Maintaining Your On Site Sewage Facility (OSSF)

An On‑Site Sewage Facility (OSSF) is a system installed on your property to treat household wastewater on‑site. Most systems consist of two main components:

• A treatment unit (such as a septic tank or aerated wastewater treatment system)
• A Land Application Area (LAA), where treated wastewater is applied to soil or grass

Both components must be maintained together for the system to function properly.

Further information on the different types of OSSFs is available at:
https://www.frasercoast.qld.gov.au/Planning-and-Building/Plumbing/On-site-sewage-facilities

Good maintenance helps to:

• Keep wastewater treatment working efficiently
• Reduce the risk of blockages, breakdowns or system failure
• Prevent damage to irrigation and distribution components
• Extend the lifespan of the system
• Avoid unpleasant odours or wet areas in the yard
• Protect the environment
• Ensure ongoing compliance with permit conditions

Simple actions taken regularly can prevent costly repairs later.

Good Practices

• Use water efficiently and spread water use throughout the day (for example, alternating washing machine use)
• Use biodegradable household cleaning products that are low in harsh chemicals
• Keep tank lids, inspection points and vents secure and accessible
• Arrange routine servicing and pump‑outs in accordance with service provider recommendations

Things to Avoid

• Flushing wipes, nappies, paper towels, fats, oils or chemicals and sanitary items into the system
• Discharging large volumes of water into the system over short periods
• Ignoring warning signs such as alarms, odours or soggy ground

For system‑specific limitations, contact your OSSF manufacturer or service provider directly.

The Land Application Area is where treated wastewater is absorbed by soil or grass. Protecting this area is critical to system performance.

The LAA should remain:

• Clearly identifiable
• Free from damage or soil compaction
• Covered with healthy, well‑maintained grass
• Free from stored items or structures

If you are considering building near a Land Application Area (LAA), or if you are unsure of the LAA location or requirements, please contact Fraser Coast Regional Council - Plumbing Services.

Vehicles and heavy loads can compact soil and damage irrigation lines or other system components.

To protect your LAA:

• Do not drive, park or store vehicles, trailers, caravans or machinery on the LAA
•  Keep livestock and penned animals off the area
•  Avoid repeated foot traffic over subsurface irrigation areas

Ride on lawnmowers are acceptable to ensure maintenance.

Soil compaction reduces absorption and may cause wastewater to surface.

Healthy grass assists with absorbing moisture and nutrients.

To maintain grass in the LAA:

• Regularly mow grass
• Avoid scalping or removing grass cover
• Repair bare or eroded patches promptly
• Maintain even coverage across the whole area

Lawns should remain neat, stable and well covered at all times.

The LAA must remain clear and unobstructed to allow even wastewater distribution.

Do not place or store:

• Building or landscaping materials
• Boats, trailers or caravans
• Garden sheds, play equipment or furniture
• Stockpiled soil, mulch, gravel or fill

Stored items can block irrigation, compact soil, reduce evapotranspiration and interfere with system operation.

Subsurface LAA systems distribute treated wastewater below ground through irrigation lines or other piped systems.

To keep these systems operating effectively:

• Do not dig, excavate or landscape over the LAA
• Do not divert wastewater to the surface
• Avoid planting deep‑rooted trees or shrubs
• Monitor for unusually wet areas or odours
• Have irrigation lines serviced or flushed as recommended

Persistent wet areas may indicate damage or blockage.

Surface irrigation systems apply treated wastewater across grass or other approved surface materials.

For effective operation:

• Keep sprinklers free from obstructions
•  Ensure even coverage across the approved area
•  Periodically move or adjust sprinklers where required
•  Maintain grass to prevent pooling or runoff
•  Avoid irrigation during very wet conditions
•  Do not alter the system from its approved design

Surface areas should be dry to the touch once irrigation has finished.

Contact a service provider if you observe:

• Sewage or wastewater odours
• Ponding or persistently wet ground
• Unusually fast grass growth in patches
• Alarms or warning lights activating
• Slow‑draining household fixtures

Early action can prevent further issues and damage.

Ongoing care of your OSSF and Land Application Area supports effective operation, reduces the likelihood of failure and protects public health and the environment.

Protecting the LAA, maintaining grass cover and avoiding damage are some of the most effective actions homeowners can take.