1. Home
  2. Environment
  3. Onsite Sewage Management Systems

Onsite Sewage Management Systems

If your home is not connected to Council’s municipal sewerage system, you may have an On-Site Sewage Management (OSSM) system, such as a septic tank, composting toilet or aerated system. 

There are special regulations that apply to these systems. As the owner of the property, it is your responsibility to ensure that the system is registered and approved by Council and that it is working safely and effectively.

On-site systems can create a risk to health and the environment if not properly maintained. 



What is domestic waste water?

Domestic wastewater is generated from domestic sources such as:

  • Kitchen
  • Bathroom (sink, bath, shower)
  • Toilet
  • Laundry (washing machine, sink)

Within this are two types of wastewater – blackwater and greywater. Blackwater is human excreta and water grossly contaminated with human excreta. Greywater may still be contaminated with human excreta to a small degree. It includes kitchen, bath, shower, and laundry wastes.

An on-site system is a miniature sewage treatment plant. If it is misused, overworked, or incorrectly maintained it will fail. A system that is working will have an active bacteria culture. This breaks the sewage down through metabolic activities. Once the water leaves the system it is further purified by soil micro-organisms.

Problems can arise with these systems. Beneficial bacteria can be killed and soil absorption/filtration capabilities can be degraded over time. These problems combined with unsafe disposal activities can result in serious public and environmental health risks.



Registration and approval

Before installing a septic tank (or on-site sewage management system), you must first obtain approval from Council. This can be completed via the NSW Planning Portal, either in addition to a Development Application or as a standalone application.

If you live on a property that already has a septic tank (or on-site sewage management system), please ensure that it is registered with Council and has a current Approval to Operate. This is a requirement under the Local Government Act 1993 and there are penalties of up to $2,200 for failure to comply. You can check whether or not your system has approval by contacting Council’s Environment department.

Registrations for existing sewage management systems may also be completed via the NSW Planning Portal or by completing this form.

Fees and charges may apply. View fees and charges relevant to registration and approval of on-site sewage management systems.

Water Saving Tips

The minimisation of wastewater is important:

  • To prevent overload to the installed wastewater treatment device
  • To conserve water as a valuable resource
  • Can also save you money into the future in savings on your water bill

The following can assist in conserving water:

  • Dual flush cisterns
  • Water conserving shower heads
  • Water conserving dishwashers
  • Water conserving washing machines

For each of these products, the higher the WELS or AAAAA rating the more efficient the system.

Other water conserving strategies include

  • Taking shorter showers
  • Turning off the tap while cleaning your teeth
  • Fixing dripping taps
  • Use dishwashers and washing machines only when there is a full load

Unsafe Discharges

Some materials must not enter your septic system, otherwise problems will almost certainly arise.  These include

  • Stormwater from downpipes or rainwater tank overflows
  • Backwash water from pools or spa pools
  • Solid materials such as paper (depending on the system), plastic, sanitary napkins, tampons, nappies or nappy liners
  • Trade waste from commercial or industrial premises
  • Paint, petroleum products or other solvents, strong alkaline, acid or bleaching agents
  • Antibiotics and some other prescription medicines.


Which septic system is right for you?

  • There are various septic systems available, and it may be worth speaking with a Building Officer at Council or an Environmental Consultant before making a decision on what to buy.

    Factors that will influence which system you install include

    • Where the system will be located – soil type, the slope of the ground, available area for dispersal, proximity to bodies of water, etc
    • What the system will be used for – waste from toilets only with separate grey-water facilities or for all waste-water, whether or not the intention is to use treated waste-water for any form of irrigation, etc
    • Who will use the system – how many people is the residence capable of housing, how often is the premises occupied, etc
    • Water supply – is the residence connected to reticulated water, tank-water, bore-water, etc

    The most commonly used setup in Australia is the basic septic tank and trench system. This can be expanded to include sand filters, wetland treatment areas, and evapotranspiration beds, instead of the trench(es) where soil conditions make trenches less suitable.

    Aerated Wastewater Treatment Systems are also available, including a second tank that treats the effluent further through aeration and the use of chlorination or ultra-violet light before being pumped to an irrigation area. These systems are required to have a strict quarterly servicing contract and need to be closely monitored and maintained.

    Composting systems, both wet and waterless, are also becoming increasingly popular. As with any on-site sewage management system, it is important to make sure that what you purchase is accredited by the NSW Department of Health.

