and decommissioning

Secondary treatment systems have a limited stated service with a typical lifespan of 15 years before needing replacement. Schools should check the stated service life of their prospective on-site wastewater treatment system (OWMS) and anticipate replacing it with a new system at that time or arrange for mains connection which may be the more cost-effective option.

The decision to install, replace or decommission an OWMS for a school must be made collaboratively with:

  • the relevant regional office
  • the Victorian School Building Authority (VSBA)
  • the school planning committee
  • the local council
  • the applicable water retailer.

A land capability assessment (LCA) is required for new system installation and upgrades. An LCA assesses the capability of a site to sustainably utilise and manage wastewater, and identifies the greatest risks to an area of land from wastewater management.

An LCA is required for most developments which do not have access to sewerage facilities, prior to the development proceeding. An LCA may also be required to determine whether an existing development can sustainably contain all treated wastewater on-site. Your school’s OWMS installer can determine whether an LCA is required.


Emergency management

Emergency management

The Victorian School Building Authority (VSBA) make-safe program assists schools that have sustained damage through an incident or event, where that damage presents an immediate health and safety concern for students, staff and/or the community.

Make-safe works eliminate the risk of immediate hazards resulting from the incident or event.

If your school needs emergency make-safe provisions, contact the VSBA make-safe service provider on 1300 133 468.

In the event of an incident or emergency that causes harm or creates risk of harm to a student or employee, schools are required to report the incident as per the steps outlined in the Managing and Reporting School Incidents (Including Emergencies) Policy.

Refer to the Buildings and Grounds Maintenance and Compliance Policy for more information on the make-safe program.


Defects

Defects

If there is a system defect, the local council must be notified electronically or in writing. The notification must contain information about how risks will be mitigated and how defects will be resolved. Schools should keep track of all LGA defect notifications and upload them into the Asset Information Management System (AIMS) as a compliance record.

An eduSafe Plus or ISOC report must also be generated if any defects are discovered in your school's on-site wastewater system, depending on the severity and impact of the defect. Refer to the Managing and Reporting School Incidents (Including Emergencies) Policy for more information about reporting and managing school incidents.

Additionally, it is a school’s responsibility to identify, record, and address system defects in AIMS to rectify the defects.


Support for schools

Support for schools

Annual Contracts team

The Victorian School Building Authority (VSBA) supports schools to meet their mandatory compliance obligations through the work of the School Asset Assessments Unit (SAAU) which supports schools with managing their annual contracts.

The VSBA Annual Contracts team has been established within SAAU to support schools directly with guidance and support and can be contacted at vsba.annual.contracts@education.vic.gov.au and 03 7022 5800.

Routine maintenance funding

Schools should fund their on-site wastewater management system (OWMS) responsibilities from their Student Resource Package (SRP) funding.

The annual contracts and essential safety measures funding line includes an allocation to schools for inspection and servicing of sewage and water treatments as specified under SRP Guide Reference 36.

The maintenance and minor works funding line is allocated to schools to meet costs associated with repairs and maintenance.

Maintenance items related to OWMS should be included in school maintenance plans.

Emergency maintenance funding

In some situations where a school has insufficient funds for critical repairs costing $5,000 or more, they may apply for assistance through the VSBA’s emergency maintenance program. For more information, refer to the Guidance tab of the Buildings and Grounds Maintenance and Compliance Policy.

Local Government Authorities

Schools are encouraged to contact their municipality health and environment officers who can provide OWMS support and advice.

Contract your local councilExternal Link for more information.

Environment Protection Authority

Schools may contact the Environment Protection Authority (EPA) on 1300 372 842 for OWMS advice.

Department of Health

Schools may contact the Department of Health on 1300 651 160 for support and advice to ensure that illness is not spread to the school community from an OWMS.


Resources

Resources

Guides

Useful websites


Reviewed 06 January 2023