On-Site Sewage Management (OSSM) Systems
On-site sewage management systems (such as septic tanks and AWTS) treat wastewater generated from households that are not connected to Council’s reticulated sewerage network.
These systems operate as small-scale sewage treatment plants and, when properly designed, installed and maintained, can effectively manage household wastewater.
However, if an on-site system is misused, overloaded, or poorly maintained, it can fail and lead to serious public health risks such as:
- Bacterial: Salmonella, E. coli, Shigella, diarrhoeal infections, trachoma
- Viral: Gastroenteritis, Hepatitis A
- Parasitic: Giardia, Cryptosporidium, dwarf tapeworm, threadworm, hookworm
- Insect and vermin infestations – Flies, mosquitoes and rodents can spread disease when they have access to untreated sewage.
- Water pollution – Contamination of groundwater, bore water and nearby creeks or rivers.
- Soil and vegetation damage – Degradation of soil quality and harm to plants, reducing land usability.
- Amenity impacts – Offensive odours, unsightly pooling and insect activity can all affect local amenity.
What is On-Site Sewage Management?
If your home is not connected to the reticulated sewerage system (the town sewer), it will have an OSSM system located on your property. This system collects, treats and disposes of all wastewater generated from your household within the boundaries of your land.
Common types of OSSM systems include:
• Septic tanks
• Aerated Wastewater Treatment Systems (AWTS)
• Holding tanks with pump-out services
• Wet composting toilets
• Greywater treatment systems
• Absorption trenches and evapotranspiration beds
• Irrigation areas (mound or subsurface)
Because on-site systems manage and dispose of wastewater entirely within the property, it is important that owners and occupants understand how to operate and maintain their system correctly. Proper management helps prevent health risks, environmental pollution, and nuisance issues such as odours or surface pooling.
Approvals
Approval to Install, Construct or Alter an OSSM System
Under Section 68 of the Local Government Act 1993, an Approval to Install, Construct or Alter an On-Site Sewage Management System is required.
Detailed plans and supporting information about the proposed system must be included with the application to ensure it meets relevant environmental and public health standards.
Approval to Operate an OSSM System
Under Section 68 of the Local Government Act 1993, an Approval to Operate an On-Site Sewage Management System is also required.
AlburyCity requires property owners to obtain this approval in the following situations:
- New systems – After final inspection by Council confirms that the system has been correctly installed and is operating as intended.
- Existing systems – Where a system has not previously undergone a final inspection, Council will carry out an inspection and risk assessment to determine its level of compliance and the potential impact on public health and the environment.
The duration of the approval will depend on the risk rating assigned to the system, with higher-risk systems generally requiring more frequent renewal and inspection.
It is an offence under the Local Government Act 1993 to install, construct, alter or operate an OSSM system without Council’s prior written approval. Non-compliance may result in enforcement action, including penalties.
How to Apply
Download and complete the application form below:
Application for Onsite Sewage Management System.PDF
Email your application and documentation to info@alburycity.nsw.gov.au Attention: Environmental Health
Or apply online via the NSW Planning Portal
For New Dwellings
When applying for an Approval to Install, Construct or Alter an OSSM System for a new dwelling, the following information must be submitted with the application (at a minimum):
- Site Constraints Plan – A scaled plan showing the proposed location of the OSSM System and the effluent land application area. The plan must clearly indicate all buffer distances to waterways, dams, buildings, driveways, swimming pools, water storage tanks and property boundaries.
- Floor Plan – Of any building connected to the OSSM system.
- Manufacturer’s Specifications – For the proposed OSSM System. Refer to NSW Health Accreditation of Sewage Management Facilities for further information.
- Land Capability Assessment (LCA) Report – Prepared by a suitably qualified person in accordance with AS/NZS 1547 and the NSW Environment & Health Protection Guidelines.
- Operation and Maintenance Details – Information outlining how the system will be operated, maintained, and serviced to ensure ongoing performance.
Land Capability Assessment (LCA) Report
A Land Capability Assessment Report (LCA) is a technical document that evaluates a property’s ability to safely and sustainably manage wastewater on-site. It is usually prepared by a suitably qualified environmental scientist, engineer, or soil assessor and forms a key part of the approval process for OSSM Systems.
What is a Land Capability Assessment Report?
A LCA assesses how suitable a property is for the on-site treatment and disposal of wastewater. The report considers site conditions such as soil type, slope, vegetation, drainage, and proximity to water bodies to determine the most appropriate wastewater management system and land application method.
The purpose of the LCA is to ensure that the proposed OSSM system will:
- Protect public health and the environment;
- Prevent pollution of surface and groundwater;
- Ensure wastewater is effectively treated and absorbed within the property boundaries; and
- Provide for the long-term sustainable operation of the system.
What an LCA Includes
A comprehensive Land Capability Assessment Report generally includes:
- Site description – Location, size, slope, topography, vegetation and climate.
- Soil assessment – Soil type, texture, permeability and drainage characteristics (including results of percolation or infiltration testing).
- Hydrology and water features – Proximity to creeks, rivers, dams, bores, or groundwater.
- Risk assessment – Identification of potential risks to public health, surface water, groundwater, and the environment.
- System design recommendations – Type of on-site system suitable for the site (e.g. septic, AWTS, sand filter, mound system).
- Land application area design – Location, size and layout of disposal or irrigation areas, including buffers to sensitive features.
- Management and maintenance plan – Guidance on system upkeep to ensure long-term performance.
When an LCA is Required
A Land Capability Assessment Report is typically required when:
- A new OSSM system is proposed;
- A significant upgrade or alteration to an existing system is planned;
- The property is located near environmentally sensitive areas (e.g. waterways, wetlands, groundwater recharge zones); or
- The property is small or has physical constraints (e.g. steep slopes, poor soils, high water table).