    For more information on which system will meet your needs you can refer to The Easy Septic Guide or speak with qualified plumber/septic system specialist or a Building Officer at Council.


Reporting a malfunctioning septic tank / wastewater system

If you are concerned that an on-site sewage management system is being operated in an unsafe manner or in a way which is detrimental to the environment, you can lodge a complaint with Council’s Customer Service Team for investigation by our Environmental Health Officers.

Please note that Council’s role is to implement the relevant environment and public health laws and does not extend to seeking compensation for any personal injury or to providing legal advice.

When lodging a complaint, please provide as much information as possible. 

If you have been exposed to a malfunctioning on-site sewage management system and you are feeling unwell or your health is affected in any way, it is important that you seek medical advice from your GP or local public health unit as soon as possible.

Public Health Unit
(Nepean Blue Mountains LHD)
(02) 4734 2022
After hours: 
(02) 4734 2000 (Nepean Hospital) ask for Public Health On call Officer.



Frequently Asked Questions

What is an aerated wastewater treatment system?
AWTS treat wastewater to a higher level than septic systems through an aeration process, clarification, and finally disinfection through chlorination or exposure to ultra violet light. It is important to have these systems regularly serviced to ensure pumps, air blowers, and other mechanical components are operating correctly and to replace chlorine tablets or to clean the ultra violet lamp. For systems that are used infrequently (such as holiday homes) it is very important that servicing occurs as your service technician may need to “feed” the system to ensure it operates effectively. These systems are commonly referred to as their brand names such as Envirocycle, Biocycle, and Bioseptic etc.
Why do I need warning signs and need to keep humans and animals away from the irrigated wastewater?

Legislation requires signage for safety reasons so as to ensure people are prevented from coming in contact with wastewater.

What is an “approval to operate”?

Operating a system of sewage management is a prescribed activity under section 68A of the Local Government Act 1993 and Subdivisions 6 & 7 of the Local Government (General) Regulation 2021. This means that an Approval to Operate a system of sewage management must be obtained from the local council.

Approval to Operate a system of sewage management requires the landowner to take all reasonable steps to minimise transmission of disease, pollution of water and degradation of land as a result of sewage management activity and requires that the landowner inform the Council about those activities and pay fees to contribute to the Council’s costs of managing the cumulative impact of sewage pollution.

Why should on-site sewage system owners have to pay council for an approval?

Most of the costs of operating an on-site sewage management system are borne by the landowner or resident, but the Council is responsible for supervision and environmental management. Residents in sewered areas pay for supervision and environmental management through sewerage charges, which include load based EPA licence fees and other environmental management costs. The inspection and monitoring regime conducted by Council’s Environmental Health Officers provides monitoring and assurance of water quality, better control of effluent discharge, supervision of plumbers and service agents, education programs and practical support to assist landowners.

Is Council approval required for existing systems?

Landowners with any type of on-site sewage management system are required to obtain a council Approval to Operate. Councils are entitled to charge a fee to cover the cost of registration and assessment. Please refer to Council’s Onsite Sewage Management Policy for further information on requirements.

What will Council do if it does not receive a service report?

Council will send a letter reminding the resident of the need to have the system serviced. If a service report is not received, a penalty infringement notice for $330.00 may be issued. It must be noted that it is the responsibility of the owner or licence holder to ensure that the service technician provides council with a service report. This is particularly relevant after the first letter has been sent.

What would Council do if they found a person discharging wastewater directly into a creek, bushland, or a stormwater service, or other water body?

These are offences under the Protection of the Environment Operations Act 1997 for pollution of water or land. Council would consider a prosecution or issuing penalty infringement notice (fine). On-the-spot fines for such offences are $4000 for individuals or $8000 for corporations.

Will council be inspecting my AWTS?

Council will be randomly inspecting AWTS within the local government area. This is to ensure that the service technicians are servicing systems within the Local Government Area to a satisfactory standard. Council must receive quarterly service reports from service technicians and will be monitoring this through the database system. It is your responsibility to ensure your service technician is forwarding your service report to Council. If these reports are not received, Council may issue you with a penalty infringement notice (fine).

Further information

Onsite Sewage Management Strategy

This Management Strategy has been developed to help Lithgow City Council assess, regulate and manage the selection, design, installation, operation and maintenance of on-site sewage management systems.

The easy septic guide

If your home is not connected to the sewer, this booklet is for you.

On-site Sewage Management For Single Households

A guide to effective management of domestic sewage and wastewater