Small Lot Considerations (Less than 2,000m²)
For properties smaller than 2,000m², applicants must demonstrate that the proposed system can be installed and operated without causing adverse impacts to the environment, public health, neighbouring properties, or sensitive receptors.
This justification must be prepared by a suitably qualified person and should demonstrate:
- Sufficient space for both primary and reserve disposal areas within the site boundaries.
- Where a reserve area cannot be accommodated, a higher level of wastewater treatment (secondary or advanced system) will be required.
- Consideration of alternating disposal areas (using an indexing valve) to allow resting periods and prevent oversaturation of the soil.
Inspections & Fees
Inspections
Council has a responsibility to monitor the performance of all existing OSSM systems and to take action where a system is found to be failing or posing a risk to public health or the environment.
To support this, Council has been implementing a risk-based inspection program. During this program, all systems will undergo an initial evaluation to determine their risk rating based on:
- System performance;
- Design and installation;
- Location and proximity to sensitive areas; and
- Local land features (e.g. soil type, slope, drainage).
Each system will then be inspected on an ongoing basis, with the frequency of inspection determined by its assigned risk level. The Approval to Operate will also be issued in accordance with the system’s risk rating.
| Risk Rating | Example Characteristics | Inspection Frequency |
|---|---|---|
| Low Risk | New or well-maintained systems, compliant design, suitable soils | Every 15 years |
| Medium Risk | Systems with minor issues, moderate constraints, or aging components | Every 10 years |
| High Risk | Poorly performing or non-compliant systems, sensitive locations | Every 5 years |
Fees
Owners of properties with an OSSM system are required to pay applicable fees to cover Council’s costs for assessment, inspection and regulatory oversight.
New Systems
Property owners will be charged a fee to obtain an Approval to Operate for their new OSSM system.
This fee covers:
- Assessment of the Application to Install or Alter an OSSM system;
- Issuing of the Approval to Install;
- Issuing of the Approval to Operate; and
- One compliant inspection of the OSSM system prior to backfilling.
The property owner will be invoiced this fee when the Approval to Install or Alter is issued.
Existing Systems
For existing systems, property owners will be charged an inspection fee.
This fee covers:
- The inspection of the OSSM system; and
- The issuing of an Approval to Operate following the inspection.
For details of current fees and charges, refer to AlburyCity's Fees and Charges or speak with the Environmental Health team.
Performance Standards
Under the Local Government (General) Regulation 2021, all OSSM systems must be operated and maintained in accordance with the following performance standards:
- Prevention of the spread of disease-causing micro-organisms;
- Prevention of foul odours;
- Prevention of water contamination;
- Prevention of soil and vegetation degradation;
- Discouragement of insects and vermin;
- Ensuring that persons are not exposed to untreated sewage or effluent during normal activities on the property; and
- Minimisation of adverse impacts on the amenity of the premises and surrounding land.
Council’s Role in Monitoring Compliance
Council officers use these performance standards to assess compliance when:
- Evaluating applications for new OSSM installations; and
- Inspecting existing systems as part of the ongoing risk-based monitoring program.
If an OSSM system fails to meet the required performance standards, it will be deemed a non-compliant or failed system. In such cases, the property owner will be required to carry out rectification works or system upgrades to ensure the system operates effectively and safely.
Council has several statutory enforcement options available under the Local Government Act 1993, including the issue of Notices, Orders, or Penalty Infringement Notices (on-the-spot fines) to achieve compliance.
Common Problems
Common problems identified with OSSM systems include:
- Excessive wastewater loading – Too much wastewater entering the system can cause effluent to flow too quickly through the septic tank, preventing bacteria from effectively treating the waste. Solids may then be pushed into the absorption trenches, causing blockages.
- Excess sludge and scum – Failing to have a septic tank de-sludged regularly leads to a build-up of solids, reducing treatment efficiency. This can result in untreated effluent and solids entering the absorption trenches, leading to system failure.
- Use of toxic chemicals – Harsh chemicals such as solvents, oils, paints, disinfectants, pesticides, household cleaners and bleaches can kill the beneficial bacteria that break down waste. This disrupts treatment and can cause pollution or damage to the disposal area.
Signs of a Failing System
Indicators that your OSSM system may be failing include:
- Water draining slowly from basins, sinks or showers;
- Gurgling noises from household drains;
- Sewage odours coming from drains, the tank or land application area;
- Water backing up into household fixtures or yard gullies; or
- Wastewater pooling or surfacing over the disposal area.
If any of these signs are present, contact a licensed plumber or an OSSM system service agent for assessment and repair.
Preventing Problems
Do:
- Learn how your sewage system operates, including its maintenance requirements.
- Know the location and layout of your tank and land application area.
- Have your septic tank de-sludged every 3–5 years (or as recommended) to prevent clogging.
- Conserve water throughout your home to reduce strain on the system and extend its life.
- Check that household products are suitable for use in septic systems.
- Engage a qualified contractor to regularly inspect and service your system.
- Keep a record of all inspections, servicing and maintenance activities.
Don’t:
- Use large quantities of bleaches, disinfectants, nappy soakers or stain removers – they kill beneficial bacteria.
- Flush foreign materials such as nappies, tampons, condoms or wipes – they cause blockages and costly repairs.
- Use more than the recommended amount of detergents.
- Pour fats, oils or grease down the drain – they clog pipes and trenches.
- Install or use sink macerators (sinkerators) – instead, compost or dispose of food scraps separately.
- Allow children or pets to play on the land application area, as they may be exposed to harmful bacteria.